Science.gov

Sample records for active base isolation

  1. Active vibration isolation platform on base of magnetorheological elastomers

    NASA Astrophysics Data System (ADS)

    Mikhailov, Valery P.; Bazinenkov, Alexey M.

    2017-06-01

    The article describes the active vibration isolation platform on base of magnetorheological (MR) elastomers. An active damper based on the MR elastomers can be used as an actuator of micro- or nanopositioning for a vibroinsulated object. The MR elastomers give such advantages for active control of vibration as large range of displacements (up to 1 mm), more efficient absorption of the vibration energy, possibility of active control of amplitude-frequency characteristics and positioning with millisecond response speed and nanometer running accuracy. The article presents the results of experimental studies of the most important active damper parameters. Those are starting current, transient time for stepping, transmission coefficient of the vibration displacement amplitude.

  2. Effect of auditory isolation on activity-based anorexia.

    PubMed

    Fraga, Ángela; De Pedro, Belén; Cerrato, María; Carrera, Olaia; Gutiérrez, Emilio

    2012-01-01

    The objective was to study male and female rats exposed to Activity-Based Anorexia (ABA; simultaneous exposition to food restriction and free access to an activity wheel) under two conditions of sound attenuation, by means of different arrangements of wheels (standard versus isolation) in the laboratory room. Regardless of the sound attenuation condition, all but one male and one female with access to wheels had to be removed from the experiment, but extended ABA endurance was found in rats in the sound attenuation condition. Furthermore, significantly lower levels of running were observed in both males and females under the sound attenuation arrangement in the isolation condition. The results suggest that external stimulation plays a role in the activity displayed by rats exposed to ABA, and that the reduction of external stimulation diminishes running but does not protect rats from developing ABA.

  3. Base isolation: Fresh insight

    SciTech Connect

    Shustov, V.

    1993-07-15

    The objective of the research is a further development of the engineering concept of seismic isolation. Neglecting the transient stage of seismic loading results in a widespread misjudgement: The force of resistance associated with velocity is mostly conceived as a source of damping vibrations, though it is an active force at the same time, during an earthquake type excitation. For very pliant systems such as base isolated structures with relatively low bearing stiffness and with artificially added heavy damping mechanism, the so called `damping`` force may occur even the main pushing force at an earthquake. Thus, one of the two basic pillars of the common seismic isolation philosophy, namely, the doctrine of usefulness and necessity of a strong damping mechanism, is turning out to be a self-deception, sometimes even jeopardizing the safety of structures and discrediting the very idea of seismic isolation. There is a way out: breaking with damping dependancy.

  4. An investigation into active vibration isolation based on predictive control: Part I: Energy source control

    NASA Astrophysics Data System (ADS)

    Fei, H. Z.; Zheng, G. T.; Liu, Z. G.

    2006-09-01

    We report the results of a recent study for the active vibration isolation with whole-spacecraft vibration isolation as an application background into which three parts are divided: (i) energy source control, (ii) nonlinearity and time delay, (iii) implementation and experiment. This paper is the first in this three-part series report, which presents theoretical and experimental investigations into pressure tracking system for energy source control of the isolator. Considering the special environment of the rocket and expected characteristics of actuators, where the isolator will be arranged between the rocket and the spacecraft, pneumatic actuator is proposed to realize the active isolation control. In order to improve the dynamic characteristics of the pneumatic isolator, a cascade control algorithm with double loop structure and predictive control algorithm for pressure tracking control of the inner loop are proposed. In the current paper, a pressure tracking control system using model predictive control (MPC) is studied first. A pneumatic model around pressure work point is built firstly by simplifying the flow equation of valve's orifices and pressure differential equation of the chambers. With this model, an MPC algorithm in the state space is developed, and problems including control parameter choice and command horizon generator are discussed in detail. In addition, by adding model error correction loop and velocity compensation feedback, effects of model uncertainty and volume variation of chambers are reduced greatly. Thus with this design, the real-time pressure tracking can be guaranteed, and so that the active control system can work at higher frequency range.

  5. Biological activities of some Acacia spp. (Fabaceae) against new clinical isolates identified by ribosomal RNA gene-based phylogenetic analysis.

    PubMed

    Mahmoud, Mahmoud Fawzy; Alrumman, Sulaiman Abdullah; Hesham, Abd El-Latif

    2016-01-01

    Nowadays,most of the pathogenic bacteria become resistant to antibiotics. Therefore,the pharmaceutical properties of the natural plant extracts have become of interest to researchers as alternative antimicrobial agents. In this study,antibacterial activities of extract gained from Acacia etbaica, Acacia laeta, Acacia origena and Acacia pycnantha have been evaluated against isolated pathogenic bacteria (Strains MFM-01, MFM-10 and AH-09) using agar well diffusion methods.The bacterial strains were isolated from infected individuals,and their exact identification was detected on the basis of 16S rRNA gene amplification and sequence determination. Alignment results and the comparison of 16 SrRN A gene sequences of the isolates to 16 SrRN A gene sequences available in Gen Bank data base as well as the phylogenetic analysis confirmed the accurate position of the isolates as Klebsiella oxytoca strain MFM-01, Staphylococcus aureus strain MFM-10 and Klebsiella pneumoniae strain AH-09. Except for cold water, all tested solvents (Chloroform, petroleum ether, methanol, diethyl ether, and acetone) showed variation in their activity against studied bacteria. GC-MS analysis of ethanol extracts showed that four investigated Acacia species have different phyto components. Eight important pharmaceutical components were found in the legume of Acacia etbaica, seven in the legume of Acacia laeta, fifteen in the legume of Acacia origena and nine in the leaves of Acacia pycnantha. A dendrogram was constructed based on chemical composition, revealed that Acacia laeta is more closely related to Acacia etbaica forming on eclade, whereas Acacia origena less similar to other species. Our results demonstrated that, investigated plants and chemical compounds present could be used as promising antibacterial agents.

  6. Isolation of an ES-Derived Cardiovascular Multipotent Cell Population Based on VE-Cadherin Promoter Activity

    PubMed Central

    Maltabe, Violetta A.; Barka, Eleonora; Kontonika, Marianthi; Florou, Dimitra; Kouvara-Pritsouli, Maria; Roumpi, Maria; Agathopoulos, Simeon; Kolettis, Theofilos M.

    2016-01-01

    Embryonic Stem (ES) or induced Pluripotent Stem (iPS) cells are important sources for cardiomyocyte generation, targeted for regenerative therapies. Several in vitro protocols are currently utilized for their differentiation, but the value of cell-based approaches remains unclear. Here, we characterized a cardiovascular progenitor population derived during ES differentiation, after selection based on VE-cadherin promoter (Pvec) activity. ESCs were genetically modified with an episomal vector, allowing the expression of puromycin resistance gene, under Pvec activity. Puromycin-surviving cells displayed cardiac and endothelial progenitor cells characteristics. Expansion and self-renewal of this cardiac and endothelial dual-progenitor population (CEDP) were achieved by Wnt/β-catenin pathway activation. CEDPs express early cardiac developmental stage-specific markers but not markers of differentiated cardiomyocytes. Similarly, CEDPs express endothelial markers. However, CEDPs can undergo differentiation predominantly to cTnT+ (~47%) and VE-cadherin+ (~28%) cells. Transplantation of CEDPs in the left heart ventricle of adult rats showed that CEDPs-derived cells survive and differentiate in vivo for at least 14 days after transplantation. A novel, dual-progenitor population was isolated during ESCs differentiation, based on Pvec activity. This lineage can self-renew, permitting its maintenance as a source of cardiovascular progenitor cells and constitutes a useful source for regenerative approaches. PMID:28101109

  7. Model-based fault detection and isolation for intermittently active faults with application to motion-based thruster fault detection and isolation for spacecraft

    NASA Technical Reports Server (NTRS)

    Wilson, Edward (Inventor)

    2008-01-01

    The present invention is a method for detecting and isolating fault modes in a system having a model describing its behavior and regularly sampled measurements. The models are used to calculate past and present deviations from measurements that would result with no faults present, as well as with one or more potential fault modes present. Algorithms that calculate and store these deviations, along with memory of when said faults, if present, would have an effect on the said actual measurements, are used to detect when a fault is present. Related algorithms are used to exonerate false fault modes and finally to isolate the true fault mode. This invention is presented with application to detection and isolation of thruster faults for a thruster-controlled spacecraft. As a supporting aspect of the invention, a novel, effective, and efficient filtering method for estimating the derivative of a noisy signal is presented.

  8. Antimicrobial activities of polyhexamethylene guanidine hydrochloride-based disinfectant against fungi isolated from cocoa beans and reference strains of bacteria.

    PubMed

    Mathurin, Yao K; Koffi-Nevry, Rose; Guéhi, Simplice T; Tano, Kablan; Oulé, Mathias K

    2012-06-01

    This study was conducted to assess the antibacterial and the antifungal activity of a polyhexamethylene guanidine hydrochloride (PHMGH)-based disinfectant and to determine if it could be used as a disinfectant for the treatment of cocoa beans. The activity of PHMGH was tested in vitro for efficacy against five reference strains of pathogenic bacteria and six strains of fungi isolated from cocoa beans. All the strains tested were sensitive to the disinfectant. The MICs reported were between 0.01 and 1.9 mg/ml and equal to the MBC or minimum fungicidal concentration (MFC) regardless of the strains of those microorganisms. The bacteria were more sensitive to PHMGH than were the fungi. Enterobacter cloacae was the most sensitive bacterium with a MIC and MBC of 0.01 mg/ml, whereas the genus Aspergillus was the least susceptible of the microorganisms tested, with a MIC and MFC from 1.0 to 1.9 mg/ml. The time required for the activity of PHMGH varies from 2 min for Enterobacter cloacae to 12 min for Aspergillus tamarii and generally increases with the MBC or the MFC. Through this in vitro study, the PHMGH has been proved to be bactericidal and fungicidal on the strains studied. Hence, it could probably serve as a fungicidal disinfectant for the treatment of cocoa beans after harvesting.

  9. Active Inertial Vibration Isolators And Dampers

    NASA Technical Reports Server (NTRS)

    Laughlin, Darren; Blackburn, John; Smith, Dennis

    1994-01-01

    Report describes development of active inertial vibration isolators and dampers in which actuators electromagnet coils moving linearly within permanent magnetic fields in housings, somewhat as though massive, low-frequency voice coils in loudspeakers. Discusses principle of operation, electrical and mechanical considerations in design of actuators, characteristics of accelerometers, and frequency responses of control systems. Describes design and performance of one- and three-degree-of-freedom vibration-suppressing system based on concept.

  10. Proteasomes: Isolation and Activity Assays

    PubMed Central

    Li, Yanjie; Tomko, Robert J.; Hochstrasser, Mark

    2015-01-01

    In eukaryotes, damaged or unneeded proteins are typically degraded by the ubiquitin-proteasome system. In this system, the protein substrate is often first covalently modified with a chain of ubiquitin polypeptides. This chain serves as a signal for delivery to the 26S proteasome, a 2.5 MDa, ATP-dependent multisubunit protease complex. The proteasome consists of a barrel-shaped 20S core particle (CP) that is capped on one or both of its ends by a 19S regulatory particle (RP). The RP is responsible for recognizing the substrate, unfolding it, and translocating it into the CP for destruction. Here we describe simple, one-step purifications scheme for isolating the 26S proteasome and its 19S RP and 20S CP subcomplexes from the yeast Saccharomyces cerevisiae, as well as assays for measuring ubiquitin-dependent and ubiquitin-independent proteolytic activity in vitro. PMID:26061243

  11. A fluorescence-activated cell sorting-based strategy for rapid isolation of high-lipid Chlamydomonas mutants.

    PubMed

    Terashima, Mia; Freeman, Elizabeth S; Jinkerson, Robert E; Jonikas, Martin C

    2015-01-01

    There is significant interest in farming algae for the direct production of biofuels and valuable lipids. Chlamydomonas reinhardtii is the leading model system for studying lipid metabolism in green algae, but current methods for isolating mutants of this organism with a perturbed lipid content are slow and tedious. Here, we present the Chlamydomonas high-lipid sorting (CHiLiS) strategy, which enables enrichment of high-lipid mutants by fluorescence-activated cell sorting (FACS) of pooled mutants stained with the lipid-sensitive dye Nile Red. This method only takes 5 weeks from mutagenesis to mutant isolation. We developed a staining protocol that allows quantification of lipid content while preserving cell viability. We improved separation of high-lipid mutants from the wild type by using each cell's chlorophyll fluorescence as an internal control. We initially demonstrated 20-fold enrichment of the known high-lipid mutant sta1 from a mixture of sta1 and wild-type cells. We then applied CHiLiS to sort thousands of high-lipid cells from a pool of about 60,000 mutants. Flow cytometry analysis of 24 individual mutants isolated by this approach revealed that about 50% showed a reproducible high-lipid phenotype. We further characterized nine of the mutants with the highest lipid content by flame ionization detection and mass spectrometry lipidomics. All mutants analyzed had a higher triacylglycerol content and perturbed whole-cell fatty acid composition. One arbitrarily chosen mutant was evaluated by microscopy, revealing larger lipid droplets than the wild type. The unprecedented throughput of CHiLiS opens the door to a systems-level understanding of green algal lipid biology by enabling genome-saturating isolation of mutants in key genes.

  12. Electromechanical lever blocks for active vibration isolation

    NASA Astrophysics Data System (ADS)

    Zago, Lorenzo; Genequand, Pierre M.

    2000-04-01

    This paper is a follow-up of a presentation at the Smart Structures Symposium of 1998. There we described an innovative technical solution which provides a combined passive damping and isolation interface with the appropriate transmissibility characteristics between a vibrating base and a sensitive payload, typically an optical terminal/telescope. The particularity of the solution is primarily found in the implementation of energy dissipation by means linear electromagnetic linear motors leveraged by means of flexure elements, to constitute an integrated resistor-damped electromechanic lever block, which we called MEDI (Mechanical Elastic element for Damping and Isolation). Passive viscous damping with attenuation of the order of -20 dB at 50 Hz with respect to a hard fixation, is obtained by simply short- circuiting the electro-magnetic motor. The study and test program presented here extends the application of MEDIs to active vibration reduction systems. The study, contracted by the European Space Agency, aimed at investigating the possibility of using the MEDI as an active isolator for scientific experiments in the International Space Station. By controlling the current in the electromagnetic motor in closed loop with the signal from specially designed force sensor (with extremely low noise), we achieved attenuation of the order of -15 dB at 1 Hz, -30 dB at 10 Hz, -50 dB at 30 Hz, with the isolation slope starting as low as 0.1 Hz.

  13. Entry inhibitor-based microbicides are active in vitro against HIV-1 isolates from multiple genetic subtypes

    SciTech Connect

    Ketas, Thomas J.; Schader, Susan M.; Zurita, Juan; Teo, Esther; Polonis, Victoria; Lu Min; Klasse, Per Johan; Moore, John P. . E-mail: jpm2003@med.cornell.edu

    2007-08-01

    Inhibitors of viral entry are under consideration as topical microbicides to prevent HIV-1 sexual transmission. Small molecules targeting HIV-1 gp120 (BMS-378806) or CCR5 (CMPD167), and a peptide fusion inhibitor (C52L), each blocks vaginal infection of macaques by a SHIV. A microbicide, however, must be active against multiple HIV-1 variants. We therefore tested BMS-C (a BMS-378806 derivative), CMPD167, C52L and the CXCR4 ligand AMD3465, alone and in combination, against 25 primary R5, 12 X4 and 7 R5X4 isolates from subtypes A-G. At high concentrations (0.1-1 {mu}M), the replication of most R5 isolates in human donor lymphocytes was inhibited by > 90%. At lower concentrations, double and triple combinations were more effective than individual inhibitors. Similar results were obtained with X4 viruses when AMD3465 was substituted for CMPD167. The R5X4 viruses were inhibited by combining AMD3465 with CMPD167, or by the coreceptor-independent compounds. Thus, combining entry inhibitors may improve microbicide effectiveness.

  14. Enzymatic activity of fungi isolated from crops

    PubMed Central

    Cholewa, Grażyna; Sobczak, Paweł; Silny, Wojciech; Nadulski, Rafał; Wojtyła-Buciora, Paulina; Zagórski, Jerzy

    2016-01-01

    Aim To detect and assess the activity of extracellular hydrolytic enzymes and to find differences in enzymograms between fungi isolated from wheat and rye samples and grown on Czapek-Dox Broth and Sabouraud Dextrose Broth enriched with cereal (wheat or rye). Isolated strains were also classified in the scale of biosafety levels (BSL). Material and methods The study used 23 strains of fungi cultured from samples of wheat and rye (grain, grain dust obtained during threshing and soil) collected in the Lublin region (eastern Poland). API ZYM test (bioMérieux) was carried out according to the manufacturer’s instructions. Classification of BSL (Biosafety levels) was based on the current literature. Results High enzymatic activity was found in strains cultured in media containing 1% of wheat grain (Bipolaris holmi, Penicillium decumbens) and with an addition of 1% of rye grain (Cladosporium herbarum, Aspergillus versicolor, Alternaria alternata). The total number of enzymes varied depending on the type of media, and in most cases it was higher in the culture where an addition of cereal grains was used. Conclusions Isolated strains of fungi reveal differences in the profiles of the enzyme assay. It can be assumed that the substrate enriched in grains stimulate the higher activity of mold enzymes. PMID:28035224

  15. Multi-axial active isolation for seismic protection of buildings

    NASA Astrophysics Data System (ADS)

    Chang, Chia-Ming

    Structural control technology has been widely accepted as an effective means for the protection of structures against seismic hazards. Passive base isolation is one of the common structural control techniques used to enhance the performance of structures subjected to severe earthquake excitations. Isolation bearings employed at the base of a structure naturally increase its flexibility, but concurrently result in large base displacements. The combination of base isolation with active control, i.e., active base isolation, creates the possibility of achieving a balanced level of control performance, reducing both floor accelerations as well as base displacements. Many theoretical papers have been written by researchers regarding active base isolation, and a few experiments have been performed to verify these theories; however, challenges in appropriately scaling the structural system and modeling the complex nature of control-structure interaction have limited the applicability of these results. Moreover, most experiments only focus on the implementation of active base isolation under unidirectional excitations. Earthquakes are intrinsically multi-dimensional, resulting in out-of-plane responses, including torsional responses. Therefore, an active isolation system for buildings using multi-axial active control devices against multi-directional excitations must be considered. The focus of this dissertation is the development and experimental verification of active isolation strategies for multi-story buildings subjected to bi-directional earthquake loadings. First, a model building is designed to match the characteristics of a representative full-scale structure. The selected isolation bearings feature low friction and high vertical stiffness, providing stable behavior. In the context of the multi-dimensional response control, three, custom-manufactured actuators are employed to mitigate both in-plane and out-of-plane responses. To obtain a high-fidelity model of the

  16. A "Kane's Dynamics" Model for the Active Rack Isolation System

    NASA Technical Reports Server (NTRS)

    Hampton, R. D.; Beech, G. S.; Rao, N. N. S.; Rupert, J. K.; Kim, Y. K.

    2001-01-01

    Many microgravity space science experiments require vibratory acceleration levels unachievable without active isolation. The Boeing Corporation's Active Rack Isolation System (ARIS) employs a novel combination of magnetic actuation and mechanical linkages to address these isolation requirements on the International Space Station (ISS). ARIS provides isolation at the rack (International Standard Payload Rack (ISPR)) level. Effective model-based vibration isolation requires: (1) an appropriate isolation device, (2) an adequate dynamic (i.e., mathematical) model of that isolator, and (3) a suitable, corresponding controller. ARIS provides the ISS response to the first requirement. This paper presents one response to the second, in a state space framework intended to facilitate an optimal-controls approach to the third. The authors use "Kane's Dynamics" to develop a state-space, analytical (algebraic) set of linearized equations of motion for ARIS.

  17. A "Kanes's Dynamics" Model for the Active Rack Isolation System

    NASA Technical Reports Server (NTRS)

    Hampton, R. David; Beech, Geoffrey

    1999-01-01

    Many microgravity space-science experiments require vibratory acceleration levels unachievable without active isolation. The Boeing Corporation's Active Rack Isolation System (ARIS) employs a novel combination of magnetic actuation and mechanical linkages, to address these isolation requirements on the International Space Station (ISS). ARIS provides isolation at the rack (international Standard Payload Rack, or ISPR) level. Effective model-based vibration isolation requires (1) an appropriate isolation device, (2) an adequate dynamic (i.e., mathematical) model of that isolator, and (3) a suitable, corresponding controller. ARIS provides the ISS response to the first requirement. This paper presents one response to the second, in a state-space framework intended to facilitate an optimal-controls approach to the third. The authors use "Kane's Dynamics" to develop an state-space, analytical (algebraic) set of linearized equations of motion for ARIS.

  18. Effects of isolation on various lymphocyte activities

    SciTech Connect

    Jessop, J.J.

    1986-01-01

    Prolonged exposure of Sprague Dawley male rats to isolation, water scheduling, or their combination resulted in an enhanced lymphocyte proliferative response to mitogen. Time course studies of effects of isolation on mitogenic response of splenic and/or blood T and B lymphocytes and splenic NK cell activity demonstrated a suppression with short term exposure followed by an enhancement with prolonged exposure. Use of immunoperoxidase staining techniques to identify splenic T or T helper cells revealed that prolonged exposure to isolation had no significant effect on the proportion of these cell populations in the spleen. Examination of the data by Lineweaver-Burke plot and plot of the data as % maximum response showed that prolonged exposure to isolation did not alter the sensitivity of the lymphocytes to mitogen. Involvement of corticosteroids and opioid peptides in mediation of the effects of exposure to isolation on lymphocyte activity was assessed by measurement of plasma corticosterone by radioimmunoassay and by examination of the ability of the opioid antagonist naltrexone to alter the effects of isolation on lymphocyte proliferative response to mitogen. Attempts were made to mimic the effects of short-term isolation on lymphocyte activity by morphine sulfate administration.

  19. Isolated polypeptide having arabinofuranosidase activity

    DOEpatents

    Foreman, Pamela; Van Solingen, Pieter; Goedegebuur, Frits; Ward, Michael

    2010-02-23

    Described herein are novel gene sequences isolated from Trichoderma reesei. Two genes encoding proteins comprising a cellulose binding domain, one encoding an arabionfuranosidase and one encoding an acetylxylanesterase are described. The sequences, CIP1 and CIP2, contain a cellulose binding domain. These proteins are especially useful in the textile and detergent industry and in pulp and paper industry. TABLE-US-00001 cip1 cDNA sequence (SEQ ID NO: 1) GACTAGTTCA TAATACAGTA GTTGAGTTCA TAGCAACTTC 50 ACTCTCTAGC TGAACAAATT ATCTGCGCAA ACATGGTTCG CCGGACTGCT 100 CTGCTGGCCC TTGGGGCTCT CTCAACGCTC TCTATGGCCC AAATCTCAGA 150 CGACTTCGAG TCGGGCTGGG ATCAGACTAA ATGGCCCATT TCGGCACCAG 200 ACTGTAACCA GGGCGGCACC GTCAGCCTCG ACACCACAGT AGCCCACAGC 250 GGCAGCAACT CCATGAAGGT CGTTGGTGGC CCCAATGGCT ACTGTGGACA 300 CATCTTCTTC GGCACTACCC AGGTGCCAAC TGGGGATGTA TATGTCAGAG 350 CTTGGATTCG GCTTCAGACT GCTCTCGGCA GCAACCACGT CACATTCATC 400 ATCATGCCAG ACACCGCTCA GGGAGGGAAG CACCTCCGAA TTGGTGGCCA 450 AAGCCAAGTT CTCGACTACA ACCGCGAGTC CGACGATGCC ACTCTTCCGG 500 ACCTGTCTCC CAACGGCATT GCCTCCACCG TCACTCTGCC TACCGGCGCG 550 TTCCAGTGCT TCGAGTACCA CCTGGGCACT GACGGAACCA TCGAGACGTG 600 GCTCAACGGC AGCCTCATCC CGGGCATGAC CGTGGGCCCT GGCGTCGACA 650 ATCCAAACGA CGCTGGCTGG ACGAGGGCCA GCTATATTCC GGAGATCACC 700 GGTGTCAACT TTGGCTGGGA GGCCTACAGC GGAGACGTCA ACACCGTCTG 750 GTTCGACGAC ATCTCGATTG CGTCGACCCG CGTGGGATGC GGCCCCGGCA 800 GCCCCGGCGG TCCTGGAAGC TCGACGACTG GGCGTAGCAG CACCTCGGGC 850 CCGACGAGCA CTTCGAGGCC AAGCACCACC ATTCCGCCAC CGACTTCCAG 900 GACAACGACC GCCACGGGTC CGACTCAGAC ACACTATGGC CAGTGCGGAG 1000 GGATTGGTTA CAGCGGGCCT ACGGTCTGCG CGAGCGGCAC GACCTGCCAG 1050 GTCCTGAACC CATACTACTC CCAGTGCTTA TAAGGGGATG AGCATGGAGT 1100 GAAGTGAAGT GAAGTGGAGA GAGTTGAAGT GGCATTGCGC TCGGCTGGGT 1150 AGATAAAAGT CAGCAGCTAT GAATACTCTA TGTGATGCTC ATTGGCGTGT 1200 ACGTTTTAAA AAAAAAAAAA AAAAAAAAAA AAAAAAAAAA AAAAAAAAAA 1250 AAAAAAAAAA AAAAAAAAAG GGGGCGGCCG C 1271

  20. Silicon photonics broadband modulation-based isolator.

    PubMed

    Doerr, C R; Chen, L; Vermeulen, D

    2014-02-24

    We discuss an optical isolator design based on tandem phase modulators in a long interferometer. It provides low-loss, broadband isolation in a photonic integrated circuit without requiring special materials or fabrication steps. It was demonstrated in silicon photonics.

  1. Active thermal isolation for temperature responsive sensors

    NASA Technical Reports Server (NTRS)

    Martinson, Scott D. (Inventor); Gray, David L. (Inventor); Carraway, Debra L. (Inventor); Reda, Daniel C. (Inventor)

    1994-01-01

    A temperature responsive sensor is located in the airflow over the specified surface of a body and is maintained at a constant temperature. An active thermal isolator is located between this temperature responsive sensor and the specified surface of the body. The temperature of this isolator is controlled to reduce conductive heat flow from the temperature responsive sensor to the body. This temperature control includes: (1) operating the isolator at the same temperature as the constant temperature of the sensor and (2) establishing a fixed boundary temperature which is either less than or equal to or slightly greater than the sensor constant temperature.

  2. Active thermal isolation for temperature responsive sensors

    NASA Technical Reports Server (NTRS)

    Martinson, Scott D. (Inventor); Gray, David L. (Inventor); Carraway, Debra L. (Inventor); Reda, Daniel C. (Inventor)

    1994-01-01

    The detection of flow transition between laminar and turbulent flow and of shear stress or skin friction of airfoils is important in basic research for validation of airfoil theory and design. These values are conventionally measured using hot film nickel sensors deposited on a polyimide substrate. The substrate electrically insulates the sensor and underlying airfoil but is prevented from thermally isolating the sensor by thickness constraints necessary to avoid flow contamination. Proposed heating of the model surface is difficult to control, requires significant energy expenditures, and may alter the basic flow state of the airfoil. A temperature responsive sensor is located in the airflow over the specified surface of a body and is maintained at a constant temperature. An active thermal isolator is located between this temperature responsive sensor and the specific surface of the body. The total thickness of the isolator and sensor avoid any contamination of the flow. The temperature of this isolator is controlled to reduce conductive heat flow from the temperature responsive sensor to the body. This temperature control includes (1) operating the isolator at the same temperature as the constant temperature of the sensor; and (2) establishing a fixed boundary temperature which is either less than or equal to, or slightly greater than the sensor constant temperature. The present invention accordingly thermally isolates a temperature responsive sensor in an energy efficient, controllable manner while avoiding any contamination of the flow.

  3. Saponins from Panax bipinnatifidus Seem.: New strategy of extraction, isolation, and evaluation of tyrosinase inhibitory activity based on mathematical calculations.

    PubMed

    Zhang, Yuchi; Shi, Chong; Liu, Chunming; Yu, Min; Qi, Yanjuan; Li, Sainan

    2016-12-15

    A hyphenated accelerated solvent extraction (ASE) technique coupled with centrifugal partition chromatography (CPC), ultra high performance liquid chromatography (UPLC), and mass spectrometry (MS) was established. The CPC fractions were prepared using the hyphenated technique. Subsequently, tyrosinase inhibitory activities of the CPC fractions were experimentally evaluated, and the activities of individual components were calculated theoretically. This new approach was applied to saponin fractions obtained from 10.0g of raw Panax bipinnatifidus Seem. via a biphasic solvent system of ethyl acetate/n-butanol/methanol/water (2:3:2:5, v/v/v/v). The CPC fractions monitoring was performed using an online UPLC/PDA system at 5-min intervals. The tyrosinase inhibitory activities of all fractions were analysed using the fluorescence method. Mathematical calculations indicated that the inhibition rates of the ginsenosides Rh1, Rh2, Rg1, Rg2, and chikusetsusaponin L5 were all above 50.00%, showing potential for further development. The results were confirmed by comparison with authentic standards.

  4. Fractional order PID control design for semi-active control of smart base-isolated structures: A multi-objective cuckoo search approach.

    PubMed

    Zamani, Abbas-Ali; Tavakoli, Saeed; Etedali, Sadegh

    2017-03-01

    Fractional order PID (FOPID) controllers are introduced as a general form of classical PID controllers using fractional calculus. As this controller provides good disturbance rejection and is robust against plant uncertainties it is appropriate for the vibration mitigation in structures. In this paper, an FOPID controller is designed to adjust the contact force of piezoelectric friction dampers for semi-active control of base-isolated structures during far-field and near-field earthquake excitations. A multi-objective cuckoo search algorithm is employed to tune the controller parameters. Considering the resulting Pareto optimal front, the best input for the FOPID controller is selected. For seven pairs of earthquakes and nine performance indices, the performance of the proposed controller is compared with those provided by several well-known control techniques. According to the simulation results, the proposed controller performs better than other controllers in terms of simultaneous reduction of the maximum base displacement and story acceleration for various types of earthquakes. Also, it provides acceptable responses in terms of inter-story drifts, root mean square of base displacements and floor acceleration. In addition, the evaluation of robustness for a stiffness uncertainty of ±10% indicates that the proposed controller gives a robust performance against such modeling errors.

  5. Isolation, Co-Crystallization and Structure-Based Characterization of Anabaenopeptins as Highly Potent Inhibitors of Activated Thrombin Activatable Fibrinolysis Inhibitor (TAFIa)

    PubMed Central

    Schreuder, Herman; Liesum, Alexander; Lönze, Petra; Stump, Heike; Hoffmann, Holger; Schiell, Matthias; Kurz, Michael; Toti, Luigi; Bauer, Armin; Kallus, Christopher; Klemke-Jahn, Christine; Czech, Jörg; Kramer, Dan; Enke, Heike; Niedermeyer, Timo H. J.; Morrison, Vincent; Kumar, Vasant; Brönstrup, Mark

    2016-01-01

    Mature thrombin activatable fibrinolysis inhibitor (TAFIa) is a carboxypeptidase that stabilizes fibrin clots by removing C-terminal arginines and lysines from partially degraded fibrin. Inhibition of TAFIa stimulates the degradation of fibrin clots and may help to prevent thrombosis. Applying a lead finding approach based on literature-mining, we discovered that anabaenopeptins, cyclic peptides produced by cyanobacteria, were potent inhibitors of TAFIa with IC50 values as low as 1.5 nM. We describe the isolation and structure elucidation of 20 anabaenopeptins, including 13 novel congeners, as well as their pronounced structure-activity relationships (SAR) with respect to inhibition of TAFIa. Crystal structures of the anabaenopeptins B, C and F bound to the surrogate protease carboxypeptidase B revealed the binding modes of these large (~850 Da) compounds in detail and explained the observed SAR, i.e. the strong dependence of the potency on a basic (Arg, Lys) exocyclic residue that addressed the S1’ binding pocket, and a broad tolerance towards substitutions in the pentacyclic ring that acted as a plug of the active site. PMID:27604544

  6. Extracellular enzymatic activity of Microsporum canis isolates.

    PubMed

    Papini, R; Mancianti, F

    The enzymatic activity of 70 feline and canine Microsporum canis isolates was determined by the Api-Zym test. The liquid phase of cultures, inoculated into Tryptic Soy Broth, was used to examine 19 enzymes. Considerable differences were observed among the extracellular enzymatic patterns. All the isolates produced alkaline phosphatase and beta-glucosidase, while lipase (C14), trypsin, chymotrypsin, beta-glucuronidase, and alpha-fucosidase activity was never revealed. Esterase (C4) activity was present in 57 samples (81%), esterase lipase (C8) in 31 (44%), leucine arylamidase in 35 (50%), valine arylamidase and cystine arylamidase in 7 (10%), acid phosphatase in 64 (91%), naphthol-AS-BI-phosphohydrolase in 60 (86%), alpha-galactosidase in 5 (7%), beta-galactosidase in 6 (8%), alpha-glucosidase in 25 (36%), N-acetyl-beta-glucosaminidase in 41 (58%), and alpha-mannosidase in 51 (73%). The beta-galactosidase activity of M. canis has not been reported previously. Remarkable variations of intensity for each enzymatic activity were also detected. It is believed that these results could provide basic data for further investigations on the pathogenic role of enzymes secreted by M. canis.

  7. High-performance passive viscous isolator element for active/passive (hybrid) isolation

    NASA Astrophysics Data System (ADS)

    Davis, Torey; Davis, L. Porter; Sullivan, Jeanne M.; Hoffman, Terry; Das, Alok

    1996-05-01

    A high performance passive isolator has been developed for a multiaxis isolation system for vibration isolation of an optical payload. This passive isolator will be used along with an active element to provide improved vibration isolation performance over previous isolators. The isolator has been designed using ideas developed previously for 'tuned' three parameter passive isolators. The isolator has also been developed offering the lowest system passive break frequencies structurally feasible for the lightweight optical payload. The implementations of these passive isolator design considerations complement the active portion of the system, and also provide the best passive isolation at the higher frequencies long after the active system has 'rolled off.' The mathematics used to design the isolator as well as the isolator's physical attributes are discussed. The unique design challenges of incorporating the passive element with the active, forming one 'hybrid' D-strut$TM, also are discussed. Finally, actual test data from isolator testing are compared to predicted performance, verifying the isolator's exceptional performance and predictability.

  8. Experiments on active precision isolation with a smart conical adapter

    NASA Astrophysics Data System (ADS)

    Li, H.; Li, H. Y.; Chen, Z. B.; Tzou, H. S.

    2016-07-01

    Based on a conical shell adaptor, an active vibration isolator for vibration control of precision payload is designed and tested in this study. Flexible piezoelectric sensors and actuators are bonded on the adaptor surface for active vibration monitoring and control. The mathematical model of a piezoelectric laminated conical shell is derived and then optimal design of the actuators is performed for the first axial vibration mode of the isolation system. A scaled conical adaptor is manufactured with four MFC actuators laminating on its outer surface. Active vibration isolation efficiency is then evaluated on a vibration shaker. The control model is built in Matlab/Simulink and programmed into the dSPACE control board. Experimental results show that, the proposed active isolator is effective in vibration suppression of payloads with the negative velocity feedback control. In contrast, the amplitude responses increase with positive feedback control. Furthermore, the amplitude responses increases when time delay is added into the control signals, and gets the maximum when the delay is close to one quarter of one cycle time.

  9. Broadband optical isolator based on helical metamaterials.

    PubMed

    Cao, Hu; Yang, ZhenYu; Zhao, Ming; Wu, Lin; Zhang, Peng

    2015-05-01

    Based on helical metamaterials, a new broadband optical isolator with a triple-helix structure is proposed in this paper. The right-handed circularly polarized light can transmit through the isolator with its polarization unchanged. The reverse propagating light, which is caused by the reflection of the latter optical devices, is converted into left-handed circularly polarized light that is suppressed by the proposed isolator because of absorption. Our design has some unprecedented advantages such as broad frequency ranges and a compact structure; moreover, neither polarizers nor adscititious magnetic fields are required. Properties of the isolator are investigated using the finite-difference time-domain method, and this phenomenon is studied by the mechanism of helical antenna theory.

  10. Active vibration isolation through a Stewart platform with piezoelectric actuators

    NASA Astrophysics Data System (ADS)

    Wang, Chaoxin; Xie, Xiling; Chen, Yanhao; Zhang, Zhiyi

    2016-09-01

    A Stewart platform with piezoelectric actuators is presented for micro-vibration isolation. The Jacobian matrix of the Stewart platform, which reveals the relationship between the position/pointing of the payload and the extensions of the struts, is derived by the kinematic analysis and modified according to measured FRFs(frequency response function). The dynamic model of the Stewart platform is established by the FRF synthesis method to accommodate flexible modes of the platform. In active isolation, the LMS-based adaptive method is adopted and combined with the Jacobian matrix to suppress pure vibrations of the payload. Numerical simulations and experiments were conducted to prove vibration isolation performance of the Stewart platform subjected to periodical disturbances, and the results have demonstrated that considerable attenuations can be achieved.

  11. Active vibration isolation using smart structures

    NASA Technical Reports Server (NTRS)

    Guigou, C.; Wagstaff, P. R.; Fuller, C. R.

    1991-01-01

    Passive technologies for the isolation of structures from vibrating sources are often inadequate. Using active control inputs applied directly to the source or designing a structure integrating the transducers required for the control inputs and the response measurements are ways of dealing with the problem. Results are given which were obtained on an experimental set up simulating this kind of problem where the form and the position of the transducers could be varied. By measuring the response of the structure integrated over a particular area the effects of particular types of modes could be taken into account to deal with specific types of input or limit particular modes of response more efficiently. Results of using different modes of vibration excitation of the receiving structure with and without control are presented for particular input frequencies. The problems of optimizing the control system to deal with multiple frequency inputs are discussed.

  12. A Survey of Active Vibration Isolation Systems for Microgravity Applications

    NASA Technical Reports Server (NTRS)

    Grodsinsky, Carlos M.; Whorton, Mark S.

    2000-01-01

    In view of the utility of space vehicles as orbiting science laboratories, the need for vibration isolation systems for acceleration sensitive experiments has gained increasing visibility. To date, three active microgravity vibration isolation systems have successfully been demonstrated in flight. This paper provides a tutorial discussion of the microgravity vibration isolation problem including a description of the acceleration environment of the International Space Station and attenuation requirements as well as a comparison of the dynamics of passive isolation, active rack-level isolation, and active payload-level isolation. This paper also surveys the flight test results of the three demonstrated systems: Suppression of Transient Accelerations By Levitation (STABLE); the Microgravity Vibration Isolation Mount (MIM); and the Active Rack Isolation System (ARIS).

  13. Survey of Active Vibration Isolation Systems for Microgravity Applications

    NASA Technical Reports Server (NTRS)

    Grodsinsky, Carlos M.; Whorton, Mark S.

    2000-01-01

    In view of the utility of space vehicles as orbiting science laboratories, the need for vibration isolation systems for acceleration-sensitive experiments has gained increasing visibility. To date, three active microgravity vibration isolation systems have successfully been demonstrated in flight. A tutorial discussion of the microgravity vibration isolation problem, including a description of the acceleration environment of the International Space Station and attenuation requirements, as well as a comparison or the dynamics of passive isolation, active rack-level isolation, and active payload-level isolation is provided. The flight test results of the three demonstrated systems: suppression of transient accelerations by levitation, the microgravity vibration isolation mount, and the active rack isolation system are surveyed.

  14. [Isolation and antimicrobial activities of actinomycetes from vermicompost].

    PubMed

    Wang, Xue-jun; Yan, Shuang-lin; Min, Chang-li; Yang, Yan

    2015-02-01

    In this paper, actinomycetes were isolated from vermicompost by tablet coating method. Antimicrobial activities of actinomycetes were measured by the agar block method. Strains with high activity were identified based on morphology and biochemical characteristics, as well as 16S rDNA gene sequence analysis. The results showed that 26 strains of actinomycetes were isolated, 16 of them had antimicrobial activities to the test strains which accounts for 61.54% of all strains. Among the 16 strains, the strain QYF12 and QYF22 had higher antimicrobial activity to Micrococcus luteus, with a formed inhibition zone of 27 mm and 31 mm, respectively. While the strain QYF26 had higher antimicrobial activity to Bacillus subtilis, and the inhibition zone diameter was 21 mm. Based on the identification of strains with high activity, the strain QYF12 was identified as Streptomyces chartreusis, the strain QYF22 was S. ossamyceticus and the strain QYF26 was S. gancidicus. This study provided a theoretical basis for further separate antibacterial product used for biological control.

  15. Active shape models incorporating isolated landmarks for medical image annotation

    NASA Astrophysics Data System (ADS)

    Norajitra, Tobias; Meinzer, Hans-Peter; Stieltjes, Bram; Maier-Hein, Klaus H.

    2014-03-01

    Apart from their robustness in anatomic surface segmentation, purely surface based 3D Active Shape Models lack the ability to automatically detect and annotate non-surface key points of interest. However, annotation of anatomic landmarks is desirable, as it yields additional anatomic and functional information. Moreover, landmark detection might help to further improve accuracy during ASM segmentation. We present an extension of surface-based 3D Active Shape Models incorporating isolated non-surface landmarks. Positions of isolated and surface landmarks are modeled conjoint within a point distribution model (PDM). Isolated landmark appearance is described by a set of haar-like features, supporting local landmark detection on the PDM estimates using a kNN-Classi er. Landmark detection was evaluated in a leave-one-out cross validation on a reference dataset comprising 45 CT volumes of the human liver after shape space projection. Depending on the anatomical landmark to be detected, our experiments have shown in about 1/4 up to more than 1/2 of all test cases a signi cant improvement in detection accuracy compared to the position estimates delivered by the PDM. Our results encourage further research with regard to the combination of shape priors and machine learning for landmark detection within the Active Shape Model Framework.

  16. Characterization of newly isolated lytic bacteriophages active against Acinetobacter baumannii.

    PubMed

    Merabishvili, Maia; Vandenheuvel, Dieter; Kropinski, Andrew M; Mast, Jan; De Vos, Daniel; Verbeken, Gilbert; Noben, Jean-Paul; Lavigne, Rob; Vaneechoutte, Mario; Pirnay, Jean-Paul

    2014-01-01

    Based on genotyping and host range, two newly isolated lytic bacteriophages, myovirus vB_AbaM_Acibel004 and podovirus vB_AbaP_Acibel007, active against Acinetobacter baumannii clinical strains, were selected from a new phage library for further characterization. The complete genomes of the two phages were analyzed. Both phages are characterized by broad host range and essential features of potential therapeutic phages, such as short latent period (27 and 21 min, respectively), high burst size (125 and 145, respectively), stability of activity in liquid culture and low frequency of occurrence of phage-resistant mutant bacterial cells. Genomic analysis showed that while Acibel004 represents a novel bacteriophage with resemblance to some unclassified Pseudomonas aeruginosa phages, Acibel007 belongs to the well-characterized genus of the Phikmvlikevirus. The newly isolated phages can serve as potential candidates for phage cocktails to control A. baumannii infections.

  17. Antimicrobial Activity of Chlorhexidine, Peracetic acid/ Peroxide hydrogen and Alcohol based compound on Isolated Bacteria in Madani Heart Hospital, Tabriz, Azerbaijan, Iran

    PubMed Central

    Ghotaslou, Reza; Bahrami, Nashmil

    2012-01-01

    Purpose: The aim of present study was to investigate the effect of chemical agents on the clinical isolates in Madani Heart Hospital, Tabriz, Iran. Methods: The minimum bactericide concentration (MBC) of disinfectants including chlorhexidine (Fort), peracetic acid (Micro) and an alcohol based compound (Deconex) on selected bacteria at various dilutions were determined by the standard suspension technique. Results: MBC of Micro, Fort and Deconex were 2-128 mg/L, 2-64 mg/L and 4 - 32 mg/L, respectively. The Gram negative bacteria were more resistance to disinfectant relation to Gram positive bacteria. Conclusion: The results showed that these agents are able to eradicate the bacteria and they can be used lonely. PMID:24312771

  18. Frequency response characteristics and response spectra of base-isolated and un-isolated structures

    SciTech Connect

    Mok, G.C.; Namba, H.

    1995-07-06

    The transmissibility of seismic loads through a linear base-isolation system is analyzed using an impedance method. The results show that the system acts like a {open_quotes}low-pass{close_quotes} filter. It attenuates high-frequency loads but passes through low-frequency ones. The filtering effect depends on the vibration frequencies and damping of the isolated structure and the isolation system. This paper demonstrates the benefits and design principles of base isolation by comparing the transmissibilities and response spectra of isolated and un-isolated structures. Parameters of typical isolated buildings and ground motions of the 1994 Northridge earthquake are used for the demonstration.

  19. Halotolerant Ability and α-Amylase Activity of Some Saltwater Fungal Isolates

    PubMed Central

    Niknejad, Farhad; Moshfegh, Mahsa; Najafzadeh, Mohammad Javad; Houbraken, Jos; Rezaei, Shahla; Zarrini, Gholamreza; Faramarzi, Mohammad Ali; Nafissi-Varcheh, Nastaran

    2013-01-01

    Four halotolerant fungal isolates originating from the saltwater Lake Urmia in Iran were selected during a screening program for salt resistance and α-amylase activity. The isolates were identified based on sequencing the ITS region and a part of the β-tubulin gene, as Penicillium chrysogenum (isolate U1; CBS 132820), Fusarium incarnatum (isolate U2; CBS 132821), and Penicillium polonicum (isolate U3; CBS 132822, and isolate U4; CBS 132823). The growth of these isolates was determined by measuring the colony diameter and mycelia dry weight in Sabouraud dextrose agar and yeast nitrogen base medium supplemented with NaCl, KCl, and LiCl. Isolate U4 showed a growth up in 15% NaCl and U1 was the only isolate that could grow in 20% KCl. None of the strains grew in a media containing LiCl. The salt supplemented medium did not increase the size of colony diameter in all isolates (p > 0.05). The ability of the selected isolates for amylase production was quantitatively tested and showed that P. polonicum isolate U4 was the most potent producer of amylase with a yield of 260.9 U/L after 60 h, whereas P. polonicum isolate U3 was the lowest one with a production level of 97.9 U/L after 48 h. P. polonicum isolate U4 could be a suitable candidate for production of amylase on an industrial scale after optimization. PMID:24250679

  20. Isolating rule- versus evidence-based prefrontal activity during episodic and lexical discrimination: a functional magnetic resonance imaging investigation of detection theory distinctions.

    PubMed

    Dobbins, Ian G; Han, Sanghoon

    2006-11-01

    Dorsolateral and frontopolar prefrontal cortices (PFCs) are often implicated in neuroimaging studies of memory retrieval, with this activity ascribed to controlled monitoring processes indicative of difficult or demanding retrieval. Difficulty, however, is multiply determined, with success rates governed both by the available evidence and by the nature of decision rules applied to that evidence. Using event-related functional magnetic resonance imaging, we isolated these factors by 1) contrasting different decision rules across matched evidence and 2) manipulating the level of evidence within a fixed decision rule. For identically constructed retrieval probes (1 old and 1 new item), same-different (are these different?) compared with forced-choice (which one is old?) decision rules yielded bilateral dorsolateral and right frontopolar PFC increases. However, these regions were unaffected when the available evidence was greatly lowered within forced-choice decisions. Thus, the regions were simultaneously sensitive to the type of decision rule and yet insensitive to the level of evidence supporting those decisions. Analogous lexical tasks yielded similar patterns, demonstrating that the PFC responses were not episodic memory specific. We discuss the mechanistic differences between same-different versus forced-choice decisions and the implications of these data for current theories of PFC activity during episodic remembering and executive control.

  1. Phospholipase and proteinase activities of Candida isolates from denture wearers.

    PubMed

    Marcos-Arias, Cristina; Eraso, Elena; Madariaga, Lucila; Aguirre, Jose Manuel; Quindós, Guillermo

    2011-07-01

    The aim of the present study was to characterise phospholipase and proteinase activities of oral Candida isolates from 100 denture wearers and to study the relationship of these activities with denture stomatitis. Of 100 patients studied, 44 suffered from denture stomatitis. Specimens were collected by swabbing the denture and underlying mucosa. Isolates were previously identified by conventional mycological and genotypic methods. The phospholipase and proteinase activities were evaluated by agar plate methods. A total of 152 isolates were recovered from denture and underlying mucosa, including 101 Candida albicans, 18 Candida tropicalis, 14 Candida glabrata, 11 Candida guilliermondii, four Candida parapsilosis, two Saccharomyces cerevisiae and one isolate each of Candida dubliniensis and Candida krusei. Most C. albicans (97%) showed phospholipase activity; furthermore, the unique C. dubliniensis isolate showed a moderate phospholipase activity. The isolation of C. albicans (chi-square test, P = 0.0016) and phospholipase production by Candida spp. (chi-square test, P = 0.0213) was found to be significantly associated with denture stomatitis. Proteinase production was observed in <30% of isolates, and it was not related to the presence of denture stomatitis (P = 0.7675). Candida albicans isolates may produce both virulence factors, although the proteinase production was only observed in <30% of the isolates. Phospholipase production was exclusive of C. albicans and C. dubliniensis.

  2. [Human social activity under conditions of relative social isolation].

    PubMed

    Prokhvatilov, A Iu

    1992-01-01

    The differences in using a "social isolation" concept in the psychological literature are presented. The term of "relative social isolation" is clarified. A relationship between human adaptation to the relative social isolation environments and the development of his social qualities and social activities is presented. The "social context", dictating motivation attitudes of a man to the isolation situation, emotional experiences, self-appraisal of activity is of crucial importance for evaluating the real environments of relative social isolations. Social activity of a personality is studied as the relations of a man with the conditions of his activity. The results of studying the dynamics of the psychic state of a man during individual and group isolation are compared. It is concluded that social activity of man and his functional state are interrelated. The particular manifestations and direction of the changes in the social activity of the subject depend on the duration of isolation and are determined first of all by social significance and meaningful and balanced work for a person as well as by the amount and frequency of direct and mediated social contacts under specific conditions of relative social isolation.

  3. Mechanical characterization of seismic base isolation elastomers

    SciTech Connect

    Kulak, R.F.; Hughes, T.H.

    1991-01-01

    From the various devices proposed for seismic isolators, the laminated elastomer bearing is emerging as the preferred device for large buildings/structures, such as nuclear reactor plants. The laminated bearing is constructed from alternating thin layers of elastomer and metallic plates (shims). The elastomer is usually a carbon filled natural rubber that exhibits damping when subjected to shear. Recently, some blends of natural and synthetic rubbers have appeared. Before candidate elastomers can be used in seismic isolation bearings, their response to design-basis loads and beyond- design-basis loads must be determined. This entails the development of constitutive models and and then the determination of associated material parameters through specimen testing. This paper describes the methods used to obtain data for characterizing the mechanical response of elastomers used for seismic isolation. The data provides a data base for use in determining material parameters associated with nonlinear constitutive models. In addition, the paper presents a definition for a damping ratio that does not exhibit the usual reduction at higher strain cycles. 2 refs., 6 figs., 1 tab.

  4. Strategy for Isolation of Gene Activation Factors

    DTIC Science & Technology

    1988-11-01

    4723-4733). 10. Singh H, LeBowitz JH, Baldwin AS, Sharp PA: Molecular cloning of an enhancer binding protein: Isolation by screening of an...expression library with a recognition site DNA. Cell, 52:415-423, 1988. 14 ii. Maniatis T, Fritsch EF, Sambrook J: Molecular cloning . A laboratory manual, Cold

  5. Microgravity Active Vibration Isolation System on Parabolic Flights

    NASA Astrophysics Data System (ADS)

    Dong, Wenbo; Pletser, Vladimir; Yang, Yang

    2016-07-01

    The Microgravity Active Vibration Isolation System (MAIS) aims at reducing on-orbit vibrations, providing a better controlled lower gravity environment for microgravity physical science experiments. The MAIS will be launched on Tianzhou-1, the first cargo ship of the China Manned Space Program. The principle of the MAIS is to suspend with electro-magnetic actuators a scientific payload, isolating it from the vibrating stator. The MAIS's vibration isolation capability is frequency-dependent and a decrease of vibration of about 40dB can be attained. The MAIS can accommodate 20kg of scientific payload or sample unit, and provide 30W of power and 1Mbps of data transmission. The MAIS is developed to support microgravity scientific experiments on manned platforms in low earth orbit, in order to meet the scientific requirements for fluid physics, materials science, and fundamental physics investigations, which usually need a very quiet environment, increasing their chances of success and their scientific outcomes. The results of scientific experiments and technology tests obtained with the MAIS will be used to improve future space based research. As the suspension force acting on the payload is very small, the MAIS can only be operative and tested in a weightless environment. The 'Deutsches Zentrum für Luft- und Raumfahrt e.V.' (DLR, German Aerospace Centre) granted a flight opportunity to the MAIS experiment to be tested during its 27th parabolic flight campaign of September 2015 performed on the A310 ZERO-G aircraft managed by the French company Novespace, a subsidiary of the 'Centre National d'Etudes Spatiales' (CNES, French Space Agency). The experiment results confirmed that the 6 degrees of freedom motion control technique was effective, and that the vibration isolation performance fulfilled perfectly the expectations based on theoretical analyses and simulations. This paper will present the design of the MAIS and the experiment results obtained during the

  6. Bacterial isolates from the bryozoan Membranipora membranacea: influence of culture media on isolation and antimicrobial activity.

    PubMed

    Heindl, Herwig; Thiel, Vera; Wiese, Jutta; Imhoff, Johannes F

    2012-03-01

    From specimens of the bryozoan Membranipora membranacea collected in the Baltic Sea, bacteria were isolated on four different media, which significantly increased the diversity of the isolated groups. All isolates were classified according to 16S rRNA gene sequence analysis and tested for antimicrobial properties using a panel of five indicator strains and six different media. Each medium featured a unique set of isolated phylotypes, and a phylogenetically diverse collection of isolates was obtained. A total of 96 isolates were assigned to 49 phylotypes and 29 genera. Only one-third of the members of these genera had been isolated previously from comparable sources. The isolates were affiliated with Alpha- and Gammaproteobacteria, Bacilli, and Actinobacteria. A comparable large portion of up to 22 isolates, i.e., 15 phylotypes, probably represent new species. Likewise, 47 isolates (approximately 50%) displayed antibiotic activities, mostly against grampositive indicator strains. Of the active strains, 63.8 % had antibiotic traits only on one or two of the growth media, whereas only 12.7 % inhibited growth on five or all six media. The application of six different media for antimicrobial testing resulted in twice the number of positive hits as obtained with only a single medium. The use of different media for the isolation of bacteria as well as the variation of media considered suitable for the production of antibiotic substances significantly enhanced both the number of isolates obtained and the proportion of antibiotic active cultures. Thus the approach described herein offers an improved strategy in the search for new antibiotic compounds.

  7. Mutant HbpR transcription activator isolation for 2‐chlorobiphenyl via green fluorescent protein‐based flow cytometry and cell sorting

    PubMed Central

    Beggah, Siham; Vogne, Christelle; Zenaro, Elena; Van Der Meer, Jan Roelof

    2008-01-01

    Summary Mutants were produced in the A‐domain of HbpR, a protein belonging to the XylR family of σ54‐dependent transcription activators, with the purpose of changing its effector recognition specificity from 2‐hydroxybiphenyl (2‐HBP, the cognate effector) to 2‐chlorobiphenyl (2‐CBP). Mutations were introduced in the hbpR gene part for the A‐domain via error‐prone polymerase chain reaction, and assembled on a gene circuitry plasmid in Escherichia coli, permitting HbpR‐dependent induction of the enhanced green fluorescent protein (egfp). Cells with mutant HbpR proteins responsive to 2‐CBP were enriched and separated in a flow cytometry‐assisted cell‐sorting procedure. Some 70 mutants were isolated and the A‐domain mutations mapped. One of these had acquired true 2‐CBP recognition but reacted hypersensitively to 2‐HBP (20‐fold more than the wild type), whereas others had reduced sensitivity to 2‐HBP but a gain of 2‐CBP recognition. Sequencing showed that most mutants carried double or triple mutations in the A‐domain gene part, and were not located in previously recognized conserved residues within the XylR family members. Further selection from a new mutant pool prepared of the hypersensitive mutant did not result in increased 2‐CBP or reduced 2‐HBP recognition. Our data thus demonstrate that a one‐step in vitro‘evolutionary’ adaptation of the HbpR protein can result in both enhancement and reduction of the native effector recognition. PMID:21261823

  8. Species distribution and susceptibility profile of yeasts isolated from blood cultures: results of a multicenter active laboratory-based surveillance study in Argentina.

    PubMed

    Córdoba, Susana; Vivot, Walter; Bosco-Borgeat, Maria E; Taverna, Constanza; Szusz, Wanda; Murisengo, Omar; Isla, Guillermina; Davel, Graciela

    2011-01-01

    The Mycology Department of the Instituto Nacional de Enfermedades Infecciosas "Dr. C. Malbrán", conducted the Second National Multicenter Survey on Fungemia due to Yeasts in Argentina. The aim was to obtain updated data of the frequency of the causative species encountered and their in vitro susceptibility to seven antifungal agents. Yeast species were identified by micromorphological and biochemical studies. Antifungal susceptibility testing was performed by the reference microdilution method E.Def 7.1 of the European Committee on Antibiotic Susceptibility Testing (EUCAST). A total of 461 viable yeasts were identified. The most frequent species were: Candida albicans (38.4 %), Candida parapsilosis (26 %), Candida tropicalis (15.4 %) and Candida glabrata (4.3 %). Other uncommon species, such as Candida viswanathii (0.6 %), Candida haemulonii (0.4 %), Candida inconspicua (0.2 %) and Candida fermentati (0.2 %) were also isolated. Among the Candida spp., 5.4 % and 1.6 % were resistant to fluconazole and voriconazole, respectively. Itraconazole and caspofungin were the most efficient agents against all Candida spp. tested (MIC < 1 mg/l). For anidulafungin, 21.6 % of C. parapsilosis showed a MIC value of 4 mg/l. Fluconazole was less active against 53.1 % of Cryptococcus neoformans (MIC > 8 mg/l), 75 % of Trichosporon spp., and 100 % of Rhodotorula spp., Geotrichum candidum, Saccharomyces cerevisiae. The global percentage of mortality was 20 %. The presence of uncommon species reinforces the need for performing continuous laboratory surveillance in order to monitor possible changes, not only in the epidemiological distribution of species, but also in the resistance to antifungal drugs.

  9. Isolation of Bacteriophages Active Against Neisseria meningitidis

    PubMed Central

    Cary, Sylvia G.; Hunter, Donald H.

    1967-01-01

    Five distinct bacteriophages have been isolated from strains of Neisseria meningitidis. Filtrates with titers of 10−4 to 10−6 were produced with a modified Swanstrom and Adams semisolid agar procedure, employing Eugonbroth with added agar and an incubation temperature of 30 C. Of 49 strains of N. meningitidis (groups B and C), 25 were lysed by one or more of the phages, but there was no lysis of other Neisseria and Mima polymorpha strains. Images PMID:4990042

  10. Isolation of biologically-active exosomes from human plasma.

    PubMed

    Muller, Laurent; Hong, Chang-Sook; Stolz, Donna B; Watkins, Simon C; Whiteside, Theresa L

    2014-09-01

    Effects of exosomes present in human plasma on immune cells have not been examined in detail. Immunological studies with plasma-derived exosomes require their isolation by procedures involving ultracentrifugation. These procedures were largely developed using supernatants of cultured cells. To test biologic activities of plasma-derived exosomes, methods are necessary that ensure adequate recovery of exosome fractions free of contaminating larger vesicles, cell fragments and protein/nucleic acid aggregates. Here, an optimized method for exosome isolation from human plasma/serum specimens of normal controls (NC) or cancer patients and its advantages and pitfalls are described. To remove undesirable plasma-contaminating components, ultrafiltration of differentially-centrifuged plasma/serum followed by size-exclusion chromatography prior to ultracentrifugation facilitated the removal of contaminants. Plasma or serum was equally acceptable as a source of exosomes based on the recovered protein levels (in μg protein/mL plasma) and TEM image quality. Centrifugation on sucrose density gradients led to large exosome losses. Fresh plasma was the best source of morphologically-intact exosomes, while the use of frozen/thawed plasma decreased exosome purity but not their biologic activity. Treatments of frozen plasma with DNAse, RNAse or hyaluronidase did not improve exosome purity and are not recommended. Cancer patients' plasma consistently yielded more isolated exosomes than did NCs' plasma. Cancer patients' exosomes also mediated higher immune suppression as evidenced by decreased CD69 expression on responder CD4+ T effector cells. Thus, the described procedure yields biologically-active, morphologically-intact exosomes that have reasonably good purity without large protein losses and can be used for immunological, biomarker and other studies.

  11. Phytate degrading activities of lactic acid bacteria isolated from traditional fermented food

    NASA Astrophysics Data System (ADS)

    Damayanti, Ema; Ratisiwi, Febiyani Ndaru; Istiqomah, Lusty; Sembiring, Langkah; Febrisiantosa, Andi

    2017-03-01

    The objective of this study was to determine the potential of LAB with phytate degrading activity from fermented traditional food grain-based and legume-based. Lactic acid bacteria were isolated from different sources of traditional fermented food from Gunungkidul Yogyakarta Indonesia such as gembus tempeh (tofu waste), soybean tempeh, lamtoro tempeh (Leucaena bean) and kara tempeh. Isolation of LAB was performed using Total Plate Count (TPC) on de Man Rogosa Sharpe Agar (MRSA) medium supplemented with CaCO3. They were screened for their ability to degrade myo-inositol hexaphosphate or IP6 by using qualitative streak platemethod with modified de Man Rogosa-MorpholinoPropanesulfonic Acid Sharpe (MRS-MOPS) medium contained sodium salt of phytic acid as substrate and cobalt chloride staining (plate assay) method. The selected isolates were further assayed for phytase activities using quantitative method with spectrophotometer and the two selected isolates growth were optimized. Furthermore, thhe isolates that shown the highest phytase activity was characterized and identified using API 50 CH kitand 16S rRNA gene sequencing. The results showed that there were 18 LAB isolates obtained from samplesand 13 isolates were able to degrade sodium phytate based on qualitative screening. According to quantitative assay, the highest phytate degrading activities were found in TG-2(23.562 U/mL) and TG-1 (19.641 U/mL) isolated from gembus tempeh. The phytate activity of TG-2 was optimum at 37 °C with agitation, while the phytate activity of TG-1 was optimum at 45 °C without agitation. Characterization and identification of TG-2 isolate with the highest phytate degrading activity using API 50 CH and 16S rRNA showed that TG-2had homology with Lactobacillus fermentum. It could be concluded that LAB from from fermented traditional food grain-based and legume-based produced the extracellular phytase. Keywords: lactic acid bacteria, tempeh, phytatedegrading activity

  12. Active low-frequency vertical vibration isolation system for precision measurements

    NASA Astrophysics Data System (ADS)

    Wu, Kang; Li, Gang; Hu, Hua; Wang, Lijun

    2017-01-01

    Low-frequency vertical vibration isolation systems play important roles in precision measurements to reduce seismic and environmental vibration noise. Several types of active vibration isolation systems have been developed. However, few researches focus on how to optimize the test mass install position in order to improve the vibration transmissibility. An active low-frequency vertical vibration isolation system based on an earlier instrument, the Super Spring, is designed and implemented. The system, which is simple and compact, consists of two stages: a parallelogram-shaped linkage to ensure vertical motion, and a simple spring-mass system. The theoretical analysis of the vibration isolation system is presented, including terms erroneously ignored before. By carefully choosing the mechanical parameters according to the above analysis and using feedback control, the resonance frequency of the system is reduced from 2.3 to 0.03 Hz, a reduction by a factor of more than 75. The vibration isolation system is installed as an inertial reference in an absolute gravimeter, where it improved the scatter of the absolute gravity values by a factor of 5. The experimental results verifies the improved performance of the isolation system, making it particularly suitable for precision experiments. The improved vertical vibration isolation system can be used as a prototype for designing high-performance active vertical isolation systems. An improved theoretical model of this active vibration isolation system with beam-pivot configuration is proposed, providing fundamental guidelines for vibration isolator design and assembling.

  13. Antibacterial Activities of Actinomycete Isolates Collected from Soils of Rajshahi, Bangladesh

    PubMed Central

    Rahman, Md. Ajijur; Islam, Mohammad Zahidul; Islam, Md. Anwar Ul

    2011-01-01

    This study was performed to isolate actinomycete colonies having antibacterial activity from soil samples collected from different places around Rajshahi, Bangladesh. Thirty actinomycete colonies were isolated in pure culture from five soil samples using Starch-casein-nitrate-agar medium. The isolates were grouped in five color series based on their aerial mycelia color and screened for their antibacterial activity against a range of test bacteria. Sixteen isolates (53.3%) were found to have moderate to high activity against four gram-positive and four gram-negative bacteria. Since many isolates showed inhibitory activity against indicator bacteria, it is suggestive that Bangladeshi soil could be an interesting source to explore for antibacterial secondary metabolites. PMID:21904683

  14. Antileukemia activity in the Osillatoriaceae: isolation of Debromoaplysiatoxin from Lyngbya.

    PubMed

    Mynderse, J S; Moore, R E; Kashiwagi, M; Norton, T R

    1977-04-29

    Chloroform extracts of several seaweeds, of the family Oscillatoriaceae, from Enewetak Atoll, Marshall Islands, display activity against P-388 lymphocytic mouse leukemia. A P-388 active compound, debromoaplysiatoxin, has been isolated from Lyngbya gracilis and characterized. This compound also has dermonecrotic activity and may be the dermatitis-producing substance in L. majuscula, the causative agent of "swimmers' itch" outbreaks in Hawaiian waters.

  15. Glyceollin I, a Novel Antiestrogenic Phytoalexin Isolated from Activated Soy

    PubMed Central

    Zimmermann, M. Carla; Tilghman, Syreeta L.; Boué, Stephen M.; Salvo, Virgilio A.; Elliott, Steven; Williams, K. Y.; Skripnikova, Elena V.; Ashe, Hasina; Payton-Stewart, Florastina; Vanhoy-Rhodes, Lyndsay; Fonseca, Juan Pablo; Corbitt, Cynthia; Collins-Burow, Bridgette M.; Howell, Melanie H.; Lacey, Michelle; Shih, Betty Y.; Carter-Wientjes, Carol; Cleveland, Thomas E.; McLachlan, John A.; Wiese, Thomas E.; Beckman, Barbara S.

    2010-01-01

    Glyceollins, a group of novel phytoalexins isolated from activated soy, have recently been demonstrated to be novel antiestrogens that bind to the estrogen receptor (ER) and inhibit estrogen-induced tumor progression. Our previous publications have focused specifically on inhibition of tumor formation and growth by the glyceollin mixture, which contains three glyceollin isomers (I, II, and III). Here, we show the glyceollin mixture is also effective as a potential antiestrogenic, therapeutic agent that prevents estrogen-stimulated tumorigenesis and displays a differential pattern of gene expression from tamoxifen. By isolating the individual glyceollin isomers (I, II, and III), we have identified the active antiestrogenic component by using competition binding assays with human ERα and in an estrogen-responsive element-based luciferase reporter assay. We identified glyceollin I as the active component of the combined glyceollin mixture. Ligand-receptor modeling (docking) of glyceollin I, II, and III within the ERα ligand binding cavity demonstrates a unique type II antiestrogenic confirmation adopted by glyceollin I but not isomers II and III. We further compared the effects of glyceollin I to the antiestrogens, 4-hydroxytamoxifen and ICI 182,780 (fulvestrant), in MCF-7 breast cancer cells and BG-1 ovarian cancer cells on 17β-estradiol-stimulated expression of progesterone receptor and stromal derived factor-1α. Our results establish a novel inhibition of ER-mediated gene expression and cell proliferation/survival. Glyceollin I may represent an important component of a phytoalexin-enriched food (activated) diet in terms of chemoprevention as well as a novel therapeutic agent for hormone-dependent tumors. PMID:19797619

  16. In vitro activity of voriconazole against Mexican oral yeast isolates.

    PubMed

    Sánchez Vargas, Luis Octavio; Eraso, Elena; Carrillo-Muñoz, Alfonso Javier; Aguirre, José Manuel; Gaitán-Cepeda, Luis Alberto; Quindós, Guillermo

    2010-05-01

    Oral candidiasis is the most prevalent complication in HIV-infected and AIDS patients. Topical antifungal treatment is useful for the initial episodes of oral candidiasis, but most patients suffer more than one episode and fluconazole or itraconazole can help in the management, and voriconazole may represent a useful alternative agent for the treatment of recalcitrant oral and oesophageal candidiasis. The aim of this research was to study the in vitro activity of voriconazole and fluconazole against Mexican oral isolates of clinically relevant yeast. The in vitro susceptibility of 187 oral yeast isolates from HIV-infected and healthy Mexicans was determined for fluconazole and voriconazole by the M44-A disc diffusion method. At 24 h, fluconazole was active against 179 of 187 isolates (95.7 %). Moreover, a 100% susceptibility to voriconazole was observed. Voriconazole and fluconazole are highly active in vitro against oral yeast isolates. This study provides baseline data on susceptibilities to both antifungal agents in Mexico.

  17. Antagonistic Activity of Lactobacillus Isolates against Salmonella typhi In Vitro

    PubMed Central

    Abdel-Daim, Amira; Hassouna, Nadia; Hafez, Mohamed; Ashor, Mohamed Seif Aldeen; Aboulwafa, Mohammad M.

    2013-01-01

    Background. Enteric fever is a global health problem, and rapidly developing resistance to various drugs makes the situation more alarming. The potential use of Lactobacillus to control typhoid fever represents a promising approach, as it may exert protective actions through various mechanisms. Methods. In this study, the probiotic potential and antagonistic activities of 32 Lactobacillus isolates against Salmonella typhi were evaluated. The antimicrobial activity of cell free supernatants of Lactobacillus isolates, interference of Lactobacillus isolates with the Salmonella adherence and invasion, cytoprotective effect of Lactobacillus isolates, and possibility of concurrent use of tested Lactobacillus isolates and antibiotics were evaluated by testing their susceptibilities to antimicrobial agents, and their oxygen tolerance was also examined. Results. The results revealed that twelve Lactobacillus isolates could protect against Salmonella typhi infection through interference with both its growth and its virulence properties, such as adherence, invasion, and cytotoxicity. These Lactobacillus isolates exhibited MIC values for ciprofloxacin higher than those of Salmonella typhi and oxygen tolerance and were identified as Lactobacillus plantarum. Conclusion. The tested Lactobacillus plantarum isolates can be introduced as potential novel candidates that have to be subjected for in vivo and application studies for treatment and control of typhoid fever. PMID:24191248

  18. Validation of a "Kane's Dynamics" Model for the Active Rack Isolation System

    NASA Technical Reports Server (NTRS)

    Beech, Geoffrey S.; Hampton, R. David

    2000-01-01

    Many microgravity space-science experiments require vibratory acceleration levels unachievable without active isolation. The Boeing Corporation's Active Rack Isolation System (ARIS) employs a novel combination of magnetic actuation and mechanical linkages, to address these isolation requirements on the International Space Station (ISS). ARIS provides isolation at the rack (international Standard Payload Rack, or ISPR) level. Effective model-based vibration isolation requires (1) an isolation device, (2) an adequate dynamic (i.e., mathematical) model of that isolator, and (3) a suitable, corresponding controller, ARIS provides the ISS response to the first requirement. In November 1999, the authors presented a response to the second ("A 'Kane's Dynamics' model for the Active Rack Isolation System", Hampton and Beech) intended to facilitate an optimal-controls approach to the third. This paper documents the validation of that high-fidelity dynamic model of ARIS. As before, this model contains the full actuator dynamics, however, the umbilical models are not included in this presentation. The validation of this dynamics model was achieved by utilizing two Commercial Off the Shelf (COTS) software tools: Deneb's ENVISION, and Online Dynamics' AUTOLEV. ENVISION is a robotics software package developed for the automotive industry that employs 3-dimensional (3-D) Computer Aided Design (CAD) models to facilitate both forward and inverse kinematics analyses. AUTOLEV is a DOS based interpreter that is designed in general to solve vector based mathematical problems and specifically to solve Dynamics problems using Kane's method.

  19. Cytotoxic activity and molecular docking of a novel biflavonoid isolated from Jacaranda acutifolia (Bignoniaceae).

    PubMed

    Mostafa, Nada M; Ashour, Mohamed L; Eldahshan, Omayma A; Singab, Abdel Nasser B

    2016-09-01

    A novel biflavonoid [kaempferol (6→8″) apigenin] was isolated from the leaves of Jacaranda acutifolia. The structure was elucidated based on chemical evidence, 1D and 2D spectroscopic analyses as well as spectrometric techniques. The compound showed promising cytotoxic activity against breast cancer cell line MCF-7. The anticancer activity was explained via virtual docking of the isolated compound to the main sites in the human cyclin-dependent kinase2 (CDK2) crystal structure.

  20. 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

  1. Inhibition of p38 MAPK during cellular activation modulate gene expression of head kidney leukocytes isolated from Atlantic salmon (Salmo salar) fed soy bean oil or fish oil based diets.

    PubMed

    Holen, E; Winterthun, S; Du, Z-Y; Krøvel, A V

    2011-01-01

    Head kidney leukocytes isolated from Atlantic salmon fed either a diet based on fish oil (FO) or soy bean oil (VO) were used in order to evaluate if different lipid sources could contribute to cellular activation of the salmon innate immune system. A specific inhibitor of p38 MAPK, SB202190, was used to investigate the effect of lipopolysaccharide (LPS) signalling in the head kidney leukocytes. The results show that LPS up regulate IL-1β, TNF-α, Cox2 expression in leukocytes isolated from fish fed either diet. The p38 MAPK inhibitor, SB202190, reduced the LPS induced expression of these genes in both dietary groups. In LPS stimulated leukocytes isolated from VO fed fish, SB202190 showed a clear dose dependent inhibitory effect on IL-1β, TNF-α and Cox2 expression. This effect was also observed for Cox2 in leukocytes isolated from FO fed fish. Furthermore, there was a stronger mean induction of Cox2 in LPS stimulated leucocytes isolated from the VO-group compared to LPS stimulated leukocytes isolated from the FO-group. In both dietary groups, LPS stimulation of salmon head kidney leukocytes increased the induction of CD83, a dendrite cell marker, while the inhibitor reduced CD83 expression in the VO fed fish only. The inhibitor also clearly reduced hsp27 expression in VO fed fish. Indicating a p38 MAPK feedback loop, LPS significantly inhibited the expression of p38MAPK itself in both diets, while SB202190 increased p38MAPK expression especially in the VO diet group. hsp70 expression was not affected by any treatment or feed composition. There were also differences in p38MAPK protein phosphorylation comparing treatment groups but no obvious difference comparing the two dietary groups. The results indicate that dietary fatty acids have the ability to modify signalling through p38 MAPK which may have consequences for the fish's ability to handle infections and stress. Signalling through p38MAPK is ligand dependent and affects gene and protein expression differently.

  2. Antimetastatic activity isolated from Colocasia esculenta (taro).

    PubMed

    Kundu, Namita; Campbell, Patricia; Hampton, Brian; Lin, Chen-Yong; Ma, Xinrong; Ambulos, Nicholas; Zhao, X Frank; Goloubeva, Olga; Holt, Dawn; Fulton, Amy M

    2012-02-01

    Breast cancer mortality is primarily due to the occurrence of metastatic disease. We have identified a novel potential therapeutic agent derived from an edible root of the plant Colocasia esculenta, commonly known as taro, which has demonstrable activity in a preclinical model of metastatic breast cancer and that should have minimal toxicity. We have shown for the first time that a water-soluble extract of taro (TE) potently inhibits lung-colonizing ability and spontaneous metastasis from mammary gland-implanted tumors, in a murine model of highly metastatic estrogen receptor, progesterone receptor and Her-2/neu-negative breast cancer. TE modestly inhibits the proliferation of some, but not all, breast and prostate cancer cell lines. Morphological changes including cell rounding were observed. Tumor cell migration was completely blocked by TE. TE treatment also inhibited prostaglandin E2 (PGE2) synthesis and downregulated cyclooxygenase 1 and 2 mRNA expression. We purified the active compound(s) to near homogeneity with antimetastatic activity comparable with stock TE. The active compound with a native size of approximately 25 kDa contains two fragments of nearly equal size. The N-terminal amino acid sequencing of both fragments reveals that the active compound is highly related to three taro proteins: 12-kDa storage protein, tarin and taro lectin. All are similar in terms of amino acid sequence, posttranslational processing and all contain a carbohydrate-binding domain. This is the first report describing compound(s) derived from taro that potently and specifically inhibits tumor metastasis.

  3. Antitrypanosomal activity of some pregnane glycosides isolated from Caralluma species.

    PubMed

    Abdel-Sattar, Essam; Shehab, Naglaa G; Ichino, Chikara; Kiyohara, Hiroaki; Ishiyama, Aki; Otoguro, Kazuhiko; Omura, Satoshi; Yamada, Haruki

    2009-06-01

    Pregnane glycosides previously isolated from genus Caralluma (C. Penicillata, C. tuberculata and C. russelliana) were tested for their antitrypanosomal activity. Penicilloside E showed the highest antitrypanosomal activity (IC(50) 1.01 microg/ml) followed by caratuberside C (IC(50) 1.85 microg/ml), which exhibited the highest selectivity index (SI 12.04). It was noticed that acylation is required for the antitrypanosomal activity while glycosylation at C-20 has no significant effect on the activity.

  4. Faraday isolator based on TSAG crystal for high power lasers.

    PubMed

    Mironov, E A; Palashov, O V

    2014-09-22

    A Faraday isolator based on a new magneto-optical medium, TSAG (terbium scandium aluminum garnet) crystal, has been constructed and investigated experimentally. The device provides an isolation ratio of more than 30 dB at 500 W laser power. It is shown that this medium can be used in Faraday isolators for kilowatt-level laser powers.

  5. Active transmission isolation/rotor loads measurement system

    NASA Technical Reports Server (NTRS)

    Kenigsberg, I. J.; Defelice, J. J.

    1973-01-01

    Modifications were incorporated into a helicopter active transmission isolation system to provide the capability of utilizing the system as a rotor force measuring device. These included; (1) isolator redesign to improve operation and minimize friction, (2) installation of pressure transducers in each isolator, and (3) load cells in series with each torque restraint link. Full scale vibration tests performed during this study on a CH-53A helicopter airframe verified that these modifications do not degrade the systems wide band isolation characteristics. Bench tests performed on each isolator unit indicated that steady and transient loads can be measured to within 1 percent of applied load. Individual isolator vibratory load measurement accuracy was determined to be 4 percent. Load measurement accuracy was found to be independent of variations in all basic isolator operating characteristics. Full scale system load calibration tests on the CH-53A airframe established the feasibility of simultaneously providing wide band vibration isolation and accurate measurement of rotor loads. Principal rotor loads (lift, propulsive force, and torque) were measured to within 2 percent of applied load.

  6. Electromechanical Modelling of an Active Isolation System

    DTIC Science & Technology

    1991-04-01

    Department of Mechanical Engineering, Auburn University, Auburn , AL 36849, U.S.A. Active Control of Automobile Two-Stage Suspension System-Half Car Model...element model ..... one d.imensnional modelo -ilo0- S-120 1 L 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 Frequency(f/fO) 6(b) Sensor Voltage S20 10 16

  7. Antimalarial activity of nepodin isolated from Rumex crispus.

    PubMed

    Lee, Keyong Ho; Rhee, Ki-Hyeong

    2013-04-01

    The purpose of this study is to define the antimalarial activity of Rumex crispus. To identify an active compound that is isolated from R. crispus, bioassay-based chromatographic fractionation and purification is carried out from 70 % ethanol extract of R. crispus; then, an active compound, nepodin, is identified by spectroscopic analysis. Anitmalarial activity is measured by PfNDH2 assay, cytotoxicity, and animal test. From NADH:quinone oxidoreductase enzyme (PfNDAH2) assay, nepodin exhibited significant IC50 values that were 0.74 ± 0.07 and 0.79 ± 0.06 μg/ml against P. falciparum chloroquine-sensitive (3D7) and P. falciparum chloroquine-resistant (S20), respectively. Nepodin showed a potential selective inhibition (SI index: ratio of 50 % cytotoxic concentration to 50 % effective anti-plasmodial concentration) of 161.6 and 151.4 against P. falciparum 3D7 and P. falciparum S20. In the animal test, all groups of nepodin treatment of 10, 50, and 250 mg/kg were active with a parasitemia suppression of 97.1 ± 3.3, 99.1 ± 3.7, and 99.1 ± 2.6 %, respectively. The survival time with nepodin treatment was increased by 14.6 ± 2.5, 16.2 ± 1.5, and 19.8 ± 1.7 days at each dose, respectively. This study newly identified the plant R. crispus containing nepodin, which is a potential antimalarial compound. It exhibited the inhibitory activity of PfNDH2 and prolonged the survival time on the group of nepodin treatment; moreover, it inhibited the parasitemia in the animal test.

  8. Status recognition of isolator based on SmartGuard

    NASA Astrophysics Data System (ADS)

    Wang, Wanguo; Wang, Binhai; Wang, Zhenli; Li, Li; Zhang, Jingjing; Li, Yibin

    2013-07-01

    This paper concerns the method for checking the status of isolators and is applied in the sequence control in smart substation based on SmartGuard--a mobile inspection robot for substations. It can recognize the status of an isolator through analyzing its feature. We could get the homography matrix by using the SIFT feature between the template image and new acquired image, then get the range of isolator, finally recognize the status of isolator by image processing. The experiment of results proved that the method could recognize isolator status effectively. The substation realizes one key sequence control system through this technology based SmartGuard.

  9. Activity of coumermycin against clinical isolates of staphylococci.

    PubMed Central

    Guillemin, M N; Miles, H M; McDonald, M I

    1986-01-01

    Staphylococci, particularly methicillin-resistant strains of Staphylococcus aureus, are major nosocomial pathogens in large hospitals in eastern Australia. At present vancomycin is the drug of choice for the treatment of life-threatening methicillin-resistant S. aureus infections. A possible alternative drug is coumermycin, a bis-hydroxy coumarin which inhibits DNA gyrase. Coumermycin activity was determined against clinical isolates from the Royal Melbourne Hospital. MICs of 639 staphylococcal isolates were determined by agar dilution. MICs and MBCs of 100 staphylococcal isolates were also determined by microdilution methods. The results showed that coumermycin was bactericidal, with MBCs of less than or equal to 4 micrograms/ml against all isolates tested. The results indicate that coumermycin is a potential alternative to vancomycin in the treatment of severe staphylococcal infections. PMID:3707109

  10. Enzyme activities in mitochondria isolated from ripening tomato fruit.

    PubMed

    Jeffery, D; Goodenough, P W; Weitzman, P D

    1986-09-01

    Mitochondria were isolated from tomato (Lycopersicon esculentum L.) fruit at the mature green, orange-green and red stages and from fruit artificially suspended in their ripening stage. The specific activities of citrate synthase (EC 4.1.3.7), malate dehydrogenase (EC 1.1.1.37), NAD-linked isocitrate dehydrogenase (EC 1.1.1.41) and NAD-linked malic enzyme (EC 1.1.1.38) were determined. The specific activities of all these enzymes fell during ipening, although the mitochondria were fully functional as demonstrated by the uptake of oxygen. The fall in activity of mitochondrial malate dehydrogenase was accompanied by a similar fall in the activity of the cytosolic isoenzyme. Percoll-purified mitochondria isolated from mature green fruit remained intact for more than one week and at least one enzyme, citrate synthase, did not exhibit the fall in specific activity found in normal ripening fruit.

  11. Candida albicans isolates from a Malaysian hospital exhibit more potent phospholipase and haemolysin activities than non-albicans Candida isolates.

    PubMed

    Chin, V K; Foong, K J; Maha, A; Rusliza, B; Norhafizah, M; Ng, K P; Chong, P P

    2013-12-01

    This study was aimed at determining the phospholipase and haemolysin activity of Candida isolates in Malaysia. A total of 37 Candida clinical isolates representing seven species, Candida albicans (12), Candida tropicalis (8), Candida glabrata (4), Candida parapsilosis (1), Candida krusei (4), Candida orthopsilosis (1) and Candida rugosa (7) were tested. In vitro phospholipase activity was determined by using egg yolk plate assay whereas in vitro haemolysin activity was tested by using blood plate assay on sheep blood Sabouraud's dextrose agar (SDA) enriched with glucose. Phospholipase activity was detected in 75% (9 out of 12) of the C. albicans isolates. Among the 25 non- C. albicans Candida isolates, phospholipase activity was detected in only 24% of these isolates. The phospholipase activity of C. albicans was significantly higher than that of the non- C. albicans Candida isolates (P=0.002). Haemolysin activity was detected in 100% of the C. albicans, C. tropicalis, C. glabrata, C. krusei, C. parapsilosis, and C. orthopsilosis isolates while 75% of the C. krusei isolates and 12.3% of the C. rugosa isolates showed haemolysin activity. The haemolytic activity of C. albicans was significantly higher than that of the non- C. albicans Candida isolates (P=0.0001).The findings in this study indicate that C. albicans isolates in Malaysia may possess greater virulence potential than the non-albicans species.

  12. Effects of antifungal agents in sap activity of Candida albicans isolates.

    PubMed

    Costa, Carolina Rodrigues; Jesuíno, Rosália Santos Amorim; de Aquino Lemos, Janine; de Fátima Lisboa Fernandes, Orionalda; Hasimoto e Souza, Lúcia Kioko; Passos, Xisto Sena; do Rosário Rodrigues Silva, Maria

    2010-02-01

    Some antifungal agents have shown to exert effects on expression of virulent factors of Candida as the production of secretory aspartyl proteinase (Sap). In this study, we sought to determine and to compare the influence of fluconazole and voriconazole in proteinase activity of this microorganism. Thirty-one isolates obtained from oral mucosa of human immunodeficiency virus positive (HIV) patients were used in this study. The minimal inhibitory concentrations (MIC) of fluconazole and voriconazole were determined using the broth microdilution method with RPMI 1640 medium and with yeast carbon base-bovine serum albumin (YCB-BSA) medium. The Sap activity following by digestion of BSA as substrate was determined for four Candida albicans strains arbitrarily chosen according to susceptibility (susceptible or resistant) to fluconazole or voriconazole. Besides, the SAP1 to SAP7 genes were screened by PCR for the same isolates that were determined by the Sap activity. In vitro susceptibility testing using the two media presented similar MIC values. Increased Sap activity was observed in resistant isolates on presence of drugs, but the Sap activity by susceptible isolates to azoles showed different behavior on the presence of drug. We detected the presence of SAP1 to SAP7 genes from all susceptible or resistant C. albicans isolates. The present study provides important data about the proteinase activity and the presence of genes of SAP family in fluconazole and voriconazole susceptible or resistant C. albicans isolates.

  13. Isolation of active regulatory elements from eukaryotic chromatin using FAIRE (Formaldehyde Assisted Isolation of Regulatory Elements)

    PubMed Central

    Giresi, Paul G.; Lieb, Jason D.

    2009-01-01

    The binding of sequence-specific regulatory factors and the recruitment of chromatin remodeling activities cause nucleosomes to be evicted from chromatin in eukaryotic cells. Traditionally, these active sites have been identified experimentally through their sensitivity to nucleases. Here we describe the details of a simple procedure for the genome-wide isolation of nucleosome-depleted DNA from human chromatin, termed FAIRE (Formaldehyde Assisted Isolation of Regulatory Elements). We also provide protocols for different methods of detecting FAIRE-enriched DNA, including use of PCR, DNA microarrays, and next-generation sequencing. FAIRE works on all eukaryotic chromatin tested to date. To perform FAIRE, chromatin is crosslinked with formaldehyde, sheared by sonication, and phenol-chloroform extracted. Most genomic DNA is crosslinked to nucleosomes and is sequestered to the interphase, whereas DNA recovered in the aqueous phase corresponds to nucleosome-depleted regions of the genome. The isolated regions are largely coincident with the location of DNaseI hypersensitive sites, transcriptional start sites, enhancers, insulators, and active promoters. Given its speed and simplicity, FAIRE has utility in establishing chromatin profiles of diverse cell types in health and disease, isolating DNA regulatory elements en masse for further characterization, and as a screening assay for the effects of small molecules on chromatin organization. PMID:19303047

  14. Glyceollin I, A Novel Antiestrogenic Phytoalexin Isolated from Activated Soy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glyceollins, a group of novel phytoalexins isolated from activated soy, have recently been demonstrated to be a novel antiestrogen which bind to the estrogen receptor (ER) and inhibit estrogen-induced tumor progression. Our previous publications have focused specifically on inhibition of tumor form...

  15. Passive base isolation with superelastic nitinol SMA helical springs

    NASA Astrophysics Data System (ADS)

    Huang, Bin; Zhang, Haiyang; Wang, Han; Song, Gangbing

    2014-06-01

    Seismic isolation of structures such as multi-story buildings, nuclear reactors, bridges, and liquid storage tanks should be designed to preserve structural integrity. By implementing seismic isolation technology, the deformation of superstructures can be dramatically reduced, consequently helping to protect their safety as well. In this paper, an innovative type of passive base isolation system, which is mainly composed of superelastic nitinol SMA helical springs, is developed. In order to verify the effectiveness of the proposed system, a two-story experimental steel frame model is constructed, and two superelastic SMA helical springs are thermo-mechanically built in the laboratory. To describe the nonlinear mechanical properties of the superelastic SMA helical springs under reciprocating load, a phenomenological model is presented in terms of a series of tensile tests. Afterwards, a numerical model of the two-story frame with the suggested isolation system is set up to simulate the response of the isolated frame subjected to an earthquake. Both the experimental and the numerical simulation results indicate that the proposed base isolation system can remarkably suppress structural vibrations and has improved isolation effects when compared with a steel spring isolation system. Due to the capabilities of energy dissipation as well as fully re-centering, it is very applicable to utilize the suggested isolation system in base isolated structures to resist earthquakes.

  16. Isolation, identification and antimicrobial activity of propolis-associated fungi.

    PubMed

    de Souza, Giovanni Gontijo; Pfenning, Ludwig Heinrich; de Moura, Fabiana; Salgado, Mírian; Takahashi, Jacqueline Aparecida

    2013-01-01

    Propolis is a natural product widely known for its medicinal properties. In this work, fungi present on propolis samples were isolated, identified and tested for the production of antimicrobial metabolites. Twenty-two fungal isolates were obtained, some of which were identified as Alternaria alternata, Aspergillus flavus, Bipolaris hawaiiensis, Fusarium merismoides, Lasiodiplodia theobromae, Penicillium citrinum, Penicillium crustosum, Penicillium janthinellum, Penicillium purpurogenum, Pestalotiopsis palustris, Tetracoccosporium paxianum and Trichoderma koningii. These fungi were grown in liquid media to obtain crude extracts that were evaluated for their antibiotic activity against pathogenic bacteria, yeast and Cladosporium cladosporioides and A. flavus. The most active extract was obtained from L. theobromae (minimum inhibitory concentration = 64 μg/mL against Listeria monocitogenes). Some extracts showed to be more active than the positive control in the inhibition of Staphylococcus aureus and L. monocitogenes. Therefore, propolis is a promising source of fungi, which produces active agents against relevant food poisoning bacteria and crop-associated fungi.

  17. FAIRE (Formaldehyde-Assisted Isolation of Regulatory Elements) isolates active regulatory elements from human chromatin

    PubMed Central

    Giresi, Paul G.; Kim, Jonghwan; McDaniell, Ryan M.; Iyer, Vishwanath R.; Lieb, Jason D.

    2007-01-01

    DNA segments that actively regulate transcription in vivo are typically characterized by eviction of nucleosomes from chromatin and are experimentally identified by their hypersensitivity to nucleases. Here we demonstrate a simple procedure for the isolation of nucleosome-depleted DNA from human chromatin, termed FAIRE (Formaldehyde-Assisted Isolation of Regulatory Elements). To perform FAIRE, chromatin is crosslinked with formaldehyde in vivo, sheared by sonication, and phenol-chloroform extracted. The DNA recovered in the aqueous phase is fluorescently labeled and hybridized to a DNA microarray. FAIRE performed in human cells strongly enriches DNA coincident with the location of DNaseI hypersensitive sites, transcriptional start sites, and active promoters. Evidence for cell-type–specific patterns of FAIRE enrichment is also presented. FAIRE has utility as a positive selection for genomic regions associated with regulatory activity, including regions traditionally detected by nuclease hypersensitivity assays. PMID:17179217

  18. Antifeedant activity of anticopalic acid isolated from Vitex hemsleyi.

    PubMed

    Villegas Gómez, Clarisa; Martínez-Vázquez, Mariano; Esquivel, Baldomero

    2009-01-01

    The known labdane-type diterpenoids anticopalic acid (1) and 3 beta-hydroxyanticopalic acid (2) were isolated from extracts of the aerial parts of Vitex hemsleyi Briq. (Labiatae). The acid 1 showed an antifeedant, dose-dependent activity against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae). To our knowledge this is the first report on the antifeedant activity of a labdane-type diterpene against S. frugiperda.

  19. Estrogenic activity of furanocoumarins isolated from Angelica dahurica.

    PubMed

    Piao, Xiang Lan; Yoo, Hye Hyun; Kim, Hyun Young; Kang, Tak Lim; Hwang, Gwi Seo; Park, Jeong Hill

    2006-09-01

    In our efforts to discover novel phytoestrogens to treat menopausal symptoms, eleven furanocoumarins were isolated from Angelica dahurica and tested for their estrogenic activity on the Ishikawa cell line. Among the compounds tested, 9-hydroxy-4-methoxypsoralen and alloisoimperatorin showed strong abilities to induce alkaline phosphatase (AP) with EC50 values of 1.1 and 0.8 microg/mL, respectively, whereas the other nine furanocoumarins were weakly or only slightly active.

  20. Antimicrobial activity of Bacillus sp. strain FAS1 isolated from soil.

    PubMed

    Moshafi, Mohammad Hasan; Forootanfar, Hamid; Ameri, Alieh; Ameri, Alieh; Shakibaie, Mojtaba; Dehghan-Noudeh, Gholamreza; Razavi, Mojdeh

    2011-07-01

    During screening for antibiotic producing microorganisms from environmental soil samples, the supernatant of a bacterial isolate was found to have antibacterial and antifungal activity on the standard indicator species. The standard cylinder-plate method was used to determine the inhibitory effect of the crude supernatant of each isolate on 6 bacterial and 3 fungal standard strains by measuring the diameter of inhibition zone. The highest inhibition zone on Aspergillus niger belonged to culture broth of isolate FAS1 by 25 mm, and this isolate was the most efficient microorganism to inhibit standard bacterial and fungal species. Based on morphological and biochemical properties as well as 16S rDNA gene analysis, the selected isolate (isolate FAS(1)) belonged to Bacillus genus. Investigation on the ability of different culture media for antibiotic production led to select Luria-Bertani media for further studies. Treatment of the culture broth of the isolate FAS(1) using typical protease didn't decrease the antimicrobial activity of the supernatant. After extracting of culture broth of the selected isolate by ethyl acetate as an organic solvent, the inhibitory effect was mainly increased. More investigation was done by bioautography method where the ethyl acetate fraction of the broth culture was separated on TLC by chloroform:methanol, 60:40 as mobile phase and R(f) were calculated for inhibition spots.

  1. Isolation of Bacillus amyloliquefaciens Strains with Antifungal Activities from Meju

    PubMed Central

    Lee, Hwang A; Kim, Jeong Hwan

    2012-01-01

    Bacilli with fibrinolytic activities were isolated from traditionally-prepared Meju and some of these strains showed strong antifungal activities. One isolate, MJ1-4, showed the strongest antifungal activity. MJ1-4 and other isolates were identified as B. amyloliquefaciens strains by recA gene sequencing and RAPD-PCR results. B. amyloliqufaciens MJ1-4 efficiently inhibited an Aspergillus spp.-producing aflatoxin B1 (AFB1) and a Penicillium spp.-producing ochratoxin (OTA) in addition to other fungi. Antifungal activity of B. amyloliquefaciens MJ1-4 culture reached its maximum (40 AU/mg protein) in LB or TSB medium around 48 hr at 37°C. Antifungal activity of the concentrated culture supernatant was not decreased significantly by protease treatments, implying that the antifungal substance might not be a simple peptide or protein. Considering its antifungal and fibrinolytic activities together, B. amyloliquefaciens MJ1-4 can serve as a starter for fermented soyfoods such as Cheonggukjang and Doenjang. PMID:24471064

  2. L-Asparaginase Activity in Cell Lysates and Culture Media of Halophilic Bacterial Isolates

    PubMed Central

    Barati, Mahmood; Faramarzi, Mohammad Ali; Nafissi-Varcheh, Nastaran; Khoshayand, Mohammad Reza; Houshdar Tehrani, Mohammad Hassan; Vahidi, Hossein; Adrangi, Sina

    2016-01-01

    The objective of this study was to isolate halophilic bacteria with the ability to produce intracellular or extracellular L-asparaginase. A total number of 120 halophilic bacteria were isolated from 17 different saline habitats of Iran including salt lakes, wetlands, brine springs and deserts. Among these, 68 were able to grow in the presence of 1.5 M NaCl and 52 demonstrated the ability to grow in the selection medium containing 3.5 M NaCl. None of the isolates appeared to produce appreciable amounts of extracellular L-asparaginase. Among the isolates that produced intracellular L-asparaginase, 5 moderate and 1 extreme halophiles were selected for further study based on their observed activity level. The moderately halophilic isolates were shown to belong to the genus Halomonas while the extreme halophile was identified as a member of the genus Aidingimonas. PMID:27980578

  3. L-Asparaginase Activity in Cell Lysates and Culture Media of Halophilic Bacterial Isolates.

    PubMed

    Barati, Mahmood; Faramarzi, Mohammad Ali; Nafissi-Varcheh, Nastaran; Khoshayand, Mohammad Reza; Houshdar Tehrani, Mohammad Hassan; Vahidi, Hossein; Adrangi, Sina

    2016-01-01

    The objective of this study was to isolate halophilic bacteria with the ability to produce intracellular or extracellular L-asparaginase. A total number of 120 halophilic bacteria were isolated from 17 different saline habitats of Iran including salt lakes, wetlands, brine springs and deserts. Among these, 68 were able to grow in the presence of 1.5 M NaCl and 52 demonstrated the ability to grow in the selection medium containing 3.5 M NaCl. None of the isolates appeared to produce appreciable amounts of extracellular L-asparaginase. Among the isolates that produced intracellular L-asparaginase, 5 moderate and 1 extreme halophiles were selected for further study based on their observed activity level. The moderately halophilic isolates were shown to belong to the genus Halomonas while the extreme halophile was identified as a member of the genus Aidingimonas.

  4. [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.

  5. Isolation of a lead tolerant novel bacterial species, Achromobacter sp. TL-3: assessment of bioflocculant activity.

    PubMed

    Batta, Neha; Subudhi, Sanjukta; Lal, Banwari; Devi, Arundhuti

    2013-11-01

    Lead is one of the four heavy metals that has a profound damaging effects on human health. In the recent past there has been an increasing global concern for development of sustainable bioremediation technologies for detoxification of lead contaminant. Present investigation highlights for lead biosorption by a newly isolated novel bacterial species; Achromobacter sp. TL-3 strain, isolated from activated sludge samples contaminated with heavy metals (collected from oil refinery, Assam, North-East India). For isolation of lead tolerant bacteria, sludge samples were enriched into Luria Broth medium supplemented separately with a range of lead nitrate; 250, 500, 750, 1000, 1250 and 1500 ppm respectively. The bacterial consortium that could tolerate 1500 ppm of lead nitrate was selected further for purification of lead tolerant bacterial isolates. Purified lead tolerant bacterial isolates were then eventually inoculated into production medium supplemented with ethanol and glycerol as carbon and energy source to investigate for bioflocculant production. Bioflocculant production was estimated by monitoring the potential of lead tolerant bacterial isolate to flocculate Kaolin clay in presence of 1% CaCl2. Compared to other isolates, TL-3 isolate demonstrated for maximum bioflocculant activity of 95% and thus was identified based on 16S rRNA gene sequence analysis. TL3 isolate revealed maximum homology (98%) with Achromobacter sp. and thus designated as Achromobacter sp. TL-3. Bioflocculant activity of TL-3 isolate was correlated with the change in pH and growth. Achromobacter sp. TL-3 has significant potential for lead biosorption and can be effectively employed for detoxification of lead contaminated waste effluents/waste waters.

  6. Bioassay-based isolation and identification of phenolics from sweet cherry that promote active glucose consumption by HepG2 cells.

    PubMed

    Cao, Jinping; Li, Xin; Liu, Yunxi; Leng, Feng; Li, Xian; Sun, Chongde; Chen, Kunsong

    2015-02-01

    A variety of phenolics had been found to be functional in promoting cellular glucose consumption that is important for blood glucose regulation. Sweet cherry (Prunus avium) is rich in such kinds of phenolics, including hydrocinnamic acids, anthocyanins, flavonols, and flavan-3-ols. Furthermore, a sweet cherry phenolics-rich extract (PRE) was found to be effective in promoting HepG2 glucose consumption. Seventeen components were preliminarily identified by HPLC-ESI-MS, including 9 hydrocinnamic acids, 4 anthocyanins, 3 flavonols, and 1 flavan-3-ol. To investigate the cellular glucose consumption-promotion activity of different phneolics subclasses, the phenolics were further fractionated into an anthocyanin-rich fraction (ARF), hydrocinnamic acid-rich fraction (HRF), and flavonol-rich fraction (FRF) through liquid-liquid extraction and mix-mode cation-exchange solid-phase extraction. The 3 fractions promoted HepG2 glucose consumption to different levels, with the promotion effects of HRF and FRF stronger than that of the ARF. The results provide guidance on the use of sweet cherry as a functional fruit.

  7. Optimum Damping in a Non-Linear Base Isolation System

    NASA Astrophysics Data System (ADS)

    Jangid, R. S.

    1996-02-01

    Optimum isolation damping for minimum acceleration of a base-isolated structure subjected to earthquake ground excitation is investigated. The stochastic model of the El-Centro1940 earthquake, which preserves the non-stationary evolution of amplitude and frequency content of ground motion, is used as an earthquake excitation. The base isolated structure consists of a linear flexible shear type multi-storey building supported on a base isolation system. The resilient-friction base isolator (R-FBI) is considered as an isolation system. The non-stationary stochastic response of the system is obtained by the time dependent equivalent linearization technique as the force-deformation of the R-FBI system is non-linear. The optimum damping of the R-FBI system is obtained under important parametric variations; i.e., the coefficient of friction of the R-FBI system, the period and damping of the superstructure; the effective period of base isolation. The criterion selected for optimality is the minimization of the top floor root mean square (r.m.s.) acceleration. It is shown that the above parameters have significant effects on optimum isolation damping.

  8. Chloride transport in functionally active phagosomes isolated from Human neutrophils

    PubMed Central

    Aiken, Martha L.; Painter, Richard G.; Zhou, Yun; Wang, Guoshun

    2012-01-01

    Chloride anion is critical for hypochlorous acid (HOCl) production and microbial killing in neutrophil phagosomes. However, the molecular mechanism by which this anion is transported to the organelle is poorly understood. In this report, membrane-enclosed and functionally active phagosomes were isolated from human neutrophils by using opsonized paramagnetic latex microspheres and a rapid magnetic separation method. The phagosomes recovered were highly enriched for specific protein markers associated with this organelle such as lysosomal-associated membrane protein-1, myeloperoxidase (MPO), lactoferrin, and NADPH oxidase. When FITC–dextran was included in the phagocytosis medium, the majority of the isolated phagosomes retained the fluorescent label after isolation, indicative of intact membrane structure. Flow cytometric measurement of acridine orange, a fluorescent pH indicator, in the purified phagosomes demonstrated that the organelle in its isolated state was capable of transporting protons to the phagosomal lumen via the vacuolar-type ATPase proton pump (V-ATPase). When NADPH was supplied, the isolated phagosomes constitutively oxidized dihydrorhodamine 123, indicating their ability to produce hydrogen peroxide. The preparations also showed a robust production of HOCl within the phagosomal lumen when assayed with the HOCl-specific fluorescent probe R19-S by flow cytometry. MPO-mediated iodination of the proteins covalently conjugated to the phagocytosed beads was quantitatively measured. Phagosomal uptake of iodide and protein iodination were significantly blocked by chloride channel inhibitors, including CFTRinh-172 and NPPB. Further experiments determined that the V-ATPase-driving proton flux into the isolated phagosomes required chloride cotransport, and the cAMP-activated CFTR chloride channel was a major contributor to the chloride transport. Taken together, the data suggest that the phagosomal preparation described herein retains ion transport

  9. Anti-proliferative activities of terpenoids isolated from Alisma orientalis and their structure-activity relationships.

    PubMed

    Xu, Wen; Li, Ting; Qiu, Jian-Fang; Wu, Shui-Sheng; Huang, Ming-Qing; Lin, Li-Gen; Zhang, Qing-Wen; Chen, Xiu-Ping; Lu, Jin-Jian

    2015-01-01

    This study aimed to isolate terpenoids from Alisma orientalis (Sam.) Juzep. and elucidate their antiproliferative activities, as well as structure-activity relationships. Fourteen protostane-type triterpenoids were isolated from the rhizome of A. orientalis. Among these triterpenoids, alisol A (1), alisol A 24-acetate (2), alisol B (3), alisol B 23-acetate (4), and alisol G (8) presented inhibitory effects on cancer cell lines tested. Compounds 3 and 4 showed the highest potential; IC50 values for HepG2, MDA-MB-231, and MCF-7 cells were 16.28, 14.47, and 6.66 μM for 3 and 18.01, 15.97, and 13.56 μM for 4, respectively. Based on these results, we concluded that the degree of C-16 oxidation and the double bond between C-13 and C-17 may be significant in anti-proliferative activities. Further study showed that 3 and 4 effectively induced apoptosis, as confirmed by flow cytometry. Increased intracellular calcium concentration and endoplasmic reticulum stress were detected after treatment with 4 in HepG2 cells. Although compounds 1 and 2 induced minimal apoptosis, they evidently delayed the G2/M phase in HepG2 cells. Further study showed that 1-4 also enhanced LC3II expression, indicating autophagy is occured.

  10. Biodiversity, Anti-Trypanosomal Activity Screening, and Metabolomic Profiling of Actinomycetes Isolated from Mediterranean Sponges

    PubMed Central

    Cheng, Cheng; MacIntyre, Lynsey; Abdelmohsen, Usama Ramadan; Horn, Hannes; Polymenakou, Paraskevi N.; Edrada-Ebel, RuAngelie; Hentschel, Ute

    2015-01-01

    Marine sponge–associated actinomycetes are considered as promising sources for the discovery of novel biologically active compounds. In the present study, a total of 64 actinomycetes were isolated from 12 different marine sponge species that had been collected offshore the islands of Milos and Crete, Greece, eastern Mediterranean. The isolates were affiliated to 23 genera representing 8 different suborders based on nearly full length 16S rRNA gene sequencing. Four putatively novel species belonging to genera Geodermatophilus, Microlunatus, Rhodococcus and Actinomycetospora were identified based on a 16S rRNA gene sequence similarity of < 98.5% to currently described strains. Eight actinomycete isolates showed bioactivities against Trypanosma brucei brucei TC221 with half maximal inhibitory concentration (IC50) values <20 μg/mL. Thirty four isolates from the Milos collection and 12 isolates from the Crete collection were subjected to metabolomic analysis using high resolution LC-MS and NMR for dereplication purposes. Two isolates belonging to the genera Streptomyces (SBT348) and Micromonospora (SBT687) were prioritized based on their distinct chemistry profiles as well as their anti-trypanosomal activities. These findings demonstrated the feasibility and efficacy of utilizing metabolomics tools to prioritize chemically unique strains from microorganism collections and further highlight sponges as rich source for novel and bioactive actinomycetes. PMID:26407167

  11. Biodiversity, Anti-Trypanosomal Activity Screening, and Metabolomic Profiling of Actinomycetes Isolated from Mediterranean Sponges.

    PubMed

    Cheng, Cheng; MacIntyre, Lynsey; Abdelmohsen, Usama Ramadan; Horn, Hannes; Polymenakou, Paraskevi N; Edrada-Ebel, RuAngelie; Hentschel, Ute

    2015-01-01

    Marine sponge-associated actinomycetes are considered as promising sources for the discovery of novel biologically active compounds. In the present study, a total of 64 actinomycetes were isolated from 12 different marine sponge species that had been collected offshore the islands of Milos and Crete, Greece, eastern Mediterranean. The isolates were affiliated to 23 genera representing 8 different suborders based on nearly full length 16S rRNA gene sequencing. Four putatively novel species belonging to genera Geodermatophilus, Microlunatus, Rhodococcus and Actinomycetospora were identified based on a 16S rRNA gene sequence similarity of < 98.5% to currently described strains. Eight actinomycete isolates showed bioactivities against Trypanosma brucei brucei TC221 with half maximal inhibitory concentration (IC50) values <20 μg/mL. Thirty four isolates from the Milos collection and 12 isolates from the Crete collection were subjected to metabolomic analysis using high resolution LC-MS and NMR for dereplication purposes. Two isolates belonging to the genera Streptomyces (SBT348) and Micromonospora (SBT687) were prioritized based on their distinct chemistry profiles as well as their anti-trypanosomal activities. These findings demonstrated the feasibility and efficacy of utilizing metabolomics tools to prioritize chemically unique strains from microorganism collections and further highlight sponges as rich source for novel and bioactive actinomycetes.

  12. Antimicrobial activities of ozenoxacin against isolates of propionibacteria and staphylococci from Japanese patients with acne vulgaris.

    PubMed

    Nakajima, Akiko; Ikeda, Fumiaki; Kanayama, Shoji; Okamoto, Kazuaki; Matsumoto, Tatsumi; Ishii, Ritsuko; Fujikawa, Akira; Takei, Katsuaki; Kawashima, Makoto

    2016-08-01

    Ozenoxacin, a novel non-fluorinated topical quinolone, was assessed for in vitro antimicrobial activity against clinical isolates of propionibacteria and staphylococci according to the broth microdilution method recommended by the Clinical and Laboratory Standards Institute. The isolates used in this study were collected from Japanese patients with acne vulgaris during a period from 2012 to 2013. The MIC90s of ozenoxacin against Propionibacterium acnes (n=266), Propionibacterium granulosum (n=10), Staphylococcus aureus (n=23), Staphylococcus epidermidis (n=229) and other coagulase-negative staphylococci (n=82) were ≤0.06, ≤0.06, ≤0.06, 0.125 and ≤0.06 µg ml-1, respectively. The antimicrobial activity of ozenoxacin against the clinical isolates of propionibacteria and staphylococci was greater than that of five reference antimicrobial agents which have been used for the treatment of acne vulgaris. The MICs of ozenoxacin were correlated with those of nadifloxacin in P. acnes and S. epidermidis isolates. However, the MICs of ozenoxacin were 0.25-0.5 µg ml-1 and 0.5-8 µg ml-1 against nadifloxacin-resistant P. acnes (MIC: ≥8 µg ml-1; n=8) and S. epidermidis (MIC: ≥64 µg ml-1; n=10), respectively. These results indicated the potent antimicrobial activity against P. acnes and S. epidermidis isolates resistant to nadifloxacin. Topical ozenoxacin could represent an alternative therapeutic drug for acne vulgaris based on its potent antimicrobial activity against the isolates of propionibacteria and staphylococci from acne patients.

  13. Quorum Sensing Inhibiting Activity of Streptomyces coelicoflavus Isolated from Soil

    PubMed Central

    Hassan, Ramadan; Shaaban, Mona I.; Abdel Bar, Fatma M.; El-Mahdy, Areej M.; Shokralla, Shadi

    2016-01-01

    Quorum sensing (QS) systems communicate bacterial population and stimulate microbial pathogenesis through signaling molecules. Inhibition of QS signals potentially suppresses microbial infections. Antimicrobial properties of Streptomyces have been extensively studied, however, less is known about quorum sensing inhibitory (QSI) activities of Streptomyces. This study explored the QSI potential of Streptomyces isolated from soil. Sixty-five bacterial isolates were purified from soil samples with morphological characteristics of Streptomyces. The three isolates: S6, S12, and S17, exhibited QSI effect by screening with the reporter, Chromobacterium violaceum. Isolate S17 was identified as Streptomyces coelicoflavus by sequencing of the hypervariable regions (V1–V6) of 16S rRNA and was assigned gene bank number KJ855087. The QSI effect of the cell-free supernatant of isolate S17 was not abolished by proteinase K indicating the non-enzymatic activity of QSI components of S17. Three major compounds were isolated and identified, using spectroscopic techniques (1D, 2D NMR, and Mass spectrometry), as behenic acid (docosanoic acid), borrelidin, and 1H-pyrrole-2-carboxylic acid. 1H-pyrrole-2-carboxylic acid inhibited QS and related virulence factors of Pseudomonas aeruginosa PAO1 including; elastase, protease, and pyocyanin without affecting Pseudomonas viability. At the molecular level, 1H-pyrrole-2-carboxylic acid suppressed the expression of QS genes (lasI, lasR, lasA, lasB, rhlI, rhlR, pqsA, and pqsR). Moreover, QSI activity of S17 was assessed under different growth conditions and ISP2 medium supplemented with glucose 0.4% w/v and adjusted at pH 7, showed the highest QSI action. In conclusion, 1H-pyrrole-2-carboxylic acid, one of the major metabolites of Streptomyces isolate S17, inhibited QS and virulence determinants of P. aeruginosa PAO1. The findings of the study open the scope to exploit the in vivo efficacy of this active molecule as anti-pathogenic and anti

  14. High-power Faraday isolators based on TAG ceramics.

    PubMed

    Zheleznov, Dmitry; Starobor, Aleksey; Palashov, Oleg; Chen, Chong; Zhou, Shengming

    2014-02-10

    The Faraday isolator based on a new magneto-optical medium--TAG (terbium aluminum garnet) ceramics was implemented and investigated experimentally. The magneto-optical element was temperature-stabilized using water cooling. The device provides a stable isolation ratio of 38 dB at 300 W laser power. Estimates show high performance of the device at a kilowatt laser power.

  15. [Antimicrobial activity of Actinomycetale isolated from the lagoon in Algeria].

    PubMed

    Alliouch-Kerboua, Chérifa; Gacemi Kirane, Djamila; La Scola, Bernard

    2015-01-01

    In the aim of the study of the taxonomy and the antimicrobial activity, a strain of actinomycete SM2/2GF which was isolated from sediment of the lagoon El-Mellah which is situated in the city of El-Kala in the Northeast of Algeria, was tested against diverse pathogenic microorganisms and against a Gram-negative bacterium Pseudomonas alcaliphila which was isolated from water of the lagoon El-Mellah. The phenotypic and the molecular characteristics show that the isolate SM2/2GF belongs to the kind Streptomyces. This strain showed an antimicrobial activity against a Gram-negative bacterium Pseudomonas alcaliphila and the positive-Gram bacteria as Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Bacillus subtilis, Enterococcus faecalis, as well as the yeast Candida albicans. It has no activity against Pseudomonas aeruginosa. The interesting antimicrobial activity of the strain SM2/2GF against the pathogenic microorganisms could encourage further researches on one or several bioactive molecules which it secretes.

  16. Process fault isolation based on transfer entropy algorithm.

    PubMed

    Hajihosseini, Payman; Salahshoor, Karim; Moshiri, Behzad

    2014-03-01

    Complexity of industrial plants and their stringent environmental and safety regulations have necessitated early detection and isolation of process faults. All the existing fault isolation methods can be categorized into two general groups: model-based and data-based. Transfer entropy is a data-based method for measuring propagation direction of disturbance and finding its root cause. In this paper, a new transfer entropy-based method is proposed to isolate different process faults. The novelty of this paper lies in using the transfer entropy idea to generate distinct patterns of information flow among process variables, recognize their correlations in the context of the transferred information in any abnormal condition, and finally isolate different process faults. The experimental results clearly demonstrate the superiority of the proposed method to the conventional methods.

  17. A Quantum Chemical and Statistical Study of Cytotoxic Activity of Compounds Isolated from Curcuma zedoaria

    PubMed Central

    Hamdi, Omer Abdalla Ahmed; Anouar, El Hassane; Shilpi, Jamil A.; Trabolsy, Zuhra Bashir Khalifa Al; Zain, Sharifuddin Bin Md; Zakaria, Nur Shahidatul Shida; Zulkefeli, Mohd; Weber, Jean-Frédéric F.; Malek, Sri Nurestri A.; Rahman, Syarifah Nur Syed Abdul; Awang, Khalijah

    2015-01-01

    A series of 21 compounds isolated from Curcuma zedoaria was subjected to cytotoxicity test against MCF7; Ca Ski; PC3 and HT-29 cancer cell lines; and a normal HUVEC cell line. To rationalize the structure–activity relationships of the isolated compounds; a set of electronic; steric and hydrophobic descriptors were calculated using density functional theory (DFT) method. Statistical analyses were carried out using simple and multiple linear regressions (SLR; MLR); principal component analysis (PCA); and hierarchical cluster analysis (HCA). SLR analyses showed that the cytotoxicity of the isolated compounds against a given cell line depend on certain descriptors; and the corresponding correlation coefficients (R2) vary from 0%–55%. MLR results revealed that the best models can be achieved with a limited number of specific descriptors applicable for compounds having a similar basic skeleton. Based on PCA; HCA and MLR analyses; active compounds were classified into subgroups; which was in agreement with the cell based cytotoxicity assay. PMID:25923077

  18. Phylogenetic diversity and biological activity of culturable Actinobacteria isolated from freshwater fish gut microbiota.

    PubMed

    Jami, Mansooreh; Ghanbari, Mahdi; Kneifel, Wolfgang; Domig, Konrad J

    2015-06-01

    The diversity of Actinobacteria isolated from the gut microbiota of two freshwater fish species namely Schizothorax zarudnyi and Schizocypris altidorsalis was investigated employing classical cultivation techniques, repetitive sequence-based PCR (rep-PCR), partial and full 16S rDNA sequencing followed by phylogenetic analysis. A total of 277 isolates were cultured by applying three different agar media. Based on rep-PCR profile analysis a subset of 33 strains was selected for further phylogenetic investigations, antimicrobial activity testing and diversity analysis of secondary-metabolite biosynthetic genes. The identification based on 16S rRNA gene sequencing revealed that the isolates belong to eight genera distributed among six families. At the family level, 72% of the 277 isolates belong to the family Streptomycetaceae. Among the non-streptomycetes group, the most dominant group could be allocated to the family of Pseudonocardiaceae followed by the members of Micromonosporaceae. Phylogenetic analysis clearly showed that many of the isolates in the genera Streptomyces, Saccharomonospora, Micromonospora, Nocardiopsis, Arthrobacter, Kocuria, Microbacterium and Agromyces formed a single and distinct cluster with the type strains. Notably, there is no report so far about the occurrence of these Actinobacteria in the microbiota of freshwater fish. Of the 33 isolates, all the strains exhibited antibacterial activity against a set of tested human and fish pathogenic bacteria. Then, to study their associated potential capacity to synthesize diverse bioactive natural products, diversity of genes associated with secondary-metabolite biosynthesis including PKS I, PKS II, NRPS, the enzyme PhzE of the phenazine pathways, the enzyme dTGD of 6-deoxyhexoses glycosylation pathway, the enzyme Halo of halogenation pathway and the enzyme CYP in polyene polyketide biosynthesis were investigated among the isolates. All the strains possess at least two types of the investigated

  19. Ornithinimicrobium pekingense sp. nov., isolated from activated sludge.

    PubMed

    Liu, Xing-Yu; Wang, Bao-Jun; Jiang, Cheng-Ying; Liu, Shuang-Jiang

    2008-01-01

    The bacterial strain LW6(T) was isolated from activated sludge of a wastewater treatment bioreactor. Cells of strain LW6(T) are Gram-positive, irregular, short rods and cocci, 0.5-0.8x1.0-1.6 microm. Colonies are light-yellow, smooth, circular and 0.2-1.0 mm in diameter after 3 days incubation. Strain LW6(T) is aerobic and heterotrophic. It grows at a temperature range of 26-38 degrees C and pH range of 6-9, with optimal growth at 33-37 degrees C and pH 7.8-8.2. The predominant cellular fatty acids of strain LW6(T) are iso-C(15:0) (38.9%) and iso-C(17:1)omega9c (18.8%). Strain LW6(T) has the major respiratory menaquinones MK-8(H(4)) and MK-8(H(2)) and polar lipids phosphatidylinositol, phosphatidylglycerol, diphosphatidylglycerol and unknown glycolipid/phospholipids. The cell wall peptidoglycan of strain LW6(T) contained the amino acids ornithine, lysine, glutamic acid, alanine, glycine and aspartic acid. Its molar DNA G+C content is 69 mol% (T(m)). Analysis of 16S rRNA gene sequences indicated that strain LW6(T) was related phylogenetically to members of the genus Ornithinimicrobium, with similarities ranging from 98.3 to 98.7%. The DNA-DNA relatedness of strain LW6(T) to Ornithinimicrobium humiphilum DSM 12362(T) and Ornithinimicrobium kibberense K22-20(T) was respectively 31.5 and 15.2%. Based on these results, it is concluded that strain LW6(T) represents a novel species of the genus Ornithinimicrobium, for which the name Ornithinimicrobium pekingense sp. nov. is proposed. The type strain is strain LW6(T) (=CGMCC 1.5362(T) =JCM 14001(T)).

  20. Chryseomicrobium aureum sp. nov., a bacterium isolated from activated sludge.

    PubMed

    Deng, Shi-Kai; Ye, Xiao-Mei; Chu, Cui-Wei; Jiang, Jin; He, Jian; Zhang, Jun; Li, Shun-Peng

    2014-08-01

    A Gram-stain-positive, rod-shaped, non-motile, non-spore-forming, aerobic bacterial strain, designated BUT-2(T), was isolated from activated sludge of one herbicide-manufacturing wastewater-treatment facility in Kunshan, Jiangsu province, China, and subjected to polyphasic taxonomic studies. Analysis of the 16S rRNA gene sequence indicated that strain BUT-2(T) shared the highest similarity with Chryseomicrobium amylolyticum (98.98%), followed by Chryseomicrobium imtechense (98.88%), with less than 96% similarlity to members of the genera Paenisporosarcina, Planococcus, Sporosarcina and Planomicrobium. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain BUT-2(T) clustered with C. amylolyticum JC16(T) and C. imtechense MW10(T), occupying a distinct phylogenetic position. The major fatty acid (>10% of total fatty acids) type of strain BUT-2(T) was iso-C(15 : 0). The quinone system comprised menaquinone MK-7 (77.8%), MK-6 (11.9%) and MK-8 (10.3%). The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and some unidentified phospholipids. The cell-wall peptidoglycan type of strain BUT-2(T) was L-Orn-D-Glu. The genomic DNA G+C content of strain BUT-2(T) was 48.5 mol%. Furthermore, the DNA-DNA relatedness in hybridization experiments against the reference strain was lower than 70%, confirming that strain BUT-2(T) did not belong to previously described species of the genus Chryseomicrobium. On the basis of its morphological, physiological and chemotaxonomic characteristics as well as phylogenetic analysis, strain BUT-2(T) is considered to represent a novel species of the genus Chryseomicrobium, for which the name Chryseomicrobium aureum sp. nov. is proposed. The type strain is BUT-2(T) ( = CCTCC AB2013082(T) = KACC 17219(T)).

  1. Anti-Quorum Sensing Activity of Substances Isolated from Wild Berry Associated Bacteria

    PubMed Central

    Abudoleh, Suha M.; Mahasneh, Adel M.

    2017-01-01

    Background: Quorum Sensing (QS) is a mechanism used by bacteria to determine their physiological activities and coordinate gene expression based on cell to cell signaling. Many bacterial physiological functions are under the regulation of quorum sensing such as virulence, luminescence, motility, sporulation and biofilm formation. The aim of the present study was to isolate and characterize Quorum Sensing Inhibitory (QSI) substances from epiphytic bacteria residing on wild berries surfaces. Methods: Fifty nine bacterial isolates out of 600 screened bacteria were successfully isolated. These bacteria were obtained from berry surfaces of different plants in the wild forests of Ajloun-Jordan. Screening for QSI activity using Chromobacterium violaceum ATCC 12472 monitor strain, resulted in isolating 6 isolates exhibiting QSI activity only, 11 isolates with QSI and antibacterial activity, and 42 isolates with antibacterial activity only. Three potential isolates S 130, S 153, and S 664, were gram positive rods and spore formers, catalase positive and oxidase negative. These were chosen for further testing and characterization. Results: Different solvent extraction of the QSI substances based on polarity indicated that the activity of S 130 was in the butanol extract, S 153 activity in both chloroform and butanol; and for S 664, the activity was detected in the hexane extract. The chloroform extract of S 153 and hexane extract of S 664 were proteinaceous in nature while QSI substances of the butanol extract of S 130 and S 153 were non-proteinaceous. All the tested QSI substances showed a marked thermal stability when subjected at several time intervals to 70°C, with the highest stability observed for the butanol extract of S 153. Assessing the QSI substances using violacein quantification assay revealed varying degrees of activity depending upon the extracting solvent, type of the producer bacteria and the concentration of the substances. Conclusion: This study

  2. Mode of antibacterial activity of Eclalbasaponin isolated from Eclipta alba.

    PubMed

    Ray, A; Bharali, P; Konwar, B K

    2013-12-01

    The present study was undertaken to evaluate the mode of antibacterial activity of Eclalbasaponin isolated from Eclipta alba, against selected Gram-positive and Gram-negative bacteria. The probable chemical structure was determined by using various spectroscopic techniques such as Fourier transform infrared spectroscopy (FTIR) and mass spectroscopy. The antibacterial activity was evaluated by well diffusion technique, pH sensitivity, chemotaxis, and crystal violet assays. Eclalbasaponin showed clear zone of inhibition against both Bacillus subtilis and Pseudomonas aeruginosa and exhibited growth inhibition at the pH range of 5.5-9.0. The isolated saponin exhibited its positive chemoattractant property for both bacterial strains. Results of crystal violet assay and the presence of UV-sensitive materials in the cell-free supernatant confirmed the cellular damages caused by the treatment of Eclalbasaponin. The release of intracellular proteins due to the membrane damage was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Changes in the cell surface structure and membrane disruption were further revealed by FTIR and scanning electron microscopy analysis. The present study suggests that the isolated saponin from E. alba causes the disruption of the bacterial cell membrane which leads to the loss of bacterial cell viability.

  3. Antimicrobial activities of isothiocyanates against Campylobacter jejuni isolates.

    PubMed

    Dufour, Virginie; Alazzam, Bachar; Ermel, Gwennola; Thepaut, Marion; Rossero, Albert; Tresse, Odile; Baysse, Christine

    2012-01-01

    Food-borne human infection with Campylobacter jejuni is a medical concern in both industrialized and developing countries. Efficient eradication of C. jejuni reservoirs within live animals and processed foods is limited by the development of antimicrobial resistances and by practical problems related to the use of conventional antibiotics in food processes. We have investigated the bacteriostatic and bactericidal activities of two phytochemicals, allyl-isothiocyanate (AITC), and benzyl isothiocyanate (BITC), against 24 C. jejuni isolates from chicken feces, human infections, and contaminated foods, as well as two reference strains NCTC11168 and 81-176. AITC and BITC displayed a potent antibacterial activity against C. jejuni. BITC showed a higher overall antibacterial effect (MIC of 1.25-5 μg mL(-1)) compared to AITC (MIC of 50-200 μg mL(-1)). Both compounds are bactericidal rather than bacteriostatic. The sensitivity levels of C. jejuni isolates against isothiocyanates were neither correlated with the presence of a GGT (γ-Glutamyl Transpeptidase) encoding gene in the genome, with antibiotic resistance nor with the origin of the biological sample. However the ggt mutant of C. jejuni 81-176 displayed a decreased survival rate compared to wild-type when exposed to ITC. This work determined the MIC of two ITC against a panel of C. jejuni isolates, showed that both compounds are bactericidal rather than bacteriostatic, and highlighted the role of GGT enzyme in the survival rate of C. jejuni exposed to ITC.

  4. Graphene plasmons isolator based on non-reciprocal coupling.

    PubMed

    Zhu, Bofeng; Ren, Guobin; Gao, Yixiao; Wu, Beilei; Wang, Qiaoyi; Wan, Chenglong; Jian, Shuisheng

    2015-06-15

    In this paper we propose a graphene plasmons isolator based on non-reciprocal coupling within double graphene layer waveguide structure on a magneto-optical substrate. The difference in modal indices of graphene plasmons in opposite directions enables non-reciprocal coupling, which is theoretically investigated via coupled mode theory (CMT) and shows good agreement with numerical finite elements methods (FEM). The non-reciprocal coupling endows such system functionalities as magnetically controlled "plasmons circulator" or "plasmons isolator". For the latter case, systematical investigations of the insertion losses and isolation ratios with respect to the structural parameters, material properties, environmental parameters, fabrication errors as well as dielectric damping are presented. Theoretical investigation has shown an isolation ratio as 42 dB. The proposed plasmons circulator and isolator may serve as potential building blocks in graphene plasmons circuits.

  5. Screening for antiviral activities of isolated compounds from essential oils.

    PubMed

    Astani, Akram; Reichling, Jürgen; Schnitzler, Paul

    2011-01-01

    Essential oil of star anise as well as phenylpropanoids and sesquiterpenes, for example, trans-anethole, eugenol, β-eudesmol, farnesol, β-caryophyllene and β-caryophyllene oxide, which are present in many essential oils, were examined for their antiviral activity against herpes simplex virus type 1 (HSV-1) in vitro. Antiviral activity was analyzed by plaque reduction assays and mode of antiviral action was determined by addition of the drugs to uninfected cells, to the virus prior to infection or to herpesvirus-infected cells. Star anise oil reduced viral infectivity by >99%, phenylpropanoids inhibited HSV infectivity by about 60-80% and sesquiterpenes suppressed herpes virus infection by 40-98%. Both, star anise essential oil and all isolated compounds exhibited anti-HSV-1 activity by direct inactivation of free virus particles in viral suspension assays. All tested drugs interacted in a dose-dependent manner with herpesvirus particles, thereby inactivating viral infectivity. Star anise oil, rich in trans-anethole, revealed a high selectivity index of 160 against HSV, whereas among the isolated compounds only β-caryophyllene displayed a high selectivity index of 140. The presence of β-caryophyllene in many essential oils might contribute strongly to their antiviral ability. These results indicate that phenylpropanoids and sesquiterpenes present in essential oils contribute to their antiviral activity against HSV.

  6. Numerical simulation of seismic response of a base isolated building with low shear modulus rubber isolators

    SciTech Connect

    Wang, C.Y.

    1993-06-01

    This paper describes seismic-response simulations of a base-isolated building subjected to actual earthquakes using the 3-D computer program, SISEC, developed at Argonne National Laboratory. The isolation system consists of six medium shape factor, high damping, and low shear modulus rubber bearings. To ensure the accuracy of analytical simulation, recorded data of full-size reinforced concrete structures located in Sendai, Japan are used as the benchmarks for comparisons of numerical simulations with observations. Results obtained from both analytical simulations and earthquake observations indicate that the advantage of base isolation in mitigating the acceleration of superstructure is very pronounced. For the two representative earthquakes, one had the strongest ground motion and the other one had similar magnitudes as the rest of the earthquakes recorded at the test site, the simulated accelerations at the roof level of the isolated building are about 20% to 30% of the ordinary building accelerations. Also, results reveal that for both ordinary and base-isolated buildings the computed accelerations agree reasonably well with those recorded.

  7. Numerical simulation of seismic response of a base isolated building with low shear modulus rubber isolators

    SciTech Connect

    Wang, C.Y.

    1993-01-01

    This paper describes seismic-response simulations of a base-isolated building subjected to actual earthquakes using the 3-D computer program, SISEC, developed at Argonne National Laboratory. The isolation system consists of six medium shape factor, high damping, and low shear modulus rubber bearings. To ensure the accuracy of analytical simulation, recorded data of full-size reinforced concrete structures located in Sendai, Japan are used as the benchmarks for comparisons of numerical simulations with observations. Results obtained from both analytical simulations and earthquake observations indicate that the advantage of base isolation in mitigating the acceleration of superstructure is very pronounced. For the two representative earthquakes, one had the strongest ground motion and the other one had similar magnitudes as the rest of the earthquakes recorded at the test site, the simulated accelerations at the roof level of the isolated building are about 20% to 30% of the ordinary building accelerations. Also, results reveal that for both ordinary and base-isolated buildings the computed accelerations agree reasonably well with those recorded.

  8. 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.

  9. Metronidazole activation and isolation of Clostridium acetobutylicum electron transport genes.

    PubMed Central

    Santangelo, J D; Jones, D T; Woods, D R

    1991-01-01

    An Escherichia coli F19 recA, nitrate reductase-deficient mutant was constructed by transposon mutagenesis and shown to be resistant to metronidazole. This mutant was a most suitable host for the isolation of Clostridium acetobutylicum genes on recombinant plasmids, which activated metronidazole and rendered the E. coli F19 strain sensitive to metronidazole. Twenty-five E. coli F19 clones containing different recombinant plasmids were isolated and classified into five groups on the basis of their sensitivity to metronidazole. The clones were tested for nitrate reductase, pyruvate-ferredoxin oxidoreductase, and hydrogenase activities. DNA hybridization and restriction endonuclease mapping revealed that four of the C. acetobutylicum insert DNA fragments on recombinant plasmids were linked in an 11.1-kb chromosomal fragment. DNA sequencing and amino acid homology studies indicated that this DNA fragment contained a flavodoxin gene which encoded a protein of 160 amino acids that activated metronidazole and made the E. coli F19 mutant very sensitive to metronidazole. The flavodoxin and hydrogenase genes which are involved in electron transfer systems were linked on the 11.1-kb DNA fragment from C. acetobutylicum. Images PMID:1991710

  10. Active Thermal Isolation For Hot-Film Anemometers

    NASA Technical Reports Server (NTRS)

    Martinson, Scott D.; Gray, David L.; Carraway, Debra L.

    1993-01-01

    Local heating compensates for conduction of heat from sensors into modules. Two hot-film sensors stacked on wind-tunnel model. Outer sensor detects changes in boundary-layer flow. Inner sensor provides active thermal isolation between outer sensor and model. Thermal boundary condition controlled at response time of detection hot-film sensor, significantly less than response time of internally heated model. Requires less power to maintain outer hot-film sensor at given temperature, enabling system to respond over greater dynamic range before power limits of instrument reached. Stacked sensors bonded to surface of most wind-tunnel models, even to curved surfaces, and removed after completion of experiments.

  11. Antinociceptive activity of discretamine isolated from Duguetia moricandiana.

    PubMed

    Almeida, J R G S; de Lima, J T; de Oliveira, H R; de Oliveira, M R; Meira, P R M; Lúcio, A S S C; Barbosa Filho, J M; Quintans Júnior, L J

    2011-12-01

    The phytochemical study of Duguetia moricandiana Mart. (Annonaceae) yielded the isolation of the alkaloid which was identified by spectral analysis as discretamine. The evaluation of antinociceptive activity carried out by the acetic acid-induced writhing, formalin and hot plate tests in mice, suggests a potent antinociceptive effect. Discretamine (5, 10 and 20 mg kg⁻¹, i.p.) significantly reduced the number of writhes similarly at all doses tested and the number of paw licks during the first phase of formalin test when compared to control. The effect of discretamine on hot plate response provides a confirmation of its central effect. These results indicate antinociceptive properties of this alkaloid.

  12. Seismic base isolation: Elastomer characterization, bearing modeling and system response

    SciTech Connect

    Kulak, R.F.; Wang, C.Y.; Hughes, T.H.

    1991-01-01

    This paper discusses several major aspects of seismic base isolation systems that employ laminated elastomer bearings. Elastomer constitutive models currently being used to represent the nonlinear elastic and hysteretic behavior are discussed. Some aspects of mechanical characterization testing of elastomers is presented along with representative tests results. The development of a finite element based mesh generator for laminated elastomer bearings is presented. Recent advances in the simulation of base isolated structures to earthquake motions are presented along with a sample problem. 13 refs., 19 figs., 1 tab.

  13. Potential role of seismic base isolation in the DOE

    SciTech Connect

    Sommer, S.C.

    1993-08-01

    For nearly two decades, the United States Department of Energy (DOE) has substantially increased its efforts to reduce the effects of earthquakes on its facilities. Traditional means within the DOE for designing or retrofitting structures to mitigate earthquake effects include strengthening and anchoring. A nontraditional and an increasingly popular concept for mitigating the effects of earthquakes on structures is seismic base isolation. Because base isolation is emerging as a promising technology for mitigating seismic effects, its potential role in the DOE must be evaluated. In order to use the technology within the DOE, criteria and guidance need to be developed since base isolation may provide a viable design option for mitigating the effects of earthquakes on DOE facilities. This paper discusses the fundamentals of seismic base isolation, applications of the technology, and how the technology might be applied within the DOE. The future involvement of the DOE in base isolation will be part of its efforts to be a leader in meeting the Federal requirements for seismic safety.

  14. MZI optical isolator with Si-wire waveguides by surface-activated direct bonding.

    PubMed

    Shoji, Yuya; Ito, Masatoshi; Shirato, Yuya; Mizumoto, Tetsuya

    2012-07-30

    We fabricate a Mach-Zehnder interferometer-based optical isolator using a silicon-wire waveguide with magneto-optic garnet cladding using direct bonding techniques. Using Si-wire waveguides, the size of the device is greatly reduced from that of our previous device. We investigate surface-activated direct bonding with nitrogen plasma treatment, which shows better bonding results than oxygen plasma treatment. A large magneto-optic phase shift of 0.8π and an optical isolation of 18 dB are obtained at a wavelength of 1322 nm.

  15. Selective isolation of nitrogen bases from petroleum

    SciTech Connect

    Schmitter, J.M.; Ignatiadis, I.; Arpino, P.; Guiochon, G.

    1983-09-01

    A method has been designed for the rapid separation of nitrogen bases from petroleum by trapping their quaternary ammonium salts on hydrochloric acid treated silica. A chromatographic column filled with this adsorbent and equipped with a solvent recycling system allows a selective and quantitative extraction of basic compounds from large amounts (>100 g) of crude oil. The procedure has been tested with reference compounds, a coker gas-oil, and a heavy biodegraded crude and applied to 15 different oil samples. 22 references, 3 figures, 4 tables.

  16. Biofilm-forming activity of bacteria isolated from toilet bowl biofilms and the bactericidal activity of disinfectants against the isolates.

    PubMed

    Mori, Miho; Gomi, Mitsuhiro; Matsumune, Norihiko; Niizeki, Kazuma; Sakagami, Yoshikazu

    2013-01-01

    To evaluate the sanitary conditions of toilets, the bacterial counts of the toilet bowl biofilms in 5 Kansai area and 11 Kansai and Kanto area homes in Japan were measured in winter and summer seasons, respectively. Isolates (128 strains) were identified by analyzing 16S ribosomal RNA sequences. The number of colonies and bacterial species from biofilms sampled in winter tended to be higher and lower, respectively, than those in summer. Moreover, the composition of bacterial communities in summer and winter samples differed considerably. In summer samples, biofilms in Kansai and Kanto areas were dominated by Blastomonas sp. and Mycobacterium sp., respectively. Methylobacterium sp. was detected in all toilet bowl biofilms except for one sample. Methylobacterium sp. constituted the major presence in biofilms along with Brevundimonas sp., Sphingomonas sp., and/or Pseudomonas sp. The composition ratio of the sum of their genera was 88.0 from 42.9% of the total bacterial flora. The biofilm formation abilities of 128 isolates were investigated, and results suggested that Methylobacterium sp. and Sphingomonas sp. were involved in biofilm formation in toilet bowls. The biofilm formation of a mixed bacteria system that included bacteria with the highest biofilm-forming ability in a winter sample was greater than mixture without such bacteria. This result suggests that isolates possessing a high biofilm-forming activity are involved in the biofilm formation in the actual toilet bowl. A bactericidal test against 25 strains indicated that the bactericidal activities of didecyldimethylammonium chloride (DDAC) tended to be higher than those of polyhexamethylene biguanide (PHMB) and N-benzyl-N,N-dimethyldodecylammonium chloride (ADBAC). In particular, DDAC showed high bactericidal activity against approximately 90% of tested strains under the 5 h treatment.

  17. Antileishmanial Activity of Compounds Isolated from Sassafras albidum.

    PubMed

    Pulivarthi, Divya; Steinberg, Kelly Marie; Monzote, Lianet; Piñón, Abel; Setzer, William N

    2015-07-01

    Leishmaniasis is a neglected tropical disease caused by Leishmania parasitic protozoa, which currently lacks efficient treatment. Natural products have shown promise as a potential source for antiprotozoal drugs. This work focuses on the antileishmanial potential of Sassafras albidum (Lauraceae) bark extract. The crude bark extract of S. albidum showed excellent antileishmanial activity with an IC50 value less than 12.5 μg/mL against promastigotes of L. amazonensis. The chloroform stem bark extract of S. albidum was subjected to preparative column chromatography. Five compounds were isolated, purified by recrystallization, and identified as sesamin, spinescin, β-sitosterol, hexatriacontanal, and 1-triacontanol. Antileishmanial and cytotoxic screening were performed on these compounds. Sesamin exhibited the best activity against L. amazonensis with an IC50 of 15.8 μg/mL and was not cytotoxic to mouse macrophage cells (CC50 > 100 μg/mL).

  18. Antiproliferative activity of xanthones isolated from Artocarpus obtusus.

    PubMed

    Hashim, Najihah Mohd; Rahmani, Mawardi; Ee, Gwendoline Cheng Lian; Sukari, Mohd Aspollah; Yahayu, Maizatulakmal; Oktima, Winda; Ali, Abd Manaf; Go, Rusea

    2012-01-01

    An investigation of the chemical constituents in Artocarpus obtusus species led to the isolation of three new xanthones, pyranocycloartobiloxanthone A (1), dihydroartoindonesianin C (2), and pyranocycloartobiloxanthone B (3). The compounds were subjected to antiproliferative assay against human promyelocytic leukemia (HL60), human chronic myeloid leukemia (K562), and human estrogen receptor (ER+) positive breast cancer (MCF7) cell lines. Pyranocycloartobiloxanthone A (1) consistently showed strong cytotoxic activity against the three cell lines compared to the other two with IC(50) values of 0.5, 2.0 and 5.0 μg/mL, respectively. Compound (1) was also observed to exert antiproliferative activity and apoptotic promoter towards HL60 and MCF7 cell lines at respective IC(50) values. The compound (1) was not toxic towards normal cell lines human nontumorigenic breast cell line (MCF10A) and human peripheral blood mononuclear cells (PBMCs) with IC(50) values of more than 30 μg/mL.

  19. Isolation and anticomplement activity of compounds from Dendropanax morbifera.

    PubMed

    Park, Bo-Young; Min, Byung-Sun; Oh, Sei-Ryang; Kim, Jung-Hee; Kim, Tae-Jin; Kim, Dong-Hee; Bae, Ki-Hwan; Lee, Hyeong-Kyu

    2004-02-01

    Dendropanax morbifera Leveille (Araliaceae) is used in Korea for a variety of disease, such as migraine headache and dysmenorrhea. A new polyacetylene (1) and six known compounds (2-7) were isolated from the leaves of this plant by conventional chromatographic techniques. The structure of the new polyacetylene (1) was determined as (9Z,16S)-16-hydroxy-9,17-octadecadiene-12,14-diynoic acid by spectroscopic means including 2D NMR, which comprised the determination of a chiral by modified Mosher's ester method. Compounds 1-7 were investigated in vitro for their anticomplement activity against the classical pathway of the complement system. Of these, compound 1 showed significant anticomplement activity with 50% inhibitory concentration (IC50) value of 56.98 microM, whereas compounds 2-7 were inactive.

  20. In Search of Alternative Antibiotic Drugs: Quorum-Quenching Activity in Sponges and their Bacterial Isolates

    PubMed Central

    Saurav, Kumar; Bar-Shalom, Rinat; Haber, Markus; Burgsdorf, Ilia; Oliviero, Giorgia; Costantino, Valeria; Morgenstern, David; Steindler, Laura

    2016-01-01

    Owing to the extensive development of drug resistance in pathogens against the available antibiotic arsenal, antimicrobial resistance is now an emerging major threat to public healthcare. Anti-virulence drugs are a new type of therapeutic agent aiming at virulence factors rather than killing the pathogen, thus providing less selective pressure for evolution of resistance. One promising example of this therapeutic concept targets bacterial quorum sensing (QS), because QS controls many virulence factors responsible for bacterial infections. Marine sponges and their associated bacteria are considered a still untapped source for unique chemical leads with a wide range of biological activities. In the present study, we screened extracts of 14 sponge species collected from the Red and Mediterranean Sea for their quorum-quenching (QQ) potential. Half of the species showed QQ activity in at least 2 out of 3 replicates. Six out of the 14 species were selected for bacteria isolation, to test for QQ activity also in isolates, which, once cultured, represent an unlimited source of compounds. We show that ≈20% of the isolates showed QQ activity based on a Chromobacterium violaceum CV026 screen, and that the presence or absence of QQ activity in a sponge extract did not correlate with the abundance of isolates with the same activity from the same sponge species. This can be explained by the unknown source of QQ compounds in sponge-holobionts (host or symbionts), and further by the possible non-symbiotic nature of bacteria isolated from sponges. The potential symbiotic nature of the isolates showing QQ activity was tested according to the distribution and abundance of taxonomically close bacterial Operational Taxonomic Units (OTUs) in a dataset including 97 sponge species and 178 environmental samples (i.e., seawater, freshwater, and marine sediments). Most isolates were found not to be enriched in sponges and may simply have been trapped in the filtration channels of the

  1. In Search of Alternative Antibiotic Drugs: Quorum-Quenching Activity in Sponges and their Bacterial Isolates.

    PubMed

    Saurav, Kumar; Bar-Shalom, Rinat; Haber, Markus; Burgsdorf, Ilia; Oliviero, Giorgia; Costantino, Valeria; Morgenstern, David; Steindler, Laura

    2016-01-01

    Owing to the extensive development of drug resistance in pathogens against the available antibiotic arsenal, antimicrobial resistance is now an emerging major threat to public healthcare. Anti-virulence drugs are a new type of therapeutic agent aiming at virulence factors rather than killing the pathogen, thus providing less selective pressure for evolution of resistance. One promising example of this therapeutic concept targets bacterial quorum sensing (QS), because QS controls many virulence factors responsible for bacterial infections. Marine sponges and their associated bacteria are considered a still untapped source for unique chemical leads with a wide range of biological activities. In the present study, we screened extracts of 14 sponge species collected from the Red and Mediterranean Sea for their quorum-quenching (QQ) potential. Half of the species showed QQ activity in at least 2 out of 3 replicates. Six out of the 14 species were selected for bacteria isolation, to test for QQ activity also in isolates, which, once cultured, represent an unlimited source of compounds. We show that ≈20% of the isolates showed QQ activity based on a Chromobacterium violaceum CV026 screen, and that the presence or absence of QQ activity in a sponge extract did not correlate with the abundance of isolates with the same activity from the same sponge species. This can be explained by the unknown source of QQ compounds in sponge-holobionts (host or symbionts), and further by the possible non-symbiotic nature of bacteria isolated from sponges. The potential symbiotic nature of the isolates showing QQ activity was tested according to the distribution and abundance of taxonomically close bacterial Operational Taxonomic Units (OTUs) in a dataset including 97 sponge species and 178 environmental samples (i.e., seawater, freshwater, and marine sediments). Most isolates were found not to be enriched in sponges and may simply have been trapped in the filtration channels of the

  2. Immunomodulatory activity of polysaccharides isolated from Alchornea cordifolia

    PubMed Central

    Kouakou, Koffi; Schepetkin, Igor A.; Yapi, Ahoua; Kirpotina, Liliya N.; Jutila, Mark A.; Quinn, Mark T.

    2013-01-01

    Ethnopharmacological relevance Extracts of leaves from different species of the genus Alchornea have been used for centuries to treat a variety of medicinal problems in tropical Africa. However, little is known about the high-molecular weight active components conferring therapeutic properties to these extracts. Objective The aim of this study was to evaluate the immunomodulatory activity of polysaccharides isolated from the leaves of Alchornea cordifolia. Materials and methods Water-soluble polysaccharides from leaves of A. cordifolia were extracted and fractionated by DEAE-cellulose, Diaion HP-20, and size-exclusion chromatography. Molecular weight, sugar analysis, and other physical and chemical characterization of the fractions were performed. Immunomodulatory activity of the polysaccharide fractions was evaluated by determining their ability to induce monocyte/macrophage nitric oxide (NO) and cytokine production. Activation of mitogen activated protein kinases (MAPK) was also assessed using a phospho-MAPK array. Activation of nuclear factor κB (NF-κB) was measured using an alkaline phosphatase reporter gene assay in THP1-Blue monocytic cells. Results Six polysaccharide fractions from A. cordifolia were isolated. Fractions containing type II arabinogalactan had potent immunomodulatory activity. Particularly, the parent fraction AP-AU and its high-molecular weight sub-fraction AP-AU1 (average Mr was estimated to be 39.5 kDa) induced production of NO and cytokines [interleukin (IL)-1β, -6, -10, tumor necrosis factor (TNF)-α, and granulocyte macrophage-colony stimulating factor (GM-CSF)] in human peripheral blood mononuclear cells and human and murine monocyte/macrophages cell lines in vitro. Furthermore, treatment with AP-AU1 induced phosphorylation of Akt2, p38δ/p38γ, p70S6K1, RSK2, and mTOR, as well as stimulation of NF-κB transcriptional activity. Conclusion Our results provide a molecular basis to explain a portion of the beneficial therapeutic

  3. Numerical taxonomy of Skermania piniformis and related isolates from activated sludge.

    PubMed

    Sodell, J A; Seviour, R J

    1998-02-01

    The microscopic morphology of nocardioforms causing foaming problems in activated sludge usually consists of filaments with branches at either right angles (Nocardia amarae-Like Organisms, NALO) or acute angles (Pine Tree-Like Organisms, PTLO). Fifty-nine nocardioforms, mainly with PTLO morphology, isolated from mixed liquor and foam samples from Australian activated sludge plants, and 39 reference strains of nocardioforms, including type strains, were characterized using 109 morphological and physiological characters. Cluster analysis and Principal Component Analysis showed that the activated sludge isolates clustered in six groups. All isolates that had typical PTLO morphology clustered unambiguously with the Skermania piniformis type strain (formerly called Nocardia pinensis) showing that, unlike NALO, reliable unequivocal identification of S. piniformis, based on microscopic morphology in activated sludge, was possible. Other foam isolates whose morphology consisted of branches with both acute angles and right angles clustered as two separate groups, probably representing new species. These could not be confused microscopically with S. piniformis, despite some branches showing acute angles. The remaining three groups had typical NALO morphology. One of these groups did not cluster with any reference cultures and may be a new species or genus.

  4. Diarylheptanoids, new phytoestrogens from the rhizomes of Curcuma comosa: Isolation, chemical modification and estrogenic activity evaluation.

    PubMed

    Suksamrarn, Apichart; Ponglikitmongkol, Mathurose; Wongkrajang, Kanjana; Chindaduang, Anon; Kittidanairak, Suthadta; Jankam, Aroon; Yingyongnarongkul, Boon-ek; Kittipanumat, Narin; Chokchaisiri, Ratchanaporn; Khetkam, Pichit; Piyachaturawat, Pawinee

    2008-07-15

    Three new diarylheptanoids, a 1:2 mixture of (3S)- and (3R)-1-(4-methoxyphenyl)-7-phenyl-(6E)-6-hepten-3-ol (13a and 13b) and 1-(4-hydroxyphenyl)-7-phenyl-(6E)-6-hepten-3-one (15), together with two synthetically known diarylheptanoids 1,7-diphenyl-(1E,3E,5E)-1,3,5-triene (9) and 1-(4-hydroxyphenyl)-7-phenyl-(4E,6E)-4,6-heptadien-3-one (16), and nine known diarylheptanoids, 2, 8, 10-12, 14, a 3:1 mixture of 17a and 17b, and 18, were isolated from the rhizomes of Curcuma comosa Roxb. The absolute stereochemistry of the isolated compounds has also been determined using the modified Mosher's method. The isolated compounds and the chemically modified analogues were evaluated for their estrogenic-like transcriptional activity using RT-PCR in HeLa cell line. Some of the isolated diarylheptanoids and their modified analogues exhibited estrogenic activity comparable to or higher than that of the phytoestrogen genistein. Based on the transcriptional activation of both estrogenic targets, Bcl-xL and ERbeta gene expression, the structural features for a diarylheptanoid to exhibit high estrogenic activity are the presence of an olefinic function conjugated with the aromatic ring at the 7-position, a keto group at the 3-position, and a phenolic hydroxyl group at the p-position of the aromatic ring attached to the 1-position of the heptyl chain.

  5. Isolation of skeletal muscle stem cells by fluorescence-activated cell sorting.

    PubMed

    Liu, Ling; Cheung, Tom H; Charville, Gregory W; Rando, Thomas A

    2015-10-01

    The prospective isolation of purified stem cell populations has dramatically altered the field of stem cell biology, and it has been a major focus of research across tissues in different organisms. Muscle stem cells (MuSCs) are now among the most intensely studied stem cell populations in mammalian systems, and the prospective isolation of these cells has allowed cellular and molecular characterizations that were not dreamed of a decade ago. In this protocol, we describe how to isolate MuSCs from limb muscles of adult mice by fluorescence-activated cell sorting (FACS). We provide a detailed description of the physical and enzymatic dissociation of mononucleated cells from limb muscles, a procedure that is essential in order to maximize cell yield. We also describe a FACS-based method that is used subsequently to obtain highly pure populations of either quiescent or activated MuSCs (VCAM(+)CD31(-)CD45(-)Sca1(-)). The isolation process takes ∼5-6 h to complete. The protocol also allows for the isolation of endothelial cells, hematopoietic cells and mesenchymal stem cells from muscle tissue.

  6. Antifouling activity of secondary metabolites isolated from chinese marine organisms.

    PubMed

    Li, Yong-Xin; Wu, Hui-Xian; Xu, Ying; Shao, Chang-Lun; Wang, Chang-Yun; Qian, Pei-Yuan

    2013-10-01

    Biofouling results in tremendous economic losses to maritime industries around the world. A recent global ban on the use of organotin compounds as antifouling agents has further raised demand for safe and effective antifouling compounds. In this study, 49 secondary metabolites, including diterpenoids, steroids, and polyketides, were isolated from soft corals, gorgonians, brown algae, and fungi collected along the coast of China, and their antifouling activity was tested against cyprids of the barnacle Balanus (Amphibalanus) amphitrite. Twenty of the compounds were found to inhibit larval settlement significantly at a concentration of 25 μg ml(-1). Two briarane diterpenoids, juncin O (2) and juncenolide H (3), were the most promising non-toxic antilarval settlement candidates, with EC50 values less than 0.13 μg ml(-1) and a safety ratio (LC50/EC50) higher than 400. A preliminary structure-activity relationships study indicated that both furanon and furan moieties are important for antifouling activity. Intriguingly, the presence of hydroxyls enhanced their antisettlement activity.

  7. Solar and interplanetary activities of isolated and non-isolated coronal mass ejections

    NASA Astrophysics Data System (ADS)

    Bendict Lawrance, M.; Shanmugaraju, A.; Moon, Y.-J.; Umapathy, S.

    2017-02-01

    We report our results on comparison of two halo Coronal Mass Ejections (CME) associated with X-class flares of similar strength (X1.4) but quite different in CME speed and acceleration, similar geo-effectiveness but quite different in Solar Energetic Particle (SEP) intensity. CME1 (non-isolated) was associated with a double event in X-ray flare and it was preceded by another fast halo CME of speed = 2684 km/s (pre-CME) associated with X-ray flare class X5.4 by 1 h from the same location. Since this pre-CME was more eastern, interaction with CME1 and hitting the earth were not possible. This event (CME1) has not suffered the cannibalism since pre-CME has faster speed than post-CME. Pre-CME plays a very important role in increasing the intensity of SEP and Forbush Decrease (FD) by providing energetic seed particles. So, the seed population is the major difference between these two selected events. CME2 (isolated) was a single event. We would like to address on the kinds of physical conditions related to such CMEs and their associated activities. Their associated activities such as, type II bursts, SEP, geomagnetic storm and FD are compared. The following results are obtained from the analysis. (1) The CME leading edge height at the start of metric/DH type II bursts are 2 R⊙/ 4 R⊙ for CME1, but 2 R⊙/ 2.75 R⊙ for CME2. (2) Peak intensity of SEP event associated with the two CMEs are quite different: 6530 pfu for CME1, but 96 pfu for CME2. (3) The Forbush decrease occurred with a minimum decrease of 9.98% in magnitude for CME1, but 6.90% for CME2. (4) These two events produced similar intense geomagnetic storms of intensity of Dst index -130 nT. (5) The maximum southward magnetic fields corresponding to Interplanetary CME (ICME) of these two events are nearly the same, but there is difference in Sheath Bz maximum (-14.2, -6.9 nT). (6) The time-line chart of the associated activities of two CMEs show some difference in the time delay between the onsets of

  8. Antimycobacterial activity in vitro of pigments isolated from Antarctic bacteria.

    PubMed

    Mojib, Nazia; Philpott, Rachel; Huang, Jonathan P; Niederweis, Michael; Bej, Asim K

    2010-11-01

    In this study, we describe the antimycobacterial activity of two pigments, violacein, a purple violet pigment from Janthinobacterium sp. Ant5-2 (J-PVP), and flexirubin, a yellow-orange pigment from Flavobacterium sp. Ant342 (F-YOP). These pigments were isolated from bacterial strains found in the land-locked freshwater lakes of Schirmacher Oasis, East Antarctica. The minimum inhibitory concentrations (MICs) of these pigments for avirulent and virulent mycobacteria were determined by the microplate Alamar Blue Assay (MABA) and Nitrate Reductase Assay (NRA). Results indicated that the MICs of J-PVP and F-YOP were 8.6 and 3.6 μg/ml for avirulent Mycobacterium smegmatis mc²155; 5 and 2.6 μg/ml for avirulent Mycobacterium tuberculosis mc²6230; and 34.4 and 10.8 μg/ml for virulent M. tuberculosis H₃₇Rv, respectively. J-PVP exhibited a ~15 times lower MIC for Mycobacterium sp. than previously reported for violacein pigment from Chromobacterium violaceum, while the antimycobacterial effect of F-YOP remains undocumented. Our results indicate these pigments isolated from Antarctic bacteria might be valuable lead compounds for new antimycobacterial drugs used for chemotherapy of tuberculosis.

  9. Isolation, characterization, and insecticidal activity of an endophyte of drunken horse grass, Achnatherum inebrians.

    PubMed

    Shi, YingWu; Zhang, Xuebing; Lou, Kai

    2013-01-01

    Abstract Endophytic microorganisms reside within plant tissues and have often been found to promote plant growth. In this study, endophytic microorganisms were isolated from the roots, stems, leaves, and seeds of healthy drunken horse grass, Achnatherum inebrians (Hance) Keng (Poales: Poaceae), through the use of a grinding separation method and identified by a dual approach of morphological and physiological observation and 16S rRNA gene-based (for bacteria) and internal transcribed sequence-based (for fungi) molecular identification. The endophytes were then inoculated into liquid media for fermentation, and their crude extracts were employed for insecticidal activity tests using slide disc immersion and nebulization methods. A total of 89 bacteria species, which were classified into eight genera, Bacillus, Pseudomonas, Actinomyces, Corynebacterium, Acinetobacter, Sphingomonas, Paenibacillus, and Phyllobacterium, and two fungi, Claviceps and Chaetomium, were isolated. Of these species, isolates Streptomyces albus (Rossi-Doria) Waksman and Henrici (Actinomycetales: Streptomycetaceae) (GA) and Claviceps purpurea (Fr.) Tul. (Hypocreales: Clavicipitaceae) (PF-2) were shown to produce mortality rates of more than 90% in the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), after first and second screenings. The isolates PF-2 and GA associated with A. inebrians had significant insecticidal activities towards A. gossypii Glover (Hemiptera: Aphididae) and may provide a new biological resource for exploring a new microbial insecticide.

  10. Isolation, Characterization, and Insecticidal Activity of an Endophyte of Drunken Horse Grass, Achnatherum inebrians

    PubMed Central

    Shi, YingWu; Zhang, Xuebing; Lou, Kai

    2013-01-01

    Endophytic microorganisms reside within plant tissues and have often been found to promote plant growth. In this study, endophytic microorganisms were isolated from the roots, stems, leaves, and seeds of healthy drunken horse grass, Achnatherum inebrians (Hance) Keng (Poales: Poaceae), through the use of a grinding separation method and identified by a dual approach of morphological and physiological observation and 16S rRNA gene-based (for bacteria) and internal transcribed sequence-based (for fungi) molecular identification. The endophytes were then inoculated into liquid media for fermentation, and their crude extracts were employed for insecticidal activity tests using slide disc immersion and nebulization methods. A total of 89 bacteria species, which were classified into eight genera, Bacillus, Pseudomonas, Actinomyces, Corynebacterium, Acinetobacter, Sphingomonas, Paenibacillus, and Phyllobacterium, and two fungi, Claviceps and Chaetomium, were isolated. Of these species, isolates Streptomyces albus (Rossi-Doria) Waksman and Henrici (Actinomycetales: Streptomycetaceae) (GA) and Claviceps purpurea (Fr.) Tul. (Hypocreales: Clavicipitaceae) (PF-2) were shown to produce mortality rates of more than 90% in the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), after first and second screenings. The isolates PF-2 and GA associated with A. inebrians had significant insecticidal activities towards A. gossypii Glover (Hemiptera: Aphididae) and may provide a new biological resource for exploring a new microbial insecticide. PMID:24784492

  11. Active pneumatic vibration isolation system using negative stiffness structures for a vehicle seat

    NASA Astrophysics Data System (ADS)

    Danh, Le Thanh; Ahn, Kyoung Kwan

    2014-02-01

    In this paper, an active pneumatic vibration isolation system using negative stiffness structures (NSS) for a vehicle seat in low excitation frequencies is proposed, which is named as an active system with NSS. Here, the negative stiffness structures (NSS) are used to minimize the vibratory attraction of a vehicle seat. Owing to the time-varying and nonlinear behavior of the proposed system, it is not easy to build an accurate dynamic for model-based controller design. Thus, an adaptive intelligent backstepping controller (AIBC) is designed to manage the system operation for high-isolation effectiveness. In addition, an auxiliary control effort is also introduced to eliminate the effect of the unpredictable perturbations. Moreover, a radial basis function neural network (RBFNN) model is utilized to estimate the optimal gain of the auxiliary control effort. Final control input and the adaptive law for updating coefficients of the approximate series can be obtained step by step using a suitable Lyapunov function. Afterward, the isolation performance of the proposed system is assessed experimentally. In addition, the effectiveness of the designed controller for the proposed system is also compared with that of the traditional backstepping controller (BC). The experimental results show that the isolation effectiveness of the proposed system is better than that of the active system without NSS. Furthermore, the undesirable chattering phenomenon in control effort is quite reduced by the estimation mechanism. Finally, some concluding remarks are given at the end of the paper.

  12. Anticancer activity of flavane gallates isolated from Plicosepalus curviflorus

    PubMed Central

    Fawzy, Ghada Ahmed; Al-Taweel, Areej Mohammad; Perveen, Shagufta

    2014-01-01

    Background: Previous investigation of the methanol extract of Plicosepalus curviflorus leaves led to the isolation of two new flavane gallates (1, 2), together with other compounds including quercetin (3). The stems of P. curviflorus are used traditionally for the treatment of cancer in Yemen. Objective: The aim of this study was to evaluate the anticancer activity of the plant methanol extract as well as isolated compounds (1-3). Materials and Methods: The human cancer cell lines used were; MCF-7, HepG-2, HCT-116, Hep-2, HeLa and normal, Vero cell line using the Crystal Violet Staining method (CVS). Results: Quercetin (3) possessed the highest anticancer effect against all five cell lines (IC50 ranging from 3.6 to 16.2 μg/ml). It was followed by 2S, 3R-3, 3′, 4′, 5, 7-pentahydroxyflavane-5-O-gallate (1), with IC50 ranging from 11.6 to 38.8 μg/ml. The weakest anticancer activity was given by 2S, 3R-3,3′,4′,5,5′,7-hexahydroxyflavane-3′,5-di-O-gallate (2) with IC50 ranging from 39.8 to above 50 μg/ml, compared to vinblastine sulphate as reference drug. Colon, liver and breast cell lines seemed to be more sensitive to the tested compounds than the cervical and laryngeal cell lines. Concerning the cytotoxic effect on Vero cell line, the pentahydroxyflavane-5-O-gallate (1) showed the highest IC50 ( 138.2 μg/ml), while quercetin exhibited the lowest IC50 to Vero cells (30.5 μg/ml), compared to vinblastine sulphate as reference drug (IC50: 39.7 μg/ml). Conclusion: The results suggest the possible use of compounds 1 and 3 as anticancer drugs especially against colon and liver cancers. PMID:25298669

  13. Immunostimulating activity of polyhydric alcohol isolated from Taxus cuspidata.

    PubMed

    Lee, Choon Guen; Lee, Jisun; Lee, Da Gyung; Kim, Joo Won; Alnaeeli, Mawadda; Park, Yong Il; Park, Jae Kweon

    2016-04-01

    A polyhydric alcohol (PAL) was isolated from Taxus cuspidata and its immunostimulatory activities were assessed. The primary monosaccharide composition of the PAL was determined to be glucose, where HPAEC analysis showed no significant amount of any other sugars. However, glycerol and xylitol were identified as the main sugar alcohols. Fourier-transform infrared (FT-IR) analysis indicated that the purified PAL is a complex glycitol, which structurally contains significant amount of hydroxyl groups. MALDI-TOF mass spectroscopy also demonstrated that PAL is a complex glycitol built in hexose polymerization. Enzyme linked immunosorbent assay showed that the PAL stimulates the release of the proinflammatory cytokines TNF-α and IL-6 in a dose-dependent manner. Furthermore, treatment of RAW 264.7 cells with PAL for 24h remarkably increased the phosphorylation levels of ERK, p38 and JNK in a dose-dependent manner, whereas the total protein levels of ERK (t-ERK), p38 (t-p38) and JNK (t-JNK) remained unchanged. These results clearly demonstrate that PAL stimulates the immune response in RAW 264.7 cells through the activation of MAPKs (ERK, p38 and JNK) signaling pathway. To the best of our knowledge, this is the first study to demonstrate the primary structure and immune-stimulating activities of PAL from the fruit of T. cuspidata.

  14. Complement activation of electrogenic ion transport in isolated rat colon.

    PubMed

    McCole, D F; Otti, B; Newsholme, P; Baird, A W

    1997-11-15

    The complement cascade is an important component in many immune and inflammatory reactions and may contribute to both the diarrhoea and inflammation associated with inflammatory bowel disease. Isolated rat colonic mucosae were voltage clamped in Ussing chambers. Basolateral addition of zymosan-activated whole human serum (ZAS) induced a rapid onset, transient inward short circuit current (SCC). This response was concentration dependent and was significantly attenuated by pre-heating ZAS at 60 degrees C for 30 min. Depletion of complement from normal human serum with cobra venom factor (CVF) significantly lowered SCC responses. Chloride was the primary charge carrying ion as responses to ZAS were abolished in the presence of the loop diuretic bumetanide. The complement component C3a stimulated ion transport but not to the same extent as whole serum. Exogenous C5 was without effect. The cyclooxygenase inhibitor piroxicam significantly attenuated the response to ZAS. These findings support the possibility that complement activation may contribute to the pathophysiology of secretory diarrhoea since activation of electrogenic chloride secretion converts intestinal epithelia to a state of net fluid secretion.

  15. Carbonic anhydrase activity in isolated chloroplasts of chlamydomonas reinhardtii

    SciTech Connect

    Katzman, G.; Togasaki, R.K. ); Marcus, Y. ); Moroney, J.V. )

    1989-04-01

    In a new assay of carbonic anhydrase, NaH{sup 14}CO{sub 3} solution at the bottom of a sealed vessel releases {sup 14}CO{sub 3} which diffuses to the top of the vessel to be assimilated by actively photosynthesizing Chlamydomonas cells. The assay is initiated by illuminating cells and stopped by turning the light off and killing the cells with acid. Enzyme activity was estimated from acid stable radioactivity above the uncatalyzed background level. With bovine carbonic anhydrase, 1.5 Wilbur Anderson Unit (WAU) can be consistantly measured at 5-6 fold above background. Sonicated whole cells of air adapted wild type (+)gave 741.1 {plus minus} 12.4 WAU/mg chl. Intact washed cells of mixotrophically grown wall-less mutant CWD(-) and a high CO2 requiring wall-less double mutant CIA-3/CW15 (-) gave 7.1 {plus minus} 1.9 and 2.8 {plus minus} 7.8 WAU/mg chl respectively. Chloroplasts isolated from CWD and CIA-3/CW15 and subsequently disrupted gave 64.0 {plus minus} 14.7 and 2.8 {plus minus} 3.2 WAU/mg chl respectively. Chloroplast sonicate from another wall-less mutant CW15(-) gave activity comparable to CWD. Thus on a chlorophyll basis, enzyme activity in chloroplasts from mixotrophically grown cells is about 1/10th of the level found in air adapted wild type cells. CIA-3 seems to lack this activity.

  16. Microplate-based high throughput screening procedure for the isolation of lipid-rich marine microalgae

    PubMed Central

    2011-01-01

    We describe a new selection method based on BODIPY (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene) staining, fluorescence activated cell sorting (FACS) and microplate-based isolation of lipid-rich microalgae from an environmental sample. Our results show that direct sorting onto solid medium upon FACS can save about 3 weeks during the scale-up process as compared with the growth of the same cultures in liquid medium. This approach enabled us to isolate a biodiverse collection of several axenic and unialgal cultures of different phyla. PMID:22192119

  17. Recorded seismic response of a base-isolated steel bridge carrying a steel water pipe

    USGS Publications Warehouse

    Safak, E.; Brady, A.G.

    1989-01-01

    A set of strong motion records was obtained from the base-isolated Santa Ana River Pipeline Bridge during the magnitude 5.9 Whittier Narrows, California, earthquake of October 1, 1987. The analysis of the records show that the level of excitation was not strong enough to fully activate the base isolators. The dominant modes of the response are the translations of the abutment-bridge-pipe system in the longitudinal and transverse directions, and the bending of the steel truss between supports in the vertical direction.

  18. Assessment of antifungal activity of herbal and conventional toothpastes against clinical isolates of Candida albicans

    PubMed Central

    Adwan, Ghaleb; Salameh, Yousef; Adwan, Kamel; Barakat, Ali

    2012-01-01

    Objective To detect the anticandidal activity of nine toothpastes containing sodium fluoride, sodium monofluorophosphate and herbal extracts as an active ingredients against 45 oral and non oral Candida albicans (C. albicans) isolates. Methods The antifungal activity of these toothpaste formulations was determined using a standard agar well diffusion method. Statistical analysis was performed using a statistical package, SPSS windows version 15, by applying mean values using one-way ANOVA with post-hoc least square differences (LSD) method. A P value of less than 0.05 was considered significant. Results All toothpastes studied in our experiments were effective in inhibiting the growth of all C. albicans isolates. The highest anticandidal activity was obtained from toothpaste that containing both herbal extracts and sodium fluoride as active ingredients, while the lowest activity was obtained from toothpaste containing sodium monofluorophosphate as an active ingredient. Antifungal activity of Parodontax toothpaste showed a significant difference (P< 0.001) against C. albicans isolates compared to toothpastes containing sodium fluoride or herbal products. Conclusions In the present study, it has been demonstrated that toothpaste containing both herbal extracts and sodium fluoride as active ingredients are more effective in control of C. albicans, while toothpaste that containing monofluorophosphate as an active ingredient is less effective against C. albicans. Some herbal toothpaste formulations studied in our experiments, appear to be equally effective as the fluoride dental formulations and it can be used as an alternative to conventional formulations for individuals who have an interest in naturally-based products. Our results may provide invaluable information for dental professionals. PMID:23569933

  19. DNA Microarray-Based Typing of Streptococcus agalactiae Isolates

    PubMed Central

    Nitschke, Heike; Slickers, Peter; Müller, Elke; Ehricht, Ralf

    2014-01-01

    Streptococcus agalactiae frequently colonizes the urogenital tract, and it is a major cause of bacterial septicemia, meningitis, and pneumonia in newborns. For typing purposes, a microarray targeting group B streptococcus (GBS) virulence-associated markers and resistance genes was designed and validated with reference strains, as well as clinical and veterinary isolates. Selected isolates were also subjected to multilocus sequence typing. It was observed that putative typing markers, such as alleles of the alpha-like protein or capsule types, vary independently of each other, and they also vary independently from the affiliation to their multilocus sequence typing (MLST)-defined sequence types. Thus, it is not possible to assign isolates to sequence types based on the identification of a single distinct marker, such as a capsule type or alp allele. This suggests the occurrence of frequent genomic recombination. For array-based typing, a set of 11 markers (bac, alp, pil1 locus, pepS8, fbsB, capsule locus, hylB, abiG-I/-II plus Q8DZ34, pil2 locus, nss plus srr plus rogB2, and rgfC/A/D/B) was defined that provides a framework for splitting the tested 448 S. agalactiae isolates into 76 strains that clustered mainly according to MLST-defined clonal complexes. There was evidence for region- and host-specific differences in the population structure of S. agalactiae, as well as an overrepresentation of strains related to sequence type 17 among the invasive isolates. The arrays and typing scheme described here proved to be a convenient tool for genotyping large numbers of clinical/veterinary isolates and thus might help obtain insight into the epidemiology of S. agalactiae. PMID:25165085

  20. Highly effective bacterial agents against Cimbex quadrimaculatus (Hymenoptera: Cimbicidae): isolation of bacteria and their insecticidal activities.

    PubMed

    Cakici, Filiz Ozkan; Ozgen, İnanc; Bolu, Halil; Erbas, Zeynep; Demirbağ, Zihni; Demir, İsmail

    2015-01-01

    Cimbex quadrimaculatus (Hymenoptera: Cimbicidae) is one of the serious pests of almonds in Turkey and worldwide. Since there is no effective control application against this pest, it has been a serious problem up to now. Therefore, we aimed to find an effective bacterium that can be utilized as a biocontrol agent against C. quadrimaculatus in pest management. We isolated seven bacteria from dead and live C. quadrimaculatus larvae, and evaluated the larvicidal potency of all isolates on the respective pest. Based on the morphological, physiological, biochemical and molecular properties (partial sequence of 16S rRNA gene), the isolates were identified to be Bacillus safensis (CQ1), Bacillus subtilis (CQ2), Bacillus tequilensis (CQ3), Enterobacter sp. (CQ4), Kurthia gibsonii (CQ5), Staphylococcus sp. (CQ6) and Staphylococcus sciuri (CQ7). The results of the larvicidal activities of these isolates indicated that the mortality value obtained from all treatments changed from 58 to 100 %, and reached 100 % with B. safensis (CQ1) and B. subtilis (CQ2) on the 3rd instar larvae within 10 days of application of 1.89 × 10(9) cfu/mL bacterial concentration at 25 °C under laboratory conditions. Findings from this study indicate that these isolates appear to be a promising biocontrol agent for C. quadrimaculatus.

  1. The Contribution of Antibiotic Resistance Mechanisms in Clinical Burkholderia cepacia Complex Isolates: An Emphasis on Efflux Pump Activity

    PubMed Central

    Tseng, Sung-Pin; Tsai, Wan-Chi; Liang, Chih-Yuan; Lin, Yin-Shiou; Huang, Jun-Wei; Chang, Chung-Yu; Tyan, Yu-Chang; Lu, Po-Liang

    2014-01-01

    Due to the limited information of the contribution of various antibiotic resistance mechanisms in clinical Burkholderia cepacia complex isolates, Antibiotic resistance mechanisms, including integron analysis, identification of quinolone resistance-determining region mutations, measurement of efflux pump activity, and sequence analysis of efflux pump regulators, were investigated in 66 clinical B. cepacia complex isolates. Species were identified via recA-RFLP and MALDI-TOF. Four genomovars were identified by recA-RFLP. B. cenocepacia (genomovar III) was the most prevalent genomovar (90.1%). Most isolates (60/66, 90.9%) were correctly identified by MALDI-TOF analysis. Clonal relatedness determined by PFGE analysis revealed 30 pulsotypes, including two major pulsotypes that comprised 22.7% and 18.2% of the isolates, respectively. Seventeen (25.8%) isolates harboured class 1 integron with various combinations of resistance genes. Among six levofloxacin-resistant isolates, five had single-base substitutions in the gyrA gene and three demonstrated efflux pump activities. Among the 42 isolates exhibiting resistance to at least one antimicrobial agent, 94.4% ceftazidime-resistant isolates (17/18) and 72.7% chloramphenicol-resistant isolates (16/22) demonstrated efflux pump activity. Quantitation of efflux pump RNA level and sequence analysis revealed that over-expression of the RND-3 efflux pump was attributable to specific mutations in the RND-3 efflux pump regulator gene. In conclusion, high-level expression of efflux pumps is prevalent in B. cepacia complex isolates. Mutations in the RND-3 efflux pump regulator gene are the major cause of efflux pump activity, resulting in the resistance to antibiotics in clinical B. cepacia complex isolates. PMID:25153194

  2. The contribution of antibiotic resistance mechanisms in clinical Burkholderia cepacia complex isolates: an emphasis on efflux pump activity.

    PubMed

    Tseng, Sung-Pin; Tsai, Wan-Chi; Liang, Chih-Yuan; Lin, Yin-Shiou; Huang, Jun-Wei; Chang, Chung-Yu; Tyan, Yu-Chang; Lu, Po-Liang

    2014-01-01

    Due to the limited information of the contribution of various antibiotic resistance mechanisms in clinical Burkholderia cepacia complex isolates, Antibiotic resistance mechanisms, including integron analysis, identification of quinolone resistance-determining region mutations, measurement of efflux pump activity, and sequence analysis of efflux pump regulators, were investigated in 66 clinical B. cepacia complex isolates. Species were identified via recA-RFLP and MALDI-TOF. Four genomovars were identified by recA-RFLP. B. cenocepacia (genomovar III) was the most prevalent genomovar (90.1%). Most isolates (60/66, 90.9%) were correctly identified by MALDI-TOF analysis. Clonal relatedness determined by PFGE analysis revealed 30 pulsotypes, including two major pulsotypes that comprised 22.7% and 18.2% of the isolates, respectively. Seventeen (25.8%) isolates harboured class 1 integron with various combinations of resistance genes. Among six levofloxacin-resistant isolates, five had single-base substitutions in the gyrA gene and three demonstrated efflux pump activities. Among the 42 isolates exhibiting resistance to at least one antimicrobial agent, 94.4% ceftazidime-resistant isolates (17/18) and 72.7% chloramphenicol-resistant isolates (16/22) demonstrated efflux pump activity. Quantitation of efflux pump RNA level and sequence analysis revealed that over-expression of the RND-3 efflux pump was attributable to specific mutations in the RND-3 efflux pump regulator gene. In conclusion, high-level expression of efflux pumps is prevalent in B. cepacia complex isolates. Mutations in the RND-3 efflux pump regulator gene are the major cause of efflux pump activity, resulting in the resistance to antibiotics in clinical B. cepacia complex isolates.

  3. Isolation, antimicrobial activities, and primary structures of hamster neutrophil defensins.

    PubMed Central

    Mak, P; Wójcik, K; Thogersen, I B; Dubin, A

    1996-01-01

    Hamster (Mesocricetus auratus) neutrophil granules contain at least four microbicidal peptides belonging to the defensin family. These compounds were purified from granule acid extracts by reverse-phase chromatography and termed HaNP-1 to -4 (hamster neutrophil peptide). HaNP-1 and HaNP-3 revealed the most bactericidal activity, with a 50% inhibitory concentration of 0.3 to 0.8 microg/ml for Staphylococcus aureus and Streptococcus pyogenes strains. The HaNP-4 was always isolated in concentrations exceeding about 10 times the concentrations of other hamster peptides, but its antibacterial activity as well as that of HaNP-2 was relatively lower, probably as a result of conserved Arg residue substitutions. Other microorganisms were also tested, and generally, hamster defensins exhibited less potency against gram-negative bacteria. The amino acid sequence of hamster defensins showed a high percentage of identity to the sequence of mouse enteric defensins, reaching about 60% identical residues in the case of HaNP-3 and cryptdin 3. PMID:8890190

  4. Analysing human neural stem cell ontogeny by consecutive isolation of Notch active neural progenitors.

    PubMed

    Edri, Reuven; Yaffe, Yakey; Ziller, Michael J; Mutukula, Naresh; Volkman, Rotem; David, Eyal; Jacob-Hirsch, Jasmine; Malcov, Hagar; Levy, Carmit; Rechavi, Gideon; Gat-Viks, Irit; Meissner, Alexander; Elkabetz, Yechiel

    2015-03-23

    Decoding heterogeneity of pluripotent stem cell (PSC)-derived neural progeny is fundamental for revealing the origin of diverse progenitors, for defining their lineages, and for identifying fate determinants driving transition through distinct potencies. Here we have prospectively isolated consecutively appearing PSC-derived primary progenitors based on their Notch activation state. We first isolate early neuroepithelial cells and show their broad Notch-dependent developmental and proliferative potential. Neuroepithelial cells further yield successive Notch-dependent functional primary progenitors, from early and midneurogenic radial glia and their derived basal progenitors, to gliogenic radial glia and adult-like neural progenitors, together recapitulating hallmarks of neural stem cell (NSC) ontogeny. Gene expression profiling reveals dynamic stage-specific transcriptional patterns that may link development of distinct progenitor identities through Notch activation. Our observations provide a platform for characterization and manipulation of distinct progenitor cell types amenable for developing streamlined neural lineage specification paradigms for modelling development in health and disease.

  5. Isolation, structure elucidation and biological activity of angucycline antibiotics from an epiphytic yew streptomycete.

    PubMed

    Maruna, Michal; Sturdikova, Maria; Liptaj, Tibor; Godany, Andrej; Muckova, Marta; Certik, Milan; Pronayova, Nadezda; Proksa, Bohumil

    2010-04-01

    In the course of study of epiphytic microorganisms occurring on the surface of roots of Taxus baccata L. a new strain Streptomyces sp. AC113 was isolated. According to 16S ribosomal DNA-based identification the new strain is 99% identical with Streptomyces flavidofuscus. This strain cultivated in an arginine glycerol medium produced three major metabolites identified as (-)-8-O -methyltetrangomycin (1), 8-O -methyltetrangulol (2) and 8-O -methyl-7-deoxo-7-hydroxytetrangomycin (3). The chemical structures of these angucyclines were elucidated by 1D and 2D NMR as well as by mass spectrometry. Isolated angucycline metabolites showed significant antimicrobial activity against Bacillus cereus and Listeria mocytogenes. Cytotoxic activities of compounds 1, 2 and 3 against four cell lines (B16, HT-29 and non - tumor V79, L929) were evaluated. Compound 3 was the most potent anticancer agents with IC(50) 0.054 microg/ml against cell line B16.

  6. Microgravity Vibration Isolation System Based on Parallel Kinematic Communications

    NASA Astrophysics Data System (ADS)

    Russkin, Alexander; Postojuk, Nikolay

    The paper is devoted to the construction of an active vibration isolation system of experimental and technological equipment operating in microgravity conditions. Space experiments associated with obtaining ultrapure materials are required the residual level of microgravity vibration from mmug to mg at the frequency range from 0.01 Hz to 100 Hz in the experiment area. This residual level of microgravity vibration is difficult to achieve by conventional passive protection systems. To date the different types of active vibration isolation systems are constructed, such as STABLE, ARIS, MIM, g-LIMIT and MVIS, but their characteristics and geometrical parameters do not always satisfy the given technological requirements. In this paper, the mechanism with parallel kinematic constraints (MPKS) is proposed for constructing microgravity active vibration isolation system, which provides protection against vibrations in six degrees of freedom and can be scaled depending on the specific tasks. MPKS distinguishing feature is the presence of closed kinematic chain, which provide high rigidity of the structure, reduce the mass of moving parts and reduce the load on the actuator. As a result, this increases the dynamics and positioning accuracy MPKS. The proposed version of microgravity vibration isolation system consists of two main parts: the electromechanical assembly and control unit. The main specifications for the constituent parts of the system are defined. A comparative analysis of different types of actuators and sensors for electromechanical assembly is carried out. The appropriate components to provide the desired specifications are selected. There are proposed to use piezoelectric motors as actuators in electromechanical assembly. Mathematical models of MPKS with six degrees of freedom and control system are considered. The structure of the control system and controller type is selected. A mathematical model of proposed microgravity vibration isolation system is

  7. Quorum Sensing Activity of Aeromonas Caviae Strain YL12, A Bacterium Isolated from Compost

    PubMed Central

    Lim, Yan-Lue; Ee, Robson; Yin, Wai-Fong; Chan, Kok-Gan

    2014-01-01

    Quorum sensing is a well-studied cell-to-cell communication method that involves a cell-density dependent regulation of genes expression mediated by signalling molecules. In this study, a bacterium isolated from a plant material compost pile was found to possess quorum sensing activity based on bioassay screening. Isolate YL12 was identified using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry and molecular typing using rpoD gene which identified the isolate as Aeromonas caviae. High resolution tandem mass spectrometry was subsequently employed to identify the N-acyl homoserine lactone profile of Aeromonas caviae YL12 and confirmed that this isolate produced two short chain N-acyl homoserine lactones, namely C4-HSL and C6, and the production was observed to be cell density-dependent. Using the thin layer chromatography (TLC) bioassay, both AHLs were found to activate C. violaceum CV026, whereas only C6-HSL was revealed to induce bioluminescence expression of E. coli [pSB401]. The data presented in this study will be the leading steps in understanding the role of quorum sensing in Aeromonas caviae strain YL12. PMID:24759107

  8. Biological activities from extracts of endophytic fungi isolated from Viguiera arenaria and Tithonia diversifolia.

    PubMed

    Guimarães, Denise O; Borges, Warley S; Kawano, Cristina Y; Ribeiro, Patrícia H; Goldman, Gustavo H; Nomizo, Auro; Thiemann, Otávio H; Oliva, Glaucius; Lopes, Norberto P; Pupo, Mônica T

    2008-01-01

    A total of 39 endophytic fungi have been isolated from Viguiera arenaria and Tithonia diversifolia, both collected in São Paulo State, Brazil. The isolates were identified based on their ribosomal DNA sequences. The ethyl acetate (EtOAc) extracts of all endophytic fungi were evaluated for their antimicrobial, antiparasitic and antitumoral activity. Antimicrobial screening was conducted using an agar diffusion assay against three pathogenic microorganisms: Staphylococcus aureus, Escherichia coli and Candida albicans. Antiparasitic activity was determined by enzymatic inhibition of gGAPDH of Trypanosoma cruzi and adenine phosphorybosiltransferase (APRT) of Leishmania tarentolae. Antitumoral activity was tested against human T leukemia cells by the Mosmann colorimetric method. All extracts showed activity in at least one assay: 79.5% of the extracts were cytotoxic against leukemia cells, 5.1% of the extracts were active against S. aureus, 25.6% against E. coli and 64.1% against Candida albicans. Only one extract showed promising results in the inhibition of parasitic enzymes gGAPDH (95.0%) and three were found to inhibit APRT activity. The cytotoxic extract produced by the strain VA1 (Glomerella cingulata) was fractionated and yielded nectriapyrone and tyrosol. Nectriapyrone showed relevant cytotoxic activity against both human T leukemia and melanoma tumor cell lines.

  9. Isolation, screening, and molecular characterization of plant growth promoting rhizobacteria isolates of Azotobacter and Trichoderma and their beneficial activities

    PubMed Central

    Kasa, Parameswari; Modugapalem, Hemalatha; Battini, Kishori

    2015-01-01

    Objectives: The present study was conducted for isolation, screening, and identification of Azotobacter and Trichoderma from different soil samples. Methods: A total of 10 isolates of Azotobacter and Trichoderma were isolated from rhizospheric soils. The test isolates were biochemically characterized and screened in in-vitro conditions for their plant growth promoting properties. DNA polymorphism of isolates was studied using randomly amplified polymorphic DNA analysis. Results: A total of 41 bands were scored, out of which 35 bands were found to be 85.59% polymorphic in Azotobacter and in Trichoderma among total 37 bands scored of which 29 were found to be 78.37% polymorphic. The influence of isolated plant growth promoting rhizobacteria (PGPR) strains on plant growth was studied using different parameters such as height of the plant, number of leaves, and number of branches, and bio-control activity was studied. Conclusion: The present results concluded that the multiple beneficial activities of PGPR traits increase the plant growth and bio-control activity. PMID:26283830

  10. Technology transfer package on seismic base isolation - Volume I

    SciTech Connect

    1995-02-14

    This Technology Transfer Package provides some detailed information for the U.S. Department of Energy (DOE) and its contractors about seismic base isolation. Intended users of this three-volume package are DOE Design and Safety Engineers as well as DOE Facility Managers who are responsible for reducing the effects of natural phenomena hazards (NPH), specifically earthquakes, on their facilities. The package was developed as part of DOE's efforts to study and implement techniques for protecting lives and property from the effects of natural phenomena and to support the International Decade for Natural Disaster Reduction. Volume I contains the proceedings of the Workshop on Seismic Base Isolation for Department of Energy Facilities held in Marina Del Rey, California, May 13-15, 1992.

  11. Technology transfer package on seismic base isolation - Volume II

    SciTech Connect

    1995-02-14

    This Technology Transfer Package provides some detailed information for the U.S. Department of Energy (DOE) and its contractors about seismic base isolation. Intended users of this three-volume package are DOE Design and Safety Engineers as well as DOE Facility Managers who are responsible for reducing the effects of natural phenomena hazards (NPH), specifically earthquakes, on their facilities. The package was developed as part of DOE's efforts to study and implement techniques for protecting lives and property from the effects of natural phenomena and to support the International Decade for Natural Disaster Reduction. Volume II contains the proceedings for the Short Course on Seismic Base Isolation held in Berkeley, California, August 10-14, 1992.

  12. Qualitative Event-Based Fault Isolation under Uncertain Observations

    DTIC Science & Technology

    2014-10-02

    systems , automatic fault diagnosis is critical to en- suring safe and efficient operation. Fault isolation is per- formed by analyzing measured signals...approach in this paper uses a model based on physical equations of the system , and performs fault diagnosis using this model. The proba- bilistic methods...Ying, Kirubarajan, Pattipati, & Patterson-Hine, 2000), in the sense that a proba- bilistic solution is used to perform fault diagnosis in systems with

  13. Isolation of phytosterols and antihyperlipidemic activity of Lagenaria siceraria.

    PubMed

    Kalsait, Ravi P; Khedekar, Pramod B; Saoji, Ashok N; Bhusari, Kishor P

    2011-10-01

    Lagenaria siceraria (Molina) Standl in the Cucurbitaceae family is a large, pubescent, climbing, or trailing herb cultivated throughout India and the tropical regions of the world. Phytochemical investigation of the methanol extract obtained from the fruits of the plant L. siceraria showed a positive Liebermann-Burchard test for sterols. The white sterol crystals or phytosterols from the methanol extract were isolated for the first time and identified as a mixture of four sterols, including fucosterol (1), racemosol (2), stigmasterol (3), and stigmasta-7,22-dien-3β,4β-diol (4). These compounds were identified by spectroscopic evidence including FTIR, (1)H-NMR, MS, and GC. The white sterol crystals, which are the mixture of four sterols, were evaluated for antihyperlipidemic activity in Wistar rats. The blood samples were collected from the retro-orbital plexus and serum was separated and analyzed for lipid profiles. These sterol crystals (30 mg/kg) showed significant reductions in lipid profiles which included cholesterol, triglycerides, LDL and VLDL. In addition, a significant increase in HDL cholesterol observed, which is a good cholesterol that protects hearts from coronary artery diseases. These sterol crystals or phytosterols can be used as an antihyperlipidemic agent to treat the hyperlipidemic.

  14. Active vibration isolation of macro-micro motion stage disturbances using a floating stator platform

    NASA Astrophysics Data System (ADS)

    Zhang, Lufan; Long, Zhili; Cai, Jiandong; Liu, Yang; Fang, Jiwen; Wang, Michael Yu

    2015-10-01

    Macro-micro motion stage is mainly applied in microelectronics manufacturing to realize a high-acceleration, high-speed and nano-positioning motion. The high acceleration and nano-positioning accuracy would be influenced by the vibration of the motion stage. In the paper, a concept of floating stage is introduced in the macro-micro motion for isolating vibration disturbances. The design model of the floating stage is established and its theoretical analyses including natural frequency, transient and frequency response analyses are investigated, in order to demonstrate the feasibility of the floating stator platform as a vibration isolator for the macro-micro motion stage. Moreover, an optimal design of the floating stator is conducted and then verified by experiments. In order to characterize and quantify the performance of isolation obtained from the traditional fixed stator and the floating stator, the acceleration responses at different accelerations, speeds and displacements are measured in x, y and z directions. The theoretical and experimental analyses in time and frequency domains indicate that the floating stator platform is effective to actively isolate the vibration in the macro-micro motion stage. In macro-micro motion stage, high acceleration motion is provided by VCM. Vibration is induced from VCM, that is, VCM is a source system, the vibration response or force is felt by a receiver system. Generally, VCM is fixed on the base, which means that the base is the receiver system which absorbs or transfers the vibration. However, the vibration cannot completely disappear and the base vibration is inevitable. In the paper, a floated stator platform as isolation system is developed to decrease or isolate vibration between VCM and base. The floated stator platform consists of damper, stopper, floated lock, spring, limiter, sub base, etc. Unlike the traditional stator of VCM fixed on the base, the floated stator can be moved on the linear guide under vibration

  15. Nonreciprocity and magnetic-free isolation based on optomechanical interactions

    PubMed Central

    Ruesink, Freek; Miri, Mohammad-Ali; Alù, Andrea; Verhagen, Ewold

    2016-01-01

    Nonreciprocal components, such as isolators and circulators, provide highly desirable functionalities for optical circuitry. This motivates the active investigation of mechanisms that break reciprocity, and pose alternatives to magneto-optic effects in on-chip systems. In this work, we use optomechanical interactions to strongly break reciprocity in a compact system. We derive minimal requirements to create nonreciprocity in a wide class of systems that couple two optical modes to a mechanical mode, highlighting the importance of optically biasing the modes at a controlled phase difference. We realize these principles in a silica microtoroid optomechanical resonator and use quantitative heterodyne spectroscopy to demonstrate up to 10 dB optical isolation at telecom wavelengths. We show that nonreciprocal transmission is preserved for nondegenerate modes, and demonstrate nonreciprocal parametric amplification. These results open a route to exploiting various nonreciprocal effects in optomechanical systems in different electromagnetic and mechanical frequency regimes, including optomechanical metamaterials with topologically non-trivial properties. PMID:27897165

  16. Stable isolated metal atoms as active sites for photocatalytic hydrogen evolution.

    PubMed

    Xing, Jun; Chen, Jian Fu; Li, Yu Hang; Yuan, Wen Tao; Zhou, Ying; Zheng, Li Rong; Wang, Hai Feng; Hu, P; Wang, Yun; Zhao, Hui Jun; Wang, Yong; Yang, Hua Gui

    2014-02-17

    The process of using solar energy to split water to produce hydrogen assisted by an inorganic semiconductor is crucial for solving our energy crisis and environmental problems in the future. However, most semiconductor photocatalysts would not exhibit excellent photocatalytic activity without loading suitable co-catalysts. Generally, the noble metals have been widely applied as co-catalysts, but always agglomerate during the loading process or photocatalytic reaction. Therefore, the utilization efficiency of the noble co-catalysts is still very low on a per metal atom basis if no obvious size effect exists, because heterogeneous catalytic reactions occur on the surface active atoms. Here, for the first time, we have synthesized isolated metal atoms (Pt, Pd, Rh, or Ru) stably by anchoring on TiO2 , a model photocatalystic system, by a facile one-step method. The isolated metal atom based photocatalysts show excellent stability for H2 evolution and can lead to a 6-13-fold increase in photocatalytic activity over the metal clusters loaded on TiO2 by the traditional method. Furthermore, the configurations of isolated atoms as well as the originality of their unusual stability were analyzed by a collaborative work from both experiments and theoretical calculations.

  17. Multi-sensor control for 6-axis active vibration isolation

    NASA Astrophysics Data System (ADS)

    Thayer, Douglas Gary

    The goal of this research is to look at the two different parts of the challenge of active vibration isolation. First is the hardware that will be used to accomplish the task and improve performance. The cubic hexapod, or Stewart platform, has become a popular solution to the problem because of its ability to provide 6-axis vibration isolation with a relatively simple configuration. A number of these hexapods have been constructed at different research facilities around the country to address different missions, each with their own approach. Hood Technology Corporation and the University of Washington took the lessons learned from these designs and developed a new hexapod that addresses the requirements of the Jet Propulsion Laboratory's planned space borne interferometry missions. This system has unique mechanical design details and is built with 4 sensors in each strut. This, along with a real time computer to implement controllers, allows for a great deal of flexibility in controller design and research into sensor selection. Other unique design features include a very soft axial stiffness, a custom designed voice coil actuator with a large displacement capability and elastomeric flexures both for guiding the actuator and providing pivot points on each strut. The second part, and the primary area of this research, is to examine multi-sensor control strategies in an effort to improve the performance of the controllers, their stability and/or how implementable they are. Up to this point, the primary method of control for systems of this type has been classical, designing single-input, single output controller loops to be closed around each strut. But because of the geometry of the hexapod and the different problems that can occur with some sensors, the classical approach is limited in what it can accomplish. This research shows the benefits to be gained by going to a multiple sensor controller and implementing controllers that are designed using a frequency

  18. Skull base osteomyelitis presenting with an isolated hypoglossal nerve palsy

    PubMed Central

    Kasfiki, Eirini Vasileiou; Kelly, Ciaran; Smith, John; Nicolaides, Andreas

    2013-01-01

    This is the first case of skull base osteomyelitis presenting with isolated bilateral hypoglossal nerve palsy reported in the literature. A 75-year-old man presented with tongue paralysis without any other cranial nerve palsy. He was otherwise well apart from recently having a high prostate-specific antigen level recorded. Investigations for malignancy or cerebrovascular insult were negative with the diagnosis of skull base osteomyelitis confirmed using CT. Following treatment with intravenous antibiotics for 6 weeks, symptoms resolved. PMID:23853016

  19. Isolation of glycopeptides with skin test activity from dermatophytes.

    PubMed Central

    Moser, S A; Pollack, J D

    1978-01-01

    By using ethylene glycol extraction of whole submerged cultures followed by Sephadex G-200 and diethylaminoethyl-Sephadex chromatography, we isolated four distinct glycopeptides from Trichophyton mentagrophytes, T. rubrum, and Microsporum canis. Chemical analyses revealed that these glycopeptides contained mostly carbohydrate (42.5 to 81.6%) and protein (4.3 to 11.3%), with lesser amounts of phosphorus (0.4 to 6.0%) and hexosamines (0.3 to 0.6%). Based upon total carbohydrate and monosaccharide content, these dermatophyte glycopeptides could be divided into two chemical groups: glucopeptides (DSI1) and mannopeptides (DSI2, DSII1, and DSII2). The mannopeptides and glucopeptides of each species of dermatophyte were not significantly different chemically from those derived from the other two dermatophyte species studied. Skin testing of DSI1-glycopeptides or DSI2-mannopeptides in immunized guinea pigs indicated that only the DSI2-mannopeptides elicited a delayed hypersensitivity reaction. Skin testing T. mentagrophytes 62-infected guinea pigs with the four purified DS-glycopeptides, as well as earlier fractions from the purification scheme, derived from T. mentagrophytes, T. rubrum, and M. canis, again indicated that only the DSI2-mannopeptides of the two Trichophyton species elicited a delayed hypersensitivity reaction. The number of infections or duration of infection had no effect on the size of the skin test response. DSI2-mannopeptides were non-cross-reactive between genera when tested in Trichophyton-immunized or -infected guinea pigs and Microsporum-immunized guinea pigs. Images PMID:640721

  20. Chitinophaga vermicomposti sp. nov., with antifungal activity, isolated from vermicompost.

    PubMed

    Yasir, Muhammad; Aslam, Zubair; Song, Geun Cheol; Bibi, Fehmida; Jeon, Che Ok; Chung, Young Ryun

    2010-01-01

    A Gram-negative, rod-shaped bacterial strain, YC6729T, was isolated from the vermicompost (VC) collected at Masan, Korea and its taxonomic position was investigated by a polyphasic taxonomic approach. Strain YC6729T grew optimally at 30 degrees C and at pH 6.5-8.5. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain YC6729T belongs to the genus Chitinophaga in the family Chitinophagaceae. Most closely related species are Chitinophaga terra KP01T (96.4 %), Chitinophaga ginsengisegetis Gsoil 040T (96.1 %) and Chitinophaga arvensicola IAM 12650T (96.1 %). Strain YC6729T contained MK-7 as the major menaquinone and homospermidine as the major polyamine. The major fatty acids of strain YC6729T C15:0 iso, C16:1omega5c and C17:0 iso 3-OH. The total DNA G+C content was 48.9 mol%. The phenotypic, chemotaxonomic and phylogenetic data showed that strain YC6729T represents a novel species of the genus Chitinophaga, for which the name Chitinophaga vermicomposti sp. nov. is proposed. The type strain is YC6729T (= KACC 13774T = DSM 22224T).

  1. Double proton transfer in the isolated and DNA-embedded guanine-cytosine base pair

    NASA Astrophysics Data System (ADS)

    Zoete, Vincent; Meuwly, Markus

    2004-09-01

    The energetics and dynamics of double proton transfer (DPT) is investigated theoretically for the Watson-Crick conformation of the guanine-cytosine (GC) base pair. Using semiempirical density functional theory the isolated and DNA-embedded GC pair is considered. Differences in the energetics and dynamics of DPT thus addresses the question of how relevant studies of isolated base pairs are for the understanding of processes occurring in DNA. Two-dimensional potential energy surfaces involving the transferring hydrogen atoms and the proton donors and acceptors are presented for both systems. The DPT reaction is accompanied by a contraction of the distance between the two bases with virtually identical energetic barriers being 18.8 and 18.7 kcal/mol for the isolated and DNA-embedded system, respectively. However, the transition state for DPT in the DNA-embedded GC pair is offset by 0.1 Å to larger N-H separation compared to the isolated GC pair. Using activated ab initio molecular dynamics, DPT is readily observed for the isolated base pair with a minimal amount of 21.4 kcal/mol of initial average kinetic energy along the DPT normal mode vector. On a time scale of ≈100 fs DPT has occurred and the excess energy is redistributed. For the DNA-embedded GC pair considerably more kinetic energy is required (30.0 kcal/mol) for DPT and the process is completed within one hydrogen vibration. The relevance of studies of isolated base pairs and base pair analogs in regard of reactions or properties involving DNA is discussed.

  2. Susceptibility of Escherichia coli isolated from uteri of postpartum dairy cows to antibiotic and environmental bacteriophages. Part I: Isolation and lytic activity estimation of bacteriophages.

    PubMed

    Bicalho, R C; Santos, T M A; Gilbert, R O; Caixeta, L S; Teixeira, L M; Bicalho, M L S; Machado, V S

    2010-01-01

    The objective of this study was to isolate bacteriophages from environmental samples of 2 large commercial dairy farms using Escherichia coli isolated from the uteri of postpartum Holstein dairy cows as hosts. A total of 11 bacteriophage preparations were isolated from manure systems of commercial dairy farms and characterized for in vitro antimicrobial activity. In addition, a total of 57 E. coli uterine isolates from 5 dairy cows were phylogenetically grouped by triplex PCR. Each E. coli bacterial host from the uterus was inoculated with their respective bacteriophage preparation at several different multiplicities of infections (MOI) to determine minimum inhibitory MOI. The effect of a single dose (MOI=10(2)) of bacteriophage on the growth curve of all 57 E. coli isolates was assessed using a microplate technique. Furthermore, genetic diversity within and between the different bacteriophage preparations was assessed by bacteriophage purification followed by DNA extraction, restriction, and agarose gel electrophoresis. Phylogenetic grouping based on triplex PCR showed that all isolates of E. coli belonged to phylogroup B1. Bacterial growth was completely inhibited at considerably low MOI, and the effect of a single dose (MOI=10(2)) of bacteriophage preparations on the growth curve of all 57 E. coli isolates showed that all bacteriophage preparations significantly decreased the growth rate of the isolates. Bacteriophage preparation 1230-10 had the greatest antimicrobial activity and completely inhibited the growth of 71.7% (n=57) of the isolates. The combined action of bacteriophage preparations 1230-10, 6375-10, 2540-4, and 6547-2, each at MOI=10(2), had the broadest spectrum of action and completely inhibited the growth (final optical density at 600 nm isolates and considerably inhibited the growth (final optical density at 600 nm isolates. Restriction profile analysis demonstrated that all 4 phage

  3. Application of a load-bearing passive and active vibration isolation system in hydraulic drives

    NASA Astrophysics Data System (ADS)

    Unruh, Oliver; Haase, Thomas; Pohl, Martin

    2016-09-01

    Hydraulic drives are widely used in many engineering applications due to their high power to weight ratio. The high power output of the hydraulic drives produces high static and dynamic reaction forces and moments which must be carried by the mounts and the surrounding structure. A drawback of hydraulic drives based on rotating pistons consists in multi-tonal disturbances which propagate through the mounts and the load bearing structure and produce structure borne sound at the surrounding structures and cavities. One possible approach to overcome this drawback is to use an optimised mounting, which combines vibration isolation in the main disturbance direction with the capability to carry the reaction forces and moments. This paper presents an experimental study, which addresses the vibration isolation performance of an optimised mounting. A dummy hydraulic drive is attached to a generic surrounding structure with optimised mounting and excited by multiple shakers. In order to improve the performance of the passive vibration isolation system, piezoelectric transducers are applied on the mounting and integrated into a feed-forward control loop. It is shown that the optimised mounting of the hydraulic drive decreases the vibration transmission to the surrounding structure by 8 dB. The presented study also reveals that the use of the active control system leads to a further decrease of vibration transmission of up to 14 dB and also allows an improvement of the vibration isolation in an additional degree of freedom and higher harmonic frequencies.

  4. Spectral characterization and antibacterial activity of an isolated compound from Memecylon edule leaves.

    PubMed

    Srinivasan, R; Natarajan, D; Shivakumar, M S

    2017-03-01

    Memecylon edule Roxb. (Melastamataceae family) is a small evergreen tree reported as having ethnobotanical and pharmacological properties. The present study was aimed to investigate the spectral characterization and antibacterial activity of isolated pure compound (3β-hydroxyurs-12-en-28-oic acid (ursolic acid)) from Memecylon edule leaves by performing bioassay guided isolation method. The structure derivation of isolated compound was done by different spectral studies like UV, FT-IR, LC-MS, CHNS analysis, 1D ((1)H, (13)C and DEPT-135) and 2D-NMR (HSQC and HMBC), respectively. About 99.29% purity of the compound was found in LC analysis. (1)H NMR spectrum results of compound shown 48 protons appear at different shielded region and most of the protons were present in aliphatic region. Whereas, (13)C NMR spectral data resulted seven methyl carbons (CH3), nine methylene carbons (CH2), seven methine carbons (CH) and six non-hydrogenated carbons (C) which are characteristic of pentacyclic triterpene. The isolated pure compound was tested for its antibacterial properties against targeted human pathogens by performing agar well diffusion, MIC and MBC assays and the result exhibits better growth inhibitory effects against S. epidermidis and S. pneumoniae, with the MIC values of 1.56 and 3.15μg/ml. The outcome of this study suggests that the bioactive compound is used for development of plant based drugs in pharmaceutical industry for combating microbial mediated diseases.

  5. Gardnerella vaginalis Subgroups Defined by cpn60 Sequencing and Sialidase Activity in Isolates from Canada, Belgium and Kenya.

    PubMed

    Schellenberg, John J; Paramel Jayaprakash, Teenus; Withana Gamage, Niradha; Patterson, Mo H; Vaneechoutte, Mario; Hill, Janet E

    2016-01-01

    Increased abundance of Gardnerella vaginalis and sialidase activity in vaginal fluid is associated with bacterial vaginosis (BV), a common but poorly understood clinical entity associated with poor reproductive health outcomes. Since most women are colonized with G. vaginalis, its status as a normal member of the vaginal microbiota or pathogen causing BV remains controversial, and numerous classification schemes have been described. Since 2005, sequencing of the chaperonin-60 universal target (cpn60 UT) has distinguished four subgroups in isolate collections, clone libraries and deep sequencing datasets. To clarify potential clinical and diagnostic significance of cpn60 subgroups, we undertook phenotypic and molecular characterization of 112 G. vaginalis isolates from three continents. A total of 36 subgroup A, 33 B, 35 C and 8 D isolates were identified through phylogenetic analysis of cpn60 sequences as corresponding to four "clades" identified in a recently published study, based on sequencing 473 genes across 17 isolates. cpn60 subgroups were compared with other previously described molecular methods for classification of Gardnerella subgroups, including amplified ribosomal DNA restriction analysis (ARDRA) and real-time PCR assays designed to quantify subgroups in vaginal samples. Although two ARDRA patterns were observed in isolates, each was observed in three cpn60 subgroups (A/B/D and B/C/D). Real-time PCR assays corroborated cpn60 subgroups overall, but 13 isolates from subgroups A, B and D were negative in all assays. A putative sialidase gene was detected in all subgroup B, C and D isolates, but only in a single subgroup A isolate. In contrast, sialidase activity was observed in all subgroup B isolates, 3 (9%) subgroup C isolates and no subgroup A or D isolates. These observations suggest distinct roles for G. vaginalis subgroups in BV pathogenesis. We conclude that cpn60 UT sequencing is a robust approach for defining G. vaginalis subgroups within the

  6. Gardnerella vaginalis Subgroups Defined by cpn60 Sequencing and Sialidase Activity in Isolates from Canada, Belgium and Kenya

    PubMed Central

    Schellenberg, John J.; Paramel Jayaprakash, Teenus; Withana Gamage, Niradha; Patterson, Mo H.; Vaneechoutte, Mario; Hill, Janet E.

    2016-01-01

    Increased abundance of Gardnerella vaginalis and sialidase activity in vaginal fluid is associated with bacterial vaginosis (BV), a common but poorly understood clinical entity associated with poor reproductive health outcomes. Since most women are colonized with G. vaginalis, its status as a normal member of the vaginal microbiota or pathogen causing BV remains controversial, and numerous classification schemes have been described. Since 2005, sequencing of the chaperonin-60 universal target (cpn60 UT) has distinguished four subgroups in isolate collections, clone libraries and deep sequencing datasets. To clarify potential clinical and diagnostic significance of cpn60 subgroups, we undertook phenotypic and molecular characterization of 112 G. vaginalis isolates from three continents. A total of 36 subgroup A, 33 B, 35 C and 8 D isolates were identified through phylogenetic analysis of cpn60 sequences as corresponding to four “clades” identified in a recently published study, based on sequencing 473 genes across 17 isolates. cpn60 subgroups were compared with other previously described molecular methods for classification of Gardnerella subgroups, including amplified ribosomal DNA restriction analysis (ARDRA) and real-time PCR assays designed to quantify subgroups in vaginal samples. Although two ARDRA patterns were observed in isolates, each was observed in three cpn60 subgroups (A/B/D and B/C/D). Real-time PCR assays corroborated cpn60 subgroups overall, but 13 isolates from subgroups A, B and D were negative in all assays. A putative sialidase gene was detected in all subgroup B, C and D isolates, but only in a single subgroup A isolate. In contrast, sialidase activity was observed in all subgroup B isolates, 3 (9%) subgroup C isolates and no subgroup A or D isolates. These observations suggest distinct roles for G. vaginalis subgroups in BV pathogenesis. We conclude that cpn60 UT sequencing is a robust approach for defining G. vaginalis subgroups within

  7. Isolation and characterization of broad and ultrapotent human monoclonal antibodies with therapeutic activity against chikungunya virus

    PubMed Central

    Smith, Scott A.; Silva, Laurie A.; Fox, Julie M.; Flyak, Andrew; Kose, Nurgun; Sapparapu, Gopal; Khomadiak, Solomiia; Ashbrook, Alison W.; Kahle, Kristen M.; Fong, Rachel H.; Swayne, Sherri; Doranz, Benjamin J.; McGee, Charles E.; Heise, Mark T.; Pal, Pankaj; Brien, James D.; Austin, S. Kyle; Diamond, Michael S.; Dermody, Terence S.; Crowe, James E.

    2015-01-01

    SUMMARY Chikungunya virus (CHIKV) is a mosquito-transmitted RNA virus that causes acute febrile infection associated with polyarthralgia in humans. Mechanisms of protective immunity against CHIKV are poorly understood, and no effective therapeutics or vaccines are available. We isolated and characterized human monoclonal antibodies (mAbs) that neutralize CHIKV infectivity. Among the 30 mAbs isolated, 13 had broad and ultrapotent neutralizing activity (IC50 < 10 ng/mL), and all of these mapped to domain A of the E2 envelope protein. Potent inhibitory mAbs blocked post-attachment steps required for CHIKV membrane fusion, and several were protective in a lethal challenge model in immunocompromised mice, even when administered at late time points after infection. These highly protective mAbs could be considered for prevention or treatment of CHIKV infection, and their epitope location in domain A of E2 could be targeted for rational structure-based vaccine development. PMID:26159721

  8. Synergistic Effect of Photosynthetic Bacteria and Isolated Bacteria in Their Antifungal Activities against Root Rot Fungi.

    PubMed

    Wei, Hongyi; Okunishi, Suguru; Yoshikawa, Takeshi; Kamei, Yuto; Dawwoda, Mahmoud A O; Santander-DE Leon, Sheila Mae S; Nuñal, Sharon Nonato; Maeda, Hiroto

    2016-01-01

    Antifungal bacteria (AB) in root rot fungus (RRF)-contaminated sweet potato farms were isolated, and seven strains were initially chosen as antagonistic candidates. An antagonistic test by using the mycelial disk placement method revealed that one AB strain by itself could inhibit the RRF growth. This AB strain was identified as Bacillus polyfermenticus based on phylogeny of 16S ribosomal RNA genes. Two AB strains (Bacillus aerophilus) displayed high levels of antifungal activity when paired with photosynthetic bacterial strain A (a purple nonsulfur photosynthetic bacterium Rhodopseudomonas faecalis). The results suggest the possible use of the isolates as agents for the biological control of the RRF infection of agricultural products in fields of cultivation.

  9. Inhibitory activity of Aloe vera gel on some clinically isolated cariogenic and periodontopathic bacteria.

    PubMed

    Fani, Mohammadmehdi; Kohanteb, Jamshid

    2012-03-01

    Aloe vera is a medicinal plant with anti-inflammatory, antimicrobial, antidiabetic and immune-boosting properties. In the present study we investigated the inhibitory activities of Aloe vera gel on some cariogenic (Streptococcus mutans), periodontopathic (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis) and an opportunistic periodontopathogen (Bacteroides fragilis) isolated from patients with dental caries and periodontal diseases. Twenty isolates of each of these bacteria were investigated for their sensitivity to Aloe vera gel using the disk diffusion and microdilution methods. S. mutans was the species most sensitive to Aloe vera gel with a MIC of 12.5 µg/ml, while A. actinomycetemcomitans, P. gingivalis, and B. fragilis were less sensitive, with a MIC of 25-50 µg/ml (P < 0.01). Based on our present findings it is concluded that Aloe vera gel at optimum concentration could be used as an antiseptic for prevention of dental caries and periodontal diseases.

  10. Morphine treatment during juvenile isolation increases social activity and opioid peptides release in the adult rat.

    PubMed

    Van den Berg, C L; Kitchen, I; Gerrits, M A; Spruijt, B M; Van Ree, J M

    1999-05-29

    The consequences of juvenile isolation and morphine treatment on general activity, social activity and endogenous opioid release during a social interaction test were investigated in the adult rat. Rats were either isolated or socially housed during weeks 4 and 5 of age and treated daily during this isolation period subcutaneously with either saline or morphine. Directly after a social interaction test at 10 weeks of age, rats were injected with [3H]-diprenorphine and subsequently prepared for in vivo autoradiography. The autoradiographic technique was used to visualise neuroanatomical changes in opioid receptor occupancy, probably reflecting changes in opioid peptide release, as a result of social activity. Juvenile isolation increased general activity during the social interaction test, an effect which was accompanied by a reduction of opioid receptor occupancy in many brain areas, suggesting an increased opioid peptide release as a consequence of socially-induced general activity. Morphine treatment in isolated rats caused an increase in adult social activity and enhanced opioid peptide release in some cortical regions and the ventral tegmental area as compared to saline treated rats. Both social activity and opioid receptor occupancy were unaffected by morphine treatment in non-isolated rats. The present study underscores the role of opioid systems in adult social behaviors as a consequence of juvenile isolation. The results suggest a relationship between social activity and opioid peptide release during social contact. Increased social activity seems to be accompanied by elevated opioid peptide release in distinct brain areas after morphine treatment during juvenile isolation.

  11. In Vitro Antifungal Activities against Moulds Isolated from Dermatological Specimens

    PubMed Central

    Mohd Nizam, Tzar; Binting, Rabiatul Adawiyah AG.; Mohd Saari, Shafika; Kumar, Thivyananthini Vijaya; Muhammad, Marianayati; Satim, Hartini; Yusoff, Hamidah; Santhanam, Jacinta

    2016-01-01

    Background This study aimed to determine the minimum inhibitory concentrations (MICs) of various antifungal agents against moulds isolated from dermatological specimens. Methods We identified 29 moulds from dermatological specimens between October 2012 and March 2013 by conventional methods. We performed antifungal susceptibility testing on six antifungal agents, amphotericin B, clotrimazole, itraconazole, ketoconazole, miconazole and terbinafine, according to the Clinical and Laboratory Standards Institute guidelines contained in the M38-A2 document. Results Most antifungal agents were active against the dermatophytes, except for terbinafine against Trichophyton rubrum (geometric mean MIC, MICGM 3.17 μg/mL). The dematiaceous moulds were relatively susceptible to amphotericin B and azoles (MICGM 0.17–0.34 μg/mL), but not to terbinafine (MICGM 3.62 μg/mL). Septate hyaline moulds showed variable results between the relatively more susceptible Aspergillus spp. (MICGM 0.25–4 μg/mL) and the more resistant Fusarium spp. (MICGM 5.66–32 μg/mL). The zygomycetes were susceptible to amphotericin B (MICGM 0.5 μg/mL) and clotrimazole (MICGM 0.08 μg/mL), but not to other azoles (MICGM 2.52–4 μg/mL). Conclusion Amphotericin B and clotrimazole were the most effective antifungal agents against all moulds excepting Fusarium spp., while terbinafine was useful against dermatophytes (except T. rubrum) and Aspergillus spp. However, a larger study is required to draw more solid conclusions. PMID:27418867

  12. Antimicrobial activity of bacterial isolates from different floral sources of honey.

    PubMed

    Lee, Hyungjae; Churey, John J; Worobo, Randy W

    2008-08-15

    More than two thousand bacterial strains isolated from six US domestic honeys and two manuka honeys from New Zealand were screened for production of antimicrobial compounds. A high incidence of antimicrobial inhibition determined by deferred inhibition assays was observed with the bacterial isolates from all eight honey samples. In total, 2217 isolates out of 2398 strains (92.5% of total isolates) exhibited antimicrobial activity against at least one of the tested microorganisms. Antifungal activity by bacterial isolates originating from the eight honeys ranged from 44.4% to 98.0%. Bacterial isolates from manuka honey (MH1) exhibited antimicrobial activity against Bacillus subtilis ATCC 6633 and Bacillus cereus F4552, at 51.5% and 53.3% of the isolates, respectively. However, less than 30% of the bacterial isolates from the other manuka honey (MH2) and six domestic honey sources exhibited anti-Bacillus activity. Listeria monocytogenes F2-586 1053 showed higher overall rates of sensitivity to between 11 and 66% of the bacterial isolates. The high rate of antimicrobial activity exhibited by the bacterial strains isolated from different honey sources could provide potential sources of novel antimicrobial compounds.

  13. ADVANCED SEISMIC BASE ISOLATION METHODS FOR MODULAR REACTORS

    SciTech Connect

    E. Blanford; E. Keldrauk; M. Laufer; M. Mieler; J. Wei; B. Stojadinovic; P.F. Peterson

    2010-09-20

    Advanced technologies for structural design and construction have the potential for major impact not only on nuclear power plant construction time and cost, but also on the design process and on the safety, security and reliability of next generation of nuclear power plants. In future Generation IV (Gen IV) reactors, structural and seismic design should be much more closely integrated with the design of nuclear and industrial safety systems, physical security systems, and international safeguards systems. Overall reliability will be increased, through the use of replaceable and modular equipment, and through design to facilitate on-line monitoring, in-service inspection, maintenance, replacement, and decommissioning. Economics will also receive high design priority, through integrated engineering efforts to optimize building arrangements to minimize building heights and footprints. Finally, the licensing approach will be transformed by becoming increasingly performance based and technology neutral, using best-estimate simulation methods with uncertainty and margin quantification. In this context, two structural engineering technologies, seismic base isolation and modular steel-plate/concrete composite structural walls, are investigated. These technologies have major potential to (1) enable standardized reactor designs to be deployed across a wider range of sites, (2) reduce the impact of uncertainties related to site-specific seismic conditions, and (3) alleviate reactor equipment qualification requirements. For Gen IV reactors the potential for deliberate crashes of large aircraft must also be considered in design. This report concludes that base-isolated structures should be decoupled from the reactor external event exclusion system. As an example, a scoping analysis is performed for a rectangular, decoupled external event shell designed as a grillage. This report also reviews modular construction technology, particularly steel-plate/concrete construction using

  14. Rhizobium borbori sp. nov., aniline-degrading bacteria isolated from activated sludge.

    PubMed

    Zhang, Guo Xia; Ren, Sui Zhou; Xu, Mei Ying; Zeng, Guo Qu; Luo, Hui Dong; Chen, Jin Lin; Tan, Zhi Yuan; Sun, Guo Ping

    2011-04-01

    Three aniline-degrading bacteria, strains DN316(T), DN316-1 and DN365, were isolated from activated sludge. According to 16S rRNA gene sequence-based phylogenetic analysis, the isolates belonged to the genus Rhizobium, with Rhizobium ( = Agrobacterium) radiobacter LMG 140(T) as the closest relative, with 96.5 % sequence similarity. Phylogenetic analysis of the representative strain DN316(T) using sequences of the glnA, thrC and recA genes and the 16S-23S intergenic spacer region confirmed the phylogenetic arrangement obtained from analysis of the 16S rRNA gene. DNA-DNA relatedness between DN316(T) and R. radiobacter LMG 140(T) was 43.7 %, clearly indicating that the representative strain DN316(T) represents a novel species. Phenotypic and biochemical characterization of the isolates and insertion sequence-PCR fingerprinting patterns showed several distinctive features that differentiated them from closely related species. The major components of the cellular fatty acids were C(18 : 1)ω7c (57.10 %), C(16 : 0) (11.31 %) and C(19 : 0) cyclo ω8c (10.13 %). Based on our taxonomic analysis, the three isolates from activated sludge represent a novel species of the genus Rhizobium, for which the name Rhizobium borbori sp. nov. is proposed. The type strain is DN316(T) ( = CICC 10378(T)  = LMG 23925(T)).

  15. A "Kane's Dynamics" Model for the Active Rack Isolation System Part Two: Nonlinear Model Development, Verification, and Simplification

    NASA Technical Reports Server (NTRS)

    Beech, G. S.; Hampton, R. D.; Rupert, J. K.

    2004-01-01

    Many microgravity space-science experiments require vibratory acceleration levels that are unachievable without active isolation. The Boeing Corporation's active rack isolation system (ARIS) employs a novel combination of magnetic actuation and mechanical linkages to address these isolation requirements on the International Space Station. Effective model-based vibration isolation requires: (1) An isolation device, (2) an adequate dynamic; i.e., mathematical, model of that isolator, and (3) a suitable, corresponding controller. This Technical Memorandum documents the validation of that high-fidelity dynamic model of ARIS. The verification of this dynamics model was achieved by utilizing two commercial off-the-shelf (COTS) software tools: Deneb's ENVISION(registered trademark), and Online Dynamics Autolev(trademark). ENVISION is a robotics software package developed for the automotive industry that employs three-dimensional computer-aided design models to facilitate both forward and inverse kinematics analyses. Autolev is a DOS-based interpreter designed, in general, to solve vector-based mathematical problems and specifically to solve dynamics problems using Kane's method. The simplification of this model was achieved using the small-angle theorem for the joint angle of the ARIS actuators. This simplification has a profound effect on the overall complexity of the closed-form solution while yielding a closed-form solution easily employed using COTS control hardware.

  16. Possible correlation between levansucrase production and probiotic activity of Bacillus sp. isolated from honey and honey bee.

    PubMed

    Hamdy, Abdelhamid A; Elattal, Nouran A; Amin, Magdy A; Ali, Amal E; Mansour, Nahla M; Awad, Ghada E A; Awad, Hassan M; Esawy, Mona A

    2017-04-01

    Five bacterial isolates from honey and bee gut were selected based on their high levansucrase activity and levan yield which were strongly positively correlated. All isolates showed good tolerance to temperature up to 70 °C, to NaCl up to 3 M and to 0.1% H2O2. They maintained over 59 and 64% survival at pH 9.0 and 2.0 respectively, but showed varying tolerance to 0.1% bile salts and pancreatic enzymes. Most isolates were susceptible to widely used antibiotics, but demonstrated diverse antimicrobial activity. Non hemolytic isolates were identified on the basis of 16S rRNA sequencing as Bacillus subtilis HMNig-2 and B. subtilis MENO2 with 97% homology. They exhibited promising probiotic characteristics and achieved highest levansucrase activity of 94.1 and 81.5 U/mL respectively. Both exhibited highest biofilm formation ability in static microtiter plate assay. Also, they achieved 34 and 26% adhesion respectively to Caco-2cells and had highest free radical scavenging activity of 30.8 and 26.2% respectively. The levans of the two isolates showed good antimicrobial activity against some pathogens and exhibited positive prebiotic effect (prebiotic index >1) with Lactobacillus casei and Lactobacillus reuteri. Results suggest a correlation between levansucrase production, levan yield and pre-probiotic activities of the studied strains.

  17. The Development of an Intelligent Hybrid Active-passive Vibration Isolator

    NASA Astrophysics Data System (ADS)

    Shuai, Changgeng; Ma, Jianguo; Rustighi, Emiliano

    2016-09-01

    A hybrid active-passive vibration isolator made up of electromagnetic actuator and air spring in parallel can be used to effectively isolate the broadband and line spectrum vibration of mechanical equipment simultaneously. However, due to its reliability and safety problems caused by the impact, its application in ships is limited. In this paper, an impact- resistant structure and an air gap self-sensing method of the passive-active hybrid vibration isolator are proposed and developed on the base of modelling, simulation and analysis. A thin magnetic rubber is filled into the air gap of electromagnetic actuator, which can avoid rigid collision between the armature and the permanent magnet under the action of impact. A suspension armature structure including pre-compression spring is suggested, which can automatically compensate the deformation caused by impact and protect the coil and permanent magnet from impact damage. An air gap self-sensing method is developed through detecting the voltage between the input and output terminals of actuator, which is verified by experiments.

  18. A MEMBRANE FILTER PROCEDURE FOR ASSAYING CYTOTOXIC ACTIVITY IN HETEROTROPHIC BACTERIA ISOLATED FROM DRINKING WATER

    EPA Science Inventory

    Cytotoxic activity assays of Gram-negative, heterotrophic bacteria are often laborious and time consuming. The objective of this study was to develop in situ procedures for testing potential cytotoxic activities of heterotrophic bacteria isolated from drinking water systems. Wate...

  19. [Fungal activity of various alkaloids isolated from Catharanthus roseus G. Don].

    PubMed

    Rojas Hernández, N M; Díaz Pérez, C

    1977-01-01

    Evaluation is made of the fungal activity of ajmalicine, aparacine, catarantine, reserpine, tetrahydroalstonine, vincubine, vindoline and vindolinina--alkaloids isolated from C. roseus growing in Cuba--on new fungi strains and yeasts which include some of human clinical interest. The method employed was the diffusion in an agar mean with sections or cylinders containing solutions of the alkaloids at 2% and 3% concentrations. The best results are obtained with an aparicine base, while tetrahydroalstonine, vincubine and vindolinine solutions did not inhibit the growth in any of the germs tested.

  20. Enhancement of antibiotic activity by efflux inhibitors against multidrug resistant Mycobacterium tuberculosis clinical isolates from Brazil.

    PubMed

    Coelho, Tatiane; Machado, Diana; Couto, Isabel; Maschmann, Raquel; Ramos, Daniela; von Groll, Andrea; Rossetti, Maria L; Silva, Pedro A; Viveiros, Miguel

    2015-01-01

    Drug resistant tuberculosis continues to increase and new approaches for its treatment are necessary. The identification of M. tuberculosis clinical isolates presenting efflux as part of their resistant phenotype has a major impact in tuberculosis treatment. In this work, we used a checkerboard procedure combined with the tetrazolium microplate-based assay (TEMA) to study single combinations between antituberculosis drugs and efflux inhibitors (EIs) against multidrug resistant M. tuberculosis clinical isolates using the fully susceptible strain H37Rv as reference. Efflux activity was studied on a real-time basis by a fluorometric method that uses ethidium bromide as efflux substrate. Quantification of efflux pump genes mRNA transcriptional levels were performed by RT-qPCR. The fractional inhibitory concentrations (FIC) indicated synergistic activity for the interactions between isoniazid, rifampicin, amikacin, ofloxacin, and ethidium bromide plus the EIs verapamil, thioridazine and chlorpromazine. The FICs ranged from 0.25, indicating a four-fold reduction on the MICs, to 0.015, 64-fold reduction. The detection of active efflux by real-time fluorometry showed that all strains presented intrinsic efflux activity that contributes to the overall resistance which can be inhibited in the presence of the EIs. The quantification of the mRNA levels of the most important efflux pump genes on these strains shows that they are intrinsically predisposed to expel toxic compounds as the exposure to subinhibitory concentrations of antibiotics were not necessary to increase the pump mRNA levels when compared with the non-exposed counterpart. The results obtained in this study confirm that the intrinsic efflux activity contributes to the overall resistance in multidrug resistant clinical isolates of M. tuberculosis and that the inhibition of efflux pumps by the EIs can enhance the clinical effect of antibiotics that are their substrates.

  1. Endophytic fungus strain 28 isolated from Houttuynia cordata possesses wide-spectrum antifungal activity.

    PubMed

    Pan, Feng; Liu, Zheng-Qiong; Chen, Que; Xu, Ying-Wen; Hou, Kai; Wu, Wei

    2016-01-01

    The aim of this paper is to identify and investigate an endophytic fungus (strain 28) that was isolated from Houttuynia cordata Thunb, a famous and widely-used Traditional Chinese Medicine. Based on morphological methods and a phylogenetic analysis of ITS sequences, this strain was identified as Chaetomium globosum. An antifungal activity bioassay demonstrated that the crude ethyl acetate (EtOAc) extracts of strain 28 had a wide antifungal spectrum and strong antimicrobial activity, particularly against Exserohilum turcicum (Pass.) Leonard et Suggs, Botrytis cinerea persoon and Botrytis cinerea Pers. ex Fr. Furthermore, the fermentation conditions, extraction method and the heat stability of antifungal substances from strain 28 were also studied. The results showed that optimal antifungal activity can be obtained with the following parameters: using potato dextrose broth (PDB) as the base culture medium, fermentation for 4-8d (initial pH: 7.5), followed by extraction with EtOAc. The extract was stable at temperatures up to 80°C. This is the first report on the isolation of endophytic C. globosum from H. cordata to identify potential alternative biocontrol agents that could provide new opportunities for practical applications involving H. cordata.

  2. Capacitor-based isolation amplifiers for harsh radiation environments

    NASA Astrophysics Data System (ADS)

    Franco, Francisco J.; Zong, Yi; de Agapito, Juan A.

    2010-01-01

    Commercial-off-the-shelf (COTS) capacitor-based isolation amplifiers were irradiated at the Portuguese Research Reactor (PRR) in order to determine its tolerance to the displacement damage and total ionising dose (TID). The set of experimental data shows that some of these devices are suitable for zones inside future nuclear facilities where the expected total radiation damage would be below 2.2×1013 1-MeV neutron/cm2 and 230 Gy (Si). However, some drawbacks must be taken into account by the electronic designers such as the increase of the output offset voltage and the slight modification of the transmission gain.

  3. Technology transfer package on seismic base isolation - Volume III

    SciTech Connect

    1995-02-14

    This Technology Transfer Package provides some detailed information for the U.S. Department of Energy (DOE) and its contractors about seismic base isolation. Intended users of this three-volume package are DOE Design and Safety Engineers as well as DOE Facility Managers who are responsible for reducing the effects of natural phenomena hazards (NPH), specifically earthquakes, on their facilities. The package was developed as part of DOE's efforts to study and implement techniques for protecting lives and property from the effects of natural phenomena and to support the International Decade for Natural Disaster Reduction. Volume III contains supporting materials not included in Volumes I and II.

  4. Seismic Response Analysis and Design of Structure with Base Isolation

    SciTech Connect

    Rosko, Peter

    2010-05-21

    The paper reports the study on seismic response and energy distribution of a multi-story civil structure. The nonlinear analysis used the 2003 Bam earthquake acceleration record as the excitation input to the structural model. The displacement response was analyzed in time domain and in frequency domain. The displacement and its derivatives result energy components. The energy distribution in each story provides useful information for the structural upgrade with help of added devices. The objective is the structural displacement response minimization. The application of the structural seismic response research is presented in base-isolation example.

  5. In Vitro Activity of ASP2397 against Aspergillus Isolates with or without Acquired Azole Resistance Mechanisms

    PubMed Central

    Jensen, Rasmus Hare; Cuenca-Estrella, Manuel

    2015-01-01

    ASP2397 is a new compound with a novel and as-yet-unknown target different from that of licensed antifungal agents. It has activity against Aspergillus and Candida glabrata. We compared its in vitro activity against wild-type and azole-resistant A. fumigatus and A. terreus isolates with that of amphotericin B, itraconazole, posaconazole, and voriconazole. Thirty-four isolates, including 4 wild-type A. fumigatus isolates, 24 A. fumigatus isolates with alterations in CYP51A TR/L98H (5 isolates), M220 (9 isolates), G54 (9 isolates), and HapE (1 isolate), and A. terreus isolates (2 wild-type isolates and 1 isolate with an M217I CYP51A alteration), were analyzed. EUCAST E.Def 9.2 and CLSI M38-A2 MIC susceptibility testing was performed. ASP2397 MIC50 values (in milligrams per liter, with MIC ranges in parentheses) determined by EUCAST and CLSI were 0.5 (0.25 to 1) and 0.25 (0.06 to 0.25) against A. fumigatus CYP51A wild-type isolates and were similarly 0.5 (0.125 to >4) and 0.125 (0.06 to >4) against azole-resistant A. fumigatus isolates, respectively. These values were comparable to those for amphotericin B, which were 0.25 (0.125 to 0.5) and 0.25 (0.125 to 0.25) against wild-type isolates and 0.25 (0.125 to 1) and 0.25 (0.125 to 1) against isolates with azole resistance mechanisms, respectively. In contrast, MICs for the azole compounds were elevated and highest for itraconazole: >4 (1 to >4) and 4 (0.5 to >4) against isolates with azole resistance mechanisms compared to 0.125 (0.125 to 0.25) and 0.125 (0.06 to 0.25) against wild-type isolates, respectively. ASP2397 was active against A. terreus CYP51A wild-type isolates (MIC 0.5 to 1), whereas MICs of both azole and ASP2397 were elevated for the mutant isolate. ASP2397 displayed in vitro activity against A. fumigatus and A. terreus isolates which was independent of the presence or absence of azole target gene resistance mutations in A. fumigatus. The findings are promising at a time when azole-resistant A. fumigatus

  6. Isolation, transformation, anticancer, and apoptosis activity of lupeyl acetate from Artocarpus integra

    NASA Astrophysics Data System (ADS)

    Suwito, Hery; Heffen, Wan Lelly; Cahyana, Herry; Suwarso, Wahyudi Priyono

    2016-03-01

    Lupeyl acetate -a major constituent of the bark of Artocarpus integra- was isolated and then transformed chemically into lupeol and lupenone by hydrolysis and oxidation reaction respectively. The molecular structures of the prepared compounds were determined based on FTIR, MS and NMR spectrum evidences. Their anticancer activities were determined against breast cancer cells MCF-7 using neutral red assay, while their apoptotic activity were confirmed by flowcytometric analysis using Annexin V-FTIC assay and DNA fragmentation. The IC50 of Lupeyl acetate, lupeol, and lupenone were 48.79; 43.09; and 8.07 µg/mL respectively. The results of flowcytometric analysis and DNA fragmentation showed that anticancer activity of the prepared compounds following apoptosis mechanism.

  7. Active Narrow-Band Vibration Isolation of Large Engineering Structures

    NASA Technical Reports Server (NTRS)

    Rahman, Zahidul; Spanos, John

    1994-01-01

    We present a narrow-band tracking control method using a variant of the Least Mean Squares (LMS) algorithm to isolate slowly changing periodic disturbances from engineering structures. The advantage of the algorithm is that it has a simple architecture and is relatively easy to implement while it can isolate disturbances on the order of 40-50 dB over decades of frequency band. We also present the results of an experiment conducted on a flexible truss structure. The average disturbance rejection achieved is over 40 dB over the frequency band of 5 Hz to 50 Hz.

  8. Smooth muscle relaxing activity of gentiopicroside isolated from Gentiana spathacea.

    PubMed

    Rojas, A; Bah, M; Rojas, J I; Gutiérrez, D M

    2000-12-01

    Bioassay directed fractionation of the (1:1) chloroform-methanol extract of Gentiana spathacea H.B.K (Gentianaceae) led to the isolation of gentiopicroside (gentiopricrin) (1), the major spasmolytic component of the plant. Gentiopicroside inhibited, in a concentration-dependent manner, the spontaneous contractions of isolated guinea pig ileum. Contractions induced by histamine, acetylcholine, BaCl2 and KCl on the ileum were also significantly blocked by this monoterpene glucoside, which suggests that this compound might be interfering with calcium influx into the smooth muscle cells.

  9. Characterization of Bacillus thuringiensis soil isolates from Cuba, with insecticidal activity against mosquitoes.

    PubMed

    González, Aileen; Díaz, Raúl; Díaz, Manuel; Borrero, Yainais; Bruzón, Rosa Y; Carreras, Bertha; Gato, René

    2011-09-01

    Chemical insecticides may be toxic and cause environmental degradation. Consequently, biological control for insects represents an alternative with low ecological impact. In this work, three soil isolates (A21, A51 and C17) from different regions of the Cuban archipelago were identified, characterized and evaluated against Aedes aegypti and Culex quinquefasciatus. The new isolates were compared with reference IPS82 strain and two strains isolated from biolarvicides Bactivec and Bactoculicida, respectively. The differentiation was done by morphological, biochemical, bioassays activity and molecular methods (SDS-PAGE, plasmid profile and random amplified polymorphic analysis). All isolates were identified as Bacillus thuringiensis. The A21, A51 and C17 isolates showed higher larvicide activity than Bactivec's isolated reference strain, against both A. aegypti and C. quinquefasciatus. A21 isolate had a protein profile similar to IPS82 and Bactivec strain. A51 and C17 isolates produced a characteristic proteins pattern. A21 and A51 isolates had plasmid patterns similar to IPS82 standard strain, while C17 isolate had different both plasmid profile and protein bands. All the studied isolates showed a diverse RAPD patterns and were different from the strains previously used in biological control in Cuba.

  10. Antischistosomal Activity of Two Active Constituents Isolated from the Leaves of Egyptian Medicinal Plants

    PubMed Central

    Ali, Sanaa A; El-Regal, Nagy S; Saeed, Samar M

    2015-01-01

    In this paper, we investigate the role of two active constituents isolated from the leaves of Egyptian medicinal plants. D-mannitol a naturally occurring sugar isolated from the leaves Ixora undulata Roxb., and the pectin a linear chain homogalacturonan (HG) polysaccharide isolated from the leaves of Linum grandiflorum Desf. (scarlet flax). Both are evaluated for their therapeutic effect against schistosomiasis with biochemical and histochemical evaluations and compared with praziquantel, a reference drug. Biochemical studies of hepatic glucose, the glycogen content, and total serum protein were carried out, and histochemical evaluations through serum protein fractions separated by polyacrylamide gel electrophoresis with different molecular weights (260–10 kDa) were made in all groups, in addition to liver and body weight. D-mannitol and pectin show a remarkable effect in enhancing liver and kidney functions through enhancing most protein fractions in the serum of mice infected with Schistosoma mansoni. Also, the glucose and glycogen content in injured liver tissues improved, in addition liver and body weight in the infected groups. Thus they may be of therapeutic potential in the treatment hepatoxicity and nephrotoxicity. PMID:26124666

  11. Antimicrobial Activities of Some Actinomycetes Isolated from Different Rhizospheric Soils in Tunisia.

    PubMed

    Trabelsi, Ines; Oves, Daniel; Manteca, Angel; Genilloud, Olga; Altalhi, Abdullah; Nour, Mohamed

    2016-08-01

    Fifty four isolates of actinomycetes were collected from four different rhizospheric soils: 18 strains from palm tree bark and soil, 12 strains from an olive field soil, 9 strains from a coastal forest, and 15 strains from an agriculture soil situated in the Algerian-Tunisian border (Oum Tboul). Based on morphological and cultural characters, the isolates were classified as Streptomyces (42 strains), Micromonospora (4 strains), Pseudonocardia (1 strain), Actinomadura (1 strain), Nocardia (1 strain), and non-Streptomyces (5 strains). More than half of the isolates inhibited at least one tested pathogenic microorganisms in liquid culture. In addition, antimicrobial activities of some strains were tested on solid culture. Several bioactive compounds were identified by liquid chromatography joined with low-resolution mass spectroscopy (LC/MS) and analysed by MEDINA's database and by the dictionary of natural products Chapman & Hall. An interesting chlorinated compound with the molecular formula C20H37ClN2O4, produced by three different strains (SF1, SF2, and SF5), was subject of an attempted purification. However, it was demonstrated using confocal microscopy and LC/MS high resolution that this compound is produced only on solid culture. These three potential antimicrobial isolates showed high similarity with Streptomyces thinghirensis and Streptomyces lienomycini, in terms of morphological characteristics and 16S rRNA gene sequences (bootstrap 97 %). All these findings prove the high antimicrobial diversity of the studied soils. The potential of the selected and other relatively unexplored extreme environments constitute a source of interesting actinomycete strains producing several biologically active secondary metabolites.

  12. FACS-based isolation, propagation and characterization of mouse embryonic cardiomyocytes based on VCAM-1 surface marker expression.

    PubMed

    Pontén, Annica; Walsh, Stuart; Malan, Daniela; Xian, Xiaojie; Schéele, Susanne; Tarnawski, Laura; Fleischmann, Bernd K; Jovinge, Stefan

    2013-01-01

    Purification of cardiomyocytes from the embryonic mouse heart, embryonic stem (ES) or induced pluripotent stem cells (iPS) is a challenging task and will require specific isolation procedures. Lately the significance of surface markers for the isolation of cardiac cell populations with fluorescence activated cell sorting (FACS) has been acknowledged, and the hunt for cardiac specific markers has intensified. As cardiomyocytes have traditionally been characterized by their expression of specific transcription factors and structural proteins, and not by specific surface markers, this constitutes a significant bottleneck. Lately, Flk-1, c-kit and the cellular prion protein have been reported to specify cardiac progenitors, however, no surface markers have so far been reported to specify a committed cardiomyocyte. Herein show for the first time, that embryonic cardiomyocytes can be isolated with 98% purity, based on their expression of vascular cell adhesion molecule-1 (VCAM-1). The FACS-isolated cells express phenotypic markers for embryonic committed cardiomyocytes but not cardiac progenitors. An important aspect of FACS is to provide viable cells with retention of functionality. We show that VCAM-1 positive cardiomyocytes can be isolated with 95% viability suitable for in vitro culture, functional assays or expression analysis. In patch-clamp experiments we provide evidence of functionally intact cardiomyocytes of both atrial and ventricular subtypes. This work establishes that cardiomyocytes can be isolated with a high degree of purity and viability through FACS, based on specific surface marker expression as has been done in the hematopoietic field for decades. Our FACS protocol represents a significant advance in which purified populations of cardiomyocytes may be isolated and utilized for downstream applications, such as purification of ES-cell derived cardiomyocytes.

  13. a Hybrid-Type Active Vibration Isolation System Using Neural Networks

    NASA Astrophysics Data System (ADS)

    Ahn, K. G.; Pahk, H. J.; Jung, M. Y.; Cho, D. W.

    1996-05-01

    Vibration isolation of mechanical systems is achieved through either passive or active vibration control systems. Although a passive vibration isolation system offers simple and reliable means to protect mechanical systems from a vibration environment, it has inherent performance limitations, that is, its controllable frequency range is limited and the shape of its transmissibility does not change. Recently, in some applications, such as active suspensions or precise vibration systems, active vibration isolation systems have been employed to overcome the limitations of the passive systems. In this paper, a hybrid-type active vibration isolation system that uses electromagnetic and pneumatic force is developed, and a new control algorithm adopting neural networks is proposed. The characteristics of the hybrid system proposed in the paper were investigated via computer simulation and experiments. It was shown that the transmissibility of the vibration isolation system could be kept below 0.63 over the entire frequency range, including the resonance frequency.

  14. The occurrence of killer activity in yeasts isolated from natural habitats.

    PubMed

    Wójcik, Monika; Kordowska-Wiater, Monika

    2015-01-01

    Yeast's ability to restrict the growth and kill other yeasts, fungi and bacteria has been known for over 50 years. Killer activity was detected in yeasts deposited in the world collections or isolated from natural habitats. In this study, isolates from the forest environment, leaves of fruit trees, flower petals, cereals and frozen fruit have been screened in terms of their killer activities. Killer activity was tested on strains belonging to six yeast species: Candida, Rhodotorula, Pichia, Pachysolen, Yarrowia, Trichosporon. The reference strains were Kluyveromyces lactis Y-6682 and Kluyveromyces marxinanus Y-8281, well-known to be sensitive to yeast killer toxins. Among one hundred and two tested strains, 24 (23.5% of isolates) showed positive killer action, and 10 (9.8% of the isolates) a weak killer action against at least one sensitive reference strain. The highest killer activity was observed among isolates from forest soil and flowers.

  15. Arousal and hallucinatory activity under two isolation conditions

    NASA Technical Reports Server (NTRS)

    Levin, J.

    1974-01-01

    Experimental exploration of the hypothesis that soundproof-room and water-immersion isolation environments differ with respect to the variety of physiological responses and reported hallucinations they elicit. The results obtained support the hypothesis in regard to physiological responses only.

  16. Design and optimization of voice coil actuator for six degree of freedom active vibration isolation system using Halbach magnet array.

    PubMed

    Kim, MyeongHyeon; Kim, Hyunchang; Gweon, Dae-Gab

    2012-10-01

    This paper describes the design, modeling, optimization, and validation of an active vibration isolation system using a voice coil motor. The active vibration isolating method was constructed with a passive isolator and an active isolator. A spring was used for passive isolating; an actuator was used for active isolating. The proposed active vibration isolation system (AVIS) can isolate disturbances for many kinds of instruments. Until now, developed AVIS were able to isolate a six degree-of-freedom disturbance effectively. This paper proposes the realization of such a six degree-of-freedom active vibration isolation system that can work as a bench top device for precision measuring machines such as atomic force microscope, scanning probe microscope, etc.

  17. Investigation on active vibration isolation of a Stewart platform with piezoelectric actuators

    NASA Astrophysics Data System (ADS)

    Wang, Chaoxin; Xie, Xiling; Chen, Yanhao; Zhang, Zhiyi

    2016-11-01

    A Stewart platform with piezoelectric actuators is presented for micro-vibration isolation. The Jacobi matrix of the Stewart platform, which reveals the relationship between the position/pointing of the payload and the extensions of the six struts, is derived by kinematic analysis. The dynamic model of the Stewart platform is established by the FRF (frequency response function) synthesis method. In the active control loop, the direct feedback of integrated forces is combined with the FxLMS based adaptive feedback to dampen vibration of inherent modes and suppress transmission of periodic vibrations. Numerical simulations were conducted to prove vibration isolation performance of the Stewart platform under random and periodical disturbances, respectively. In the experiment, the output consistencies of the six piezoelectric actuators were measured at first and the theoretical Jacobi matrix as well as the feedback gain of each piezoelectric actuator was subsequently modified according to the measured consistencies. The direct feedback loop was adjusted to achieve sufficient active damping and the FxLMS based adaptive feedback control was adopted to suppress vibration transmission in the six struts. Experimental results have demonstrated that the Stewart platform can achieve 30 dB attenuation of periodical disturbances and 10-20 dB attenuation of random disturbances in the frequency range of 5-200 Hz.

  18. Semi-active magnetorheological seat suspensions for enhanced crashworthiness and vibration isolation of rotorcraft seats

    NASA Astrophysics Data System (ADS)

    Hiemenz, Gregory J.

    current state-of-the-art rotorcraft seat suspensions which can provide no better than 20% risk of occupant injury. Finally, an MR-based seat suspension designed solely for the purposes of vibration isolation was designed, analyzed, and experimentally demonstrated. MR dampers were integrated into the current crashworthy SH-60 crew seat with minimal weight impact such that the original crashworthy capabilities were maintained. Then, utilizing semi-active control, experimental vibration testing demonstrated that the system reduced vertical cockpit vibrations transmitted to the occupant by 76%. This is a significant advance over current state-of-the-art rotorcraft seats which provide no attenuation of cockpit vibrations.

  19. Isolation and biological activities of phenanthroindolizidine and septicine alkaloids from the Formosan Tylophora ovata.

    PubMed

    Lee, Yue-Zhi; Huang, Chun-Wei; Yang, Cheng-Wei; Hsu, Hsing-Yu; Kang, Iou-Jiun; Chao, Yu-Sheng; Chen, Ih-Sheng; Chang, Hwan-You; Lee, Shiow-Ju

    2011-11-01

    An investigation of alkaloids present in the leaves and stems of Tylophora ovata led to the isolation of two new septicine alkaloids and one new phenanthroindolizidine alkaloid, tylophovatines A, B, C (1, 2, and 5), respectively, together with two known septicine and six known phenanthroindolizidine alkaloids. The structures of the new alkaloids 1, 2, and 5 were established by means of spectroscopic analyses. These eleven alkaloids show in vitro anti-inflammatory activities with IC₅₀ values ranging from 84 nM to 20.6 μM through their suppression of nitric oxide production in RAW264.7 cells stimulated by lipopolysaccharide and interferon-γ. Moreover, these substances display growth inhibition in HONE-1, NUGC-3, HepG2, SF-268, MCF-7, and NCI-H460 cancer cell lines, with GI₅₀ values ranging from 4 nM to 24.2 μM. In addition, tylophovatine C (5) and 13a(S)-(+)-tylophorine (7) were found to exhibit potent in vivo anti-inflammation activities in a rat paw edema model. Finally, structure–activity relationships were probed by using the isolated phenanthroindolizidines and septicines. Phenanthroindolizidines are suggested to be divided into cytotoxic agents (e.g., 10 and 11) and anti-inflammation based anticancer agents (e.g., 5–9).

  20. Rapid isolation of a facultative anaerobic electrochemically active bacterium capable of oxidizing acetate for electrogenesis and azo dyes reduction.

    PubMed

    Shen, Nan; Yuan, Shi-Jie; Wu, Chao; Cheng, Yuan-Yuan; Song, Xiang-Ning; Li, Wen-Wei; Tong, Zhong-Hua; Yu, Han-Qing

    2014-05-01

    In this study, 27 strains of electrochemically active bacteria (EAB) were rapidly isolated and their capabilities of extracellular electron transfer were identified using a photometric method based on WO3 nanoclusters. These strains caused color change of WO3 from white to blue in a 24-well agar plate within 40 h. Most of the isolated EAB strains belonged to the genera of Aeromonas and Shewanella. One isolate, Pantoea agglomerans S5-44, was identified as an EAB that can utilize acetate as the carbon source to produce electricity and reduce azo dyes under anaerobic conditions. The results confirmed the capability of P. agglomerans S5-44 for extracellular electron transfer. The isolation of this acetate-utilizing, facultative EBA reveals the metabolic diversity of environmental bacteria. Such strains have great potential for environmental applications, especially at interfaces of aerobic and anaerobic environments, where acetate is the main available carbon source.

  1. Isolation and Analysis of Novel Electrochemically Active Bacteria for Enhanced Power Generation in Microbial Fuel Cells

    DTIC Science & Technology

    2009-03-07

    ISOLATION AND ANALYSIS OF NOVEL ELECTROCHEMICALLY ACTIVE BACTERIA FOR ENHANCED POWER GENERATION IN MICROBIAL FUEL CELLS B.E. Logan, J.M. Regan...new exoelectrogenic bacteria during this project. We isolated Rhodopseudomonas palustris DX-1, and demonstrated for the first time that a pure culture... isolated Ochrobactrum anthropi YZ-1, which had the remarkable characteristic that it was unable to respire using hydrous Fe(lll) oxide but produced

  2. Antimicrobial activities of novel cultivable bacteria isolated from marine sponge Tedania anhelans

    NASA Astrophysics Data System (ADS)

    Zeng, Zhen; Zhao, Jing; Ke, Caihuan; Wang, Dexiang

    2013-05-01

    Marine sponge Tedania anhelans distributes throughout the intertidal zone of Fujian, southeastern China, and is a potential source of natural bioactive products. The sponge harbors a large number of bacterial groups that have been identified using various techniques, including fluorescent in situ hybridization (FISH). Fractionation of dissociated sponge allowed isolation of 25 bacterial species. Based on 16S rRNA gene sequencing, phylogenetic analysis attributed most of these eubacteria to α- Proteobacteria, γ- Proteobacteria, Cytophaga / Flavobacterium / Bacteroidetes (CFB group), and the family Bacillaceae of Gram-positive bacteria. In sequence similarity, five putatively novel species were identified with less than 98% similarity to other strains in the NCBI database. Tests for antimicrobial activities were performed against Gram-positive bacteria, Gram-negative bacteria, fungi, antitumor indicators Escherichia coli 343/591 (with DNA repair deficiency), regular E. coli 343/636 (with different DNA repair capacity), and 10 bacterial isolates exhibited inhibitory bioactivities. Among these strains, three isolates were detected involving function gene NRPS-A domains, which were most closely related to the amino acid sequences of linear gramicidin synthetase and pyoverdine synthetase. These results contribute to our knowledge of the microbes associated with marine sponges and further reveal novel bacterial resources for the screening of bioactive marine natural products.

  3. Antimicrobial Activity of Monoramnholipids Produced by Bacterial Strains Isolated from the Ross Sea (Antarctica) †

    PubMed Central

    Tedesco, Pietro; Maida, Isabel; Palma Esposito, Fortunato; Tortorella, Emiliana; Subko, Karolina; Ezeofor, Chidinma Christiana; Zhang, Ying; Tabudravu, Jioji; Jaspars, Marcel; Fani, Renato; de Pascale, Donatella

    2016-01-01

    Microorganisms living in extreme environments represent a huge reservoir of novel antimicrobial compounds and possibly of novel chemical families. Antarctica is one of the most extraordinary places on Earth and exhibits many distinctive features. Antarctic microorganisms are well known producers of valuable secondary metabolites. Specifically, several Antarctic strains have been reported to inhibit opportunistic human pathogens strains belonging to Burkholderia cepacia complex (Bcc). Herein, we applied a biodiscovery pipeline for the identification of anti-Bcc compounds. Antarctic sub-sea sediments were collected from the Ross Sea, and used to isolate 25 microorganisms, which were phylogenetically affiliated to three bacterial genera (Psychrobacter, Arthrobacter, and Pseudomonas) via sequencing and analysis of 16S rRNA genes. They were then subjected to a primary cell-based screening to determine their bioactivity against Bcc strains. Positive isolates were used to produce crude extracts from microbial spent culture media, to perform the secondary screening. Strain Pseudomonas BNT1 was then selected for bioassay-guided purification employing SPE and HPLC. Finally, LC-MS and NMR structurally resolved the purified bioactive compounds. With this strategy, we achieved the isolation of three rhamnolipids, two of which were new, endowed with high (MIC < 1 μg/mL) and unreported antimicrobial activity against Bcc strains. PMID:27128927

  4. In vitro activity of tigecycline and comparators against gram-negative bacteria isolated from a tertiary hospital in Alexandria, Egypt.

    PubMed

    Mohamed, Nelly M; Youssef, Alaa A F

    2011-12-01

    The emergence of infections caused by multidrug-resistant Gram-negative bacteria, in particular Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae, has necessitated the search for alternative therapy by either introducing new agents or renewing interest in old agents. This study compares the in vitro activity of tigecycline (TIG), recently introduced to Egyptian market, to other potentially active antimicrobials as Colistin (COL), imipenem (IPM), levofloxacin (LEV), and piperacillin/tazobactam (PIP/TAZ) against 67 Gram-negative clinical isolates obtained from El- Meery Hospital in Alexandria, Egypt. El-Meery Hospital is a 1,500-bed tertiary teaching hospital where TIG has not been previously used. Based on MIC(90)s, TIG was found to be a comparator to IPM and COL (MIC(90)= 8 μg/ml). LEV and PIP/TAZ were less active than TIG exhibiting high MIC(90)s. TIG inhibited 100% of Escherichia coli and K. pneumoniae and 60% of Ps. aeruginosa and A. baumannii isolates. In time-kill studies against IPM-resistant isolates, TIG showed bactericidal activity after 6 hours of contact against the Enterobacteriaceae isolates and after 3 hours for the tested Ps. aeruginosa isolates at 4× and 8× MIC. Against A. baumannii, TIG exerted a bacteriostatic effect. TIG demonstrated variable ability to suppress biofilm formation affecting mainly E. coli and A. baumannii isolates. These results point TIG to be a promising agent in treatment of infections caused by strains for which adequate therapy has been limited. As far as we know, this is the first report evaluating the in vitro activity of TIG against Egyptian clinical isolates.

  5. Disturbance detection and isolation in the activated sludge process.

    PubMed

    Yoo, C K; Choi, S W; Lee, I

    2002-01-01

    This paper proposes a new fault detection and isolation (FDI) method. This method monitors the distribution of process data and detects changes in this distribution, which reflect changes in the corresponding operating condition. A modified dissimilarity index and a FDI technique are defined to quantitatively evaluate the difference between data sets. This technique considers the importance of each transformed variable in the multivariate system. The FDI technique is applied to a benchmark simulation and to data from a real wastewater treatment plant. Simulation results show that it immediately detects disturbances and automatically distinguishes between serious and minor anomalies for various types of fault. The method not only detects the disturbances, but also isolates the scale of the disturbance, facilitating the interpretation of the disturbance source. The proposed monitoring technique is found to be appropriate for analyzing the biological wastewater treatment process, which is characterized by a variety of fault and disturbance sources and non-stationary characteristics.

  6. Development and characterization of a magnetorheological elastomer based adaptive seismic isolator

    NASA Astrophysics Data System (ADS)

    Li, Yancheng; Li, Jianchun; Li, Weihua; Samali, Bijan

    2013-03-01

    One of the main shortcomings in current base isolation design/practice is lack of adaptability. As a result, a base isolation system that is effective for one type earthquake may become ineffective or may have adverse effect for other earthquakes. The vulnerability of traditional base isolation systems can be exaggerated by two types of earthquakes, i.e. near-field earthquakes and far-field earthquakes. This paper addresses the challenge facing current base isolation design/practice by proposing a new type of seismic isolator for the base isolation system, namely an adaptive seismic isolator. The novel adaptive seismic isolator utilizes magnetorheological elastomer (MRE) for its field-sensitive material property. Traditional seismic isolator design with a unique laminated structure of steel and MRE layers has been adopted in the novel MRE seismic isolator. To evaluate and characterize the behavior of the MRE seismic isolator, experimental testing was conducted on a shake table facility under harmonic cycling loading. Experimental results show that the proposed adaptive seismic isolator can successfully alter the lateral stiffness and damping force in real time up to 37% and 45% respectively. Based on the successful development of the novel adaptive seismic isolator, a discussion is also extended to the impact and potential applications of such a device in structural control applications in civil engineering.

  7. Identification and Antimicrobial Activity Detection of Lactic Acid Bacteria Isolated from Corn Stover Silage

    PubMed Central

    Li, Dongxia; Ni, Kuikui; Pang, Huili; Wang, Yanping; Cai, Yimin; Jin, Qingsheng

    2015-01-01

    A total of 59 lactic acid bacteria (LAB) strains were isolated from corn stover silage. According to phenotypic and chemotaxonomic characteristics, 16S ribosomal DNA (rDNA) sequences and recA gene polymerase chain reaction amplification, these LAB isolates were identified as five species: Lactobacillus (L.) plantarum subsp. plantarum, Pediococcus pentosaceus, Enterococcus mundtii, Weissella cibaria and Leuconostoc pseudomesenteroides, respectively. Those strains were also screened for antimicrobial activity using a dual-culture agar plate assay. Based on excluding the effects of organic acids and hydrogen peroxide, two L. plantarum subsp. plantarum strains ZZU 203 and 204, which strongly inhibited Salmonella enterica ATCC 43971T, Micrococcus luteus ATCC 4698T and Escherichia coli ATCC 11775T were selected for further research on sensitivity of the antimicrobial substance to heat, pH and protease. Cell-free culture supernatants of the two strains exhibited strong heat stability (60 min at 100°C), but the antimicrobial activity was eliminated after treatment at 121°C for 15 min. The antimicrobial substance remained active under acidic condition (pH 2.0 to 6.0), but became inactive under neutral and alkaline condition (pH 7.0 to 9.0). In addition, the antimicrobial activities of these two strains decreased remarkably after digestion by protease K. These results preliminarily suggest that the desirable antimicrobial activity of strains ZZU 203 and 204 is the result of the production of a bacteriocin-like substance, and these two strains with antimicrobial activity could be used as silage additives to inhibit proliferation of unwanted microorganism during ensiling and preserve nutrients of silage. The nature of the antimicrobial substances is being investigated in our laboratory. PMID:25924957

  8. Cyclic modulation of semi-active controllable dampers for tonal vibration isolation

    NASA Astrophysics Data System (ADS)

    Anusonti-Inthra, P.; Gandhi, F.

    2004-08-01

    The present study examines the potential of using a semi-active controllable damper, whose damping coefficient can be modulated in real time, for tonal vibration isolation applications. A frequency-domain control algorithm is developed for determining the damping coefficient variation (at twice the disturbance frequency) that minimizes the force transmitted to the support at the disturbance frequency. The effectiveness of open-loop, closed-loop, and adaptive controllers in rejecting the transmitted disturbances are evaluated. The results of the study indicate that when limits in damping coefficient variation are considered, the support force could be reduced by about an additional 30%, beyond the levels due to the passive isolation characteristics (no cyclic damping modulation). When the disturbance phase changes during operation, the effectiveness of the open-loop controller is rapidly degraded. While the closed-loop controller (with inputs based on current levels of force transmitted to the support) performed better, there was still some degradation in performance, and transmitted support forces were not reduced to levels prior to the change in disturbance phase. The results show that for the semi-active system to retain its effectiveness in rejecting disturbances, a closed-loop, adaptive controller (with on-line system identification) is required; even when there is only a change in disturbance, and no change in basic system properties. An explanation for this phenomenon, related to the bi-linear nature of the semi-active system, is provided. Cyclic modulations in the damping coefficient were more effective in reducing the transmitted forces at the disturbance frequency than simply reducing the baseline damping coefficient (to improve the passive isolation characteristics).

  9. Quantification, antioxidant and antimicrobial activity of phenolics isolated from different extracts of Capsicum frutescens (Pimenta Malagueta).

    PubMed

    Nascimento, Patrícia L A; Nascimento, Talita C E S; Ramos, Natália S M; Silva, Girliane R; Gomes, José Erick Galindo; Falcão, Rosângela E A; Moreira, Keila A; Porto, Ana L F; Silva, Tania M S

    2014-04-24

    This paper presents the quantification, antioxidant and antimicrobial activity of capsaicin, dihydrocapsaicin and the flavonoid chrysoeriol isolated from different extracts (hexane and acetonitrile extracts from whole fruit, peel and seed) of Capsicum frutescens (pimenta malagueta). The acetonitrile extract of the seeds, peel and whole fruits contained capsaicin as a major component, followed in abundance by dihydrocapsaicin and chrysoeriol. The antimicrobial activity of the isolated compounds against seven microorganisms showed chrysoeriol was the most active compound. In the antioxidant test, the acetonitrile extract from the whole fruit showed the highest activity. The antioxidant activity of pimenta malagueta may be correlated with its phenolic content, principally with the most active compound, capsaicin.

  10. Antipoliovirus Activity of the Organic Extract of Eupatorium buniifolium: Isolation of Euparin as an Active Compound

    PubMed Central

    Visintini Jaime, María Florencia; Campos, Rodolfo H.; Martino, Virginia S.; Cavallaro, Lucía V.; Muschietti, Liliana V.

    2013-01-01

    The antiviral activity of the organic extract (OE) of Eupatorium buniifolium against poliovirus type 1 was determined by in vitro assays with an effective concentration 50 (EC50) of 23.3 ± 3.3 µg/mL. Bioassay-guided fractionation of the OE allowed the isolation of an active principle that was identified by spectroscopic methods (1H- and 13C-NMR, EI-MS, UV, and IR spectroscopy) as the benzofuran euparin. The plaque reduction assay in Vero cells was used to assess the antiviral activity of euparin against poliovirus types 1, 2, and 3 with EC50 values of 0.47, 0.12, and 0.15 µg/mL, respectively. Moreover, this compound showed high selectivity indexes of 284.9, 1068, and 854.7, respectively. In order to identify the mechanism by which euparin exerts its antiviral activity, the virucidal effect, the pretreatment of Vero cells, and the time of action on one viral replication cycle were evaluated. Results obtained demonstrated that euparin exerts its effect during the early events of the replication cycle, from the virus adsorption to cells up to the first twenty minutes after infection. This is the first report on the presence of euparin in E. buniifolium and its antiviral activity. PMID:23956770

  11. Using FAIRE (Formaldehyde-Assisted Isolation of Regulatory Elements) to isolate active regulatory DNA

    PubMed Central

    Simon, Jeremy M.; Giresi, Paul G.; Davis, Ian J.; Lieb, Jason D.

    2013-01-01

    Eviction or destabilization of nucleosomes from chromatin is a hallmark of functional regulatory elements of the eukaryotic genome. Historically identified by nuclease hypersensitivity, these regulatory elements are typically bound by transcription factors or other regulatory proteins. FAIRE (Formaldehyde-Assisted Isolation of Regulatory Elements) is an alternative approach to identify these genomic regions and has proven successful in a multitude of eukaryotic cell and tissue types. Cells or dissociated tissues are crosslinked briefly with formaldehyde, lysed, and sonicated. Sheared chromatin is subjected to phenol-chloroform extraction and the isolated DNA, typically encompassing 1–3% of the human genome, is purified. We provide guidelines for quantitative analysis by PCR, microarrays, or next-generation sequencing. Regulatory elements enriched by FAIRE display high concordance with those identified by nuclease hypersensitivity or ChIP, and the entire procedure can be completed in three days. FAIRE exhibits low technical variability, which allows its use in large-scale studies of chromatin from normal or diseased tissues. PMID:22262007

  12. Decarboxylation activity of enterococci isolated from rabbit meat and staphylococci isolated from trout intestines.

    PubMed

    Pleva, Pavel; Buňková, Leona; Lauková, Andrea; Lorencová, Eva; Kubáň, Vlastimil; Buňka, František

    2012-10-12

    The aim of the study was to explore production of seven biogenic amines (phenylethylamine, histamine, cadaverine, tyramine, putrescine, spermine and/or spermidine) by selected staphylococci and enterococci. Thirty three enterococcal strains isolated from rabbit meat (Oryctolagus cuniculus f. domesticus) and 21 staphylococcal strains isolated from intestinal content of trout (Salmo trutta morpha fario) were tested. Production of biogenic amines was evaluated after cultivation of the tested microorganisms in the de Man, Rogosa and Sharpe Broth (enterococci) or in the Brain Heart Infusion Broth (staphylococci). Both the above cultivation media were enriched with selected amino acids (histidine, tyrosine, arginine, ornithine and lysine; 2g/L each) serving as precursors of biogenic amines. After cultivation, levels of the monitored biogenic amines in broths were analysed by a high performance liquid chromatography equipped with a UV/VIS DAD detector. Among 21 staphylococci, 18 strains produced tyramine or cadaverine, 13 strains formed putrescine or phenylethylamine and only one strain generated histamine. Two staphylococcal strains produced cadaverine levels above 1000 mg/L. Among 33 enterococcal strains, 27 formed cadaverine, 18 strains produced tyramine, 10 strains generated phenylethylamine, and 2 strains gave putrescine. Most of the tyramine producing enterococci generated more than 1000 mg/L of this biogenic amine. Production of spermine or spermidine by the studied strains was not proved.

  13. Activity of telavancin and comparator antimicrobial agents tested against Staphylococcus spp. isolated from hospitalised patients in Europe (2007-2008).

    PubMed

    Mendes, Rodrigo E; Sader, Helio S; Jones, Ronald N

    2010-10-01

    The activity of telavancin was evaluated against Staphylococcus spp. collected from European hospitals as part of an international surveillance study (2007-2008). A total of 7534 staphylococcal clinical isolates [5726 Staphylococcus aureus and 1808 coagulase-negative staphylococci (CoNS)] were included. Isolates were tested for susceptibility according to reference methods and minimum inhibitory concentration (MIC) values were interpreted based on Clinical and Laboratory Standards Institute (CLSI) 2010 and European Committee on Antimicrobial Susceptibility Testing (EUCAST) 2009 criteria. Telavancin breakpoints approved by the US Food and Drug Administration (FDA) were applied. Telavancin activity was evaluated against meticillin-resistant S. aureus (MRSA) displaying several antibiogram resistance patterns, including multidrug-resistant isolates. Telavancin was active against S. aureus [MIC(50/90) values (MICs for 50% and 90% of the isolates, respectively)=0.12/0.25mg/L; 100.0% susceptible] and CoNS (MIC(50/90)=0.12/0.25mg/L), inhibiting all isolates at < or =0.5mg/L. Similar results were observed when S. aureus were stratified by year or country of origin (MIC(50/90)=0.12/0.25mg/L). When MRSA isolates were clustered according to 48 different resistance patterns, telavancin showed consistent MIC(90) values (0.25mg/L) regardless of multidrug resistance. Amongst CoNS, telavancin was slightly more active against Staphylococcus capitis, Staphylococcus epidermidis, Staphylococcus hominis, Staphylococcus lugdunensis and Staphylococcus xylosus (MIC(50)=0.12 mg/L) compared with Staphylococcus haemolyticus, Staphylococcus saprophyticus and Staphylococcus warneri (MIC(50)=0.25mg/L). Overall, telavancin exhibited MIC(90) results two- to eight-fold lower than comparators (daptomycin, quinupristin/dalfopristin, vancomycin and linezolid). Based upon MIC(90) values, telavancin demonstrated potent in vitro activity against a contemporary (2007-2008) collection of Staphylococcus spp

  14. Mass Measurements of Isolated Objects from Space-based Microlensing

    NASA Astrophysics Data System (ADS)

    Zhu, Wei; Calchi Novati, S.; Gould, A.; Udalski, A.; Han, C.; Shvartzvald, Y.; Ranc, C.; Jørgensen, U. G.; Poleski, R.; Bozza, V.; Beichman, C.; Bryden, G.; Carey, S.; Gaudi, B. S.; Henderson, C. B.; Pogge, R. W.; Porritt, I.; Wibking, B.; Yee, J. C.; SPITZER Team; Pawlak, M.; Szymański, M. K.; Skowron, J.; Mróz, P.; Kozłowski, S.; Wyrzykowski, Ł.; Pietrukowicz, P.; Pietrzyński, G.; Soszyński, I.; Ulaczyk, K.; OGLE Group; Choi, J.-Y.; Park, H.; Jung, Y. K.; Shin, I.-G.; Albrow, M. D.; Park, B.-G.; Kim, S.-L.; Lee, C.-U.; Cha, S.-M.; Kim, D.-J.; Lee, Y.; KMTNET Group; Friedmann, M.; Kaspi, S.; Maoz, D.; WISE Group; Hundertmark, M.; Street, R. A.; Tsapras, Y.; Bramich, D. M.; Cassan, A.; Dominik, M.; Bachelet, E.; Dong, Subo; Figuera Jaimes, R.; Horne, K.; Mao, S.; Menzies, J.; Schmidt, R.; Snodgrass, C.; Steele, I. A.; Wambsganss, J.; RoboNeT Team; Skottfelt, J.; Andersen, M. I.; Burgdorf, M. J.; Ciceri, S.; D'Ago, G.; Evans, D. F.; Gu, S.-H.; Hinse, T. C.; Kerins, E.; Korhonen, H.; Kuffmeier, M.; Mancini, L.; Peixinho, N.; Popovas, A.; Rabus, M.; Rahvar, S.; Tronsgaard, R.; Scarpetta, G.; Southworth, J.; Surdej, J.; von Essen, C.; Wang, Y.-B.; Wertz, O.; MiNDSTEP Group

    2016-07-01

    We report on the mass and distance measurements of two single-lens events from the 2015 Spitzer microlensing campaign. With both finite-source effect and microlens parallax measurements, we find that the lens of OGLE-2015-BLG-1268 is very likely a brown dwarf (BD). Assuming that the source star lies behind the same amount of dust as the Bulge red clump, we find the lens is a 45 ± 7 {M}{{J}} BD at 5.9 ± 1.0 kpc. The lens of of the second event, OGLE-2015-BLG-0763, is a 0.50 ± 0.04 {M}⊙ star at 6.9 ± 1.0 kpc. We show that the probability to definitively measure the mass of isolated microlenses is dramatically increased once simultaneous ground- and space-based observations are conducted.

  15. Energy and Transmissibility in Nonlinear Viscous Base Isolators

    NASA Astrophysics Data System (ADS)

    Markou, Athanasios A.; Manolis, George D.

    2016-09-01

    High damping rubber bearings (HDRB) are the most commonly used base isolators in buildings and are often combined with other systems, such as sliding bearings. Their mechanical behaviour is highly nonlinear and dependent on a number of factors. At first, a physical process is suggested here to explain the empirical formula introduced by J.M. Kelly in 1991, where the dissipated energy of a HDRB under cyclic testing, at constant frequency, is proportional to the amplitude of the shear strain, raised to a power of approximately 1.50. This physical process is best described by non-Newtonian fluid behaviour, originally developed by F.H. Norton in 1929 to describe creep in steel at high-temperatures. The constitutive model used includes a viscous term, that depends on the absolute value of the velocity, raised to a non-integer power. The identification of a three parameter Kelvin model, the simplest possible system with nonlinear viscosity, is also suggested here. Furthermore, a more advanced model with variable damping coefficient is implemented to better model in this complex mechanical process. Next, the assumption of strain-rate dependence in their rubber layers under cyclic loading is examined in order to best interpret experimental results on the transmission of motion between the upper and lower surfaces of HDRB. More specifically, the stress-relaxation phenomenon observed with time in HRDB can be reproduced numerically, only if the constitutive model includes a viscous term, that depends on the absolute value of the velocity raised to a non-integer power, i. e., the Norton fluid previously mentioned. Thus, it becomes possible to compute the displacement transmissibility function between the top and bottom surfaces of HDRB base isolator systems and to draw engineering-type conclusions, relevant to their design under time-harmonic loads.

  16. Impact on growth and aflatoxin B1 accumulation by Kluyveromyces isolates at different water activity conditions.

    PubMed

    Penna, Mariángeles La; Etcheverry, Miriam

    2006-11-01

    This study showed the impact on germination, mycelial growth and aflatoxin B(1) accumulation when interacting Aspergillus aflatoxigenic strains with Kluyveromyces isolates and the effect of water activity on this relationship. Isolates Y(14) and Y(16) reduced the percentage of germination of all Aspergillus strains and decrease germ tube elongation rate at majority of water activity assayed. Similarly they produced an increase of germination lag phase and lag phase of growth beside decreased growth rate of all Aspergillus strains. At water activities 0.994, 0.982, 0.955 and 0.937, no aflatoxins were produced in paired cultures with isolates Y(25,) Y(22), Y(16), and Y(14), and Kluyveromyces isolates Y(14) and Y(16) impact both growth and aflatoxin accumulation at wide range of water activity.

  17. Isolation, biological activity, synthesis, and medicinal chemistry of the pederin/mycalamide family of natural products.

    PubMed

    Mosey, R Adam; Floreancig, Paul E

    2012-09-01

    This review highlights the broad range of science that has arisen from the isolation of pederin, the mycalamides, theopederins, and onnamides, and psymberin. Specific topics include structure determination, biological activity, synthesis, and analog preparation and analysis.

  18. Static calibration of the RSRA active-isolator rotor balance system

    NASA Technical Reports Server (NTRS)

    Acree, C. W., Jr.

    1987-01-01

    The Rotor Systems Research Aircraft (RSRA) active-isolator system is designed to reduce rotor vibrations transmitted to the airframe and to simultaneously measure all six forces and moments generated by the rotor. These loads are measured by using a combination of load cells, strain gages, and hydropneumatic active isolators with built-in pressure gages. The first static calibration of the complete active-isolator rotor balance system was performed in l983 to verify its load-measurement capabilities. Analysis of the data included the use of multiple linear regressions to determine calibration matrices for different data sets and a hysteresis-removal algorithm to estimate in-flight measurement errors. Results showed that the active-isolator system can fulfill most performance predictions. The results also suggested several possible improvements to the system.

  19. Isolation and anticancer, anthelminthic, and antiviral (HIV) activity of acylphloroglucinols, and regioselective synthesis of empetrifranzinans from Hypericum roeperianum.

    PubMed

    Fobofou, Serge Alain Tanemossu; Franke, Katrin; Sanna, Giuseppina; Porzel, Andrea; Bullita, Enrica; La Colla, Paolo; Wessjohann, Ludger A

    2015-10-01

    From the ethno-medicinally used leaves of Hypericum roeperianum we isolated a new tricyclic acylphloroglucinol (1), a new tetracyclic acylphloroglucinol (2), and a new prenylated bicyclic acylphloroglucinol (3) together with four known prenylated (4-7) and three known tetracyclic acylphloroglucinol derivatives (8-10). Structure elucidation was based on UV, IR, [α]D(25), 1D- and 2D-NMR experiments. Furthermore, empetrifranzinans A (8) and C (9) were synthesized regioselectively in only two steps. The isolated compounds were evaluated for their cytotoxicity against PC-3 and HT-29 cancer cell lines as well as antibacterial and anthelmintic activities. They were also tested in cell-based assays for cytotoxicity against MT-4 cells and for anti-HIV activity in infected MT-4 cells. Significant anthelmintic activity against Caenorhabditis elegans was exhibited by compound 7 (3-geranyl-1-(2'-methylbutanoyl)-phloroglucinol), which might provide a new lead.

  20. Antibacterial activity of isolated phenolic compounds from cranberry (Vaccinium macrocarpon) against Escherichia coli.

    PubMed

    Rodríguez-Pérez, Celia; Quirantes-Piné, Rosa; Uberos, José; Jiménez-Sánchez, Cecilia; Peña, Alejandro; Segura-Carretero, Antonio

    2016-03-01

    Phenolic compounds from a cranberry extract were isolated in order to assess their contribution to the antibacterial activity against uropathogenic strains of Escherichia coli (UPEC). With this purpose, a total of 25 fractions from a cranberry extract were isolated using semipreparative high performance liquid chromatography (HPLC) and characterized based on the results obtained by reversed-phase HPLC coupled to mass spectrometry detection. Then, the effects on UPEC surface hydrophobicity and biofilm formation of the cranberry extract as well as the purest fractions (a total of 13) were tested. As expected, the whole extract presented a powerful antibacterial activity against UPEC while the selected fractions presented a different behavior. Myricetin and quercitrin significantly decreased (p < 0.05) E. coli biofilm formation compared with the control, while dihydroferulic acid glucuronide, procyanidin A dimer, quercetin glucoside, myricetin and prodelphinidin B led to a significant decrease of the surface hydrophobicity compared with the control. The results suggest that apart from proanthocyanidins, other compounds, mainly flavonoids, can act against E. coli biofilm formation and also modify UPEC surface hydrophobicity in vitro, one of the first steps of adhesion.

  1. High Milk-Clotting Activity Expressed by the Newly Isolated Paenibacillus spp. Strain BD3526.

    PubMed

    Hang, Feng; Liu, Peiyi; Wang, Qinbo; Han, Jin; Wu, Zhengjun; Gao, Caixia; Liu, Zhenmin; Zhang, Hao; Chen, Wei

    2016-01-12

    Paenibacillus spp. BD3526, a bacterium exhibiting a protein hydrolysis circle surrounded with an obvious precipitation zone on skim milk agar, was isolated from raw yak (Bos grunniens) milk collected in Tibet, China. Phylogenetic analysis based on 16S rRNA and whole genome sequence comparison indicated the isolate belong to the genus Paenibacillus. The strain BD3526 demonstrated strong ability to produce protease with milk clotting activity (MCA) in wheat bran broth. The protease with MCA was predominantly accumulated during the late-exponential phase of growth. The proteolytic activity (PA) of the BD3526 protease was 1.33-fold higher than that of the commercial R. miehei coagulant. A maximum MCA (6470 ± 281 SU mL(-1)) of the strain BD3526 was reached under optimal cultivation conditions. The protease with MCA was precipitated from the cultivated supernatant of wheat bran broth with ammonium sulfate and purified by anion-exchange chromatography. The molecular weight of the protease with MCA was determined as 35 kDa by sodium dodecyl sulfate-polyacrylamide gels electrophoresis (SDS-PAGE) and gelatin zymography. The cleavage site of the BD3526 protease with MCA in κ-casein was located at the Met106-Ala107 bond, as determined by mass spectrometry analysis.

  2. Antitussive activity of polysaccharides isolated from the Malian medicinal plants.

    PubMed

    Sutovská, M; Franová, S; Priseznaková, L; Nosálová, G; Togola, A; Diallo, D; Paulsen, B S; Capek, P

    2009-04-01

    From the leaves of popular Malian medicinal plants Trichilia emetica (TE) and Opilia celtidifolia (OC), and fruits of Crossopteryx febrifuga (CF) water and water-ethanol soluble polysaccharide materials were isolated. The results of chemical analysis of the crude polysaccharides showed the dominance of the arabinogalactan ( approximately 54%) and the rhamnogalacturonan ( approximately 30%) in T. emetica leaves, the arabinogalactan ( approximately 60%), the rhamnogalacturonan ( approximately 14%) and the glucuronoxylan ( approximately 14%) in O. celtidifolia leaves, and pectic type of polysaccharides ( approximately 75%) with a lower content of the arabinogalactan ( approximately 17%) in C. febrifuga fruits. The plant polysaccharides showed various biological effects on the citric acid-induced cough reflex and reactivity of airways smooth muscle in vivo conditions. T. emetica and O. celtidifolia polysaccharides possessed significant cough-suppressive effect on chemically induced cough. Furthermore, values of specific airways resistance pointed on bronchodilatory property of polysaccharides isolated from O. celtidifolia. However, the crude extract from C. febrifuga in the same dose as T. emetica and O. celtidifolia did not influence the experimentally induced cough as well as reactivity of airways smooth muscle despite of the fact that the water-ethanol extract is recommended for cough therapy in Mali in the form of syrup.

  3. Genetic diversity and antimicrobial activity of endophytic Myrothecium spp. isolated from Calophyllum apetalum and Garcinia morella.

    PubMed

    Ruma, Karmakar; Sunil, Kumar; Kini, Kukkundoor R; Prakash, Harischandra Sripathy

    2015-11-01

    Calophyllum apetalum and Garcinia morella, medicinal plants are endemic to Western Ghats, Karnataka, India. Sixteen Myrothecium isolates were obtained from the tissues of bark and twigs of these plants. The purpose of this study was to explore the antimicrobial activity and genetic variability of the endophytic Myrothecium isolates. The antimicrobial activity as well as the genetic diversity of endophytic Myrothecium species was investigated through RAPD, ISSR and ITS sequence analysis. Myrothecium isolates were genotypically compared by RAPD and ISSR techniques, 510 and 189 reproducible polymorphic bands were obtained using 20 RAPD and ten ISSR primers respectively. The isolates grouped into four main clades and subgroups using unweighted pair group method with arithmetic mean cluster analysis. rDNA ITS sequence analysis presented better resolution for characterising the isolates of Myrothecium spp. The clustering patterns of the isolates were almost similar when compared with RAPD and ISSR dendograms. The results signify that RAPD, ISSR and ITS analysis can be employed to distinguish the genetic diversity of the Myrothecium species. The endophytic and pathogenic strains were compared by maximum parsimony, maximum likelihood and neighbour joining methods. One isolate (JX862206) amongst the 16 Myrothecium isolates exhibited potent antibacterial and as well as anti-Candida activity.

  4. Phylogenetic diversity and biological activity of actinobacteria isolated from the Chukchi Shelf marine sediments in the Arctic Ocean.

    PubMed

    Yuan, Meng; Yu, Yong; Li, Hui-Rong; Dong, Ning; Zhang, Xiao-Hua

    2014-03-06

    Marine environments are a rich source of Actinobacteria and have the potential to produce a wide variety of biologically active secondary metabolites. In this study, we used four selective isolation media to culture Actinobacteria from the sediments collected from the Chukchi Shelf in the Arctic Ocean. A total of 73 actinobacterial strains were isolated. Based on repetitive DNA fingerprinting analysis, we selected 30 representatives for partial characterization according to their phylogenetic diversity, antimicrobial activities and secondary-metabolite biosynthesis genes. Results from the 16S rRNA gene sequence analysis indicated that the 30 strains could be sorted into 18 phylotypes belonging to 14 different genera: Agrococcus, Arsenicicoccus, Arthrobacter, Brevibacterium, Citricoccus, Janibacter, Kocuria, Microbacterium, Microlunatus, Nocardioides, Nocardiopsis, Saccharopolyspora, Salinibacterium and Streptomyces. To our knowledge, this paper is the first report on the isolation of Microlunatus genus members from marine habitats. Of the 30 isolates, 11 strains exhibited antibacterial and/or antifungal activity, seven of which have activities against Bacillus subtilis and Candida albicans. All 30 strains have at least two biosynthetic genes, one-third of which possess more than four biosynthetic genes. This study demonstrates the significant diversity of Actinobacteria in the Chukchi Shelf sediment and their potential for producing biologically active compounds and novel material for genetic manipulation or combinatorial biosynthesis.

  5. Phylogenetic Diversity and Biological Activity of Actinobacteria Isolated from the Chukchi Shelf Marine Sediments in the Arctic Ocean

    PubMed Central

    Yuan, Meng; Yu, Yong; Li, Hui-Rong; Dong, Ning; Zhang, Xiao-Hua

    2014-01-01

    Marine environments are a rich source of Actinobacteria and have the potential to produce a wide variety of biologically active secondary metabolites. In this study, we used four selective isolation media to culture Actinobacteria from the sediments collected from the Chukchi Shelf in the Arctic Ocean. A total of 73 actinobacterial strains were isolated. Based on repetitive DNA fingerprinting analysis, we selected 30 representatives for partial characterization according to their phylogenetic diversity, antimicrobial activities and secondary-metabolite biosynthesis genes. Results from the 16S rRNA gene sequence analysis indicated that the 30 strains could be sorted into 18 phylotypes belonging to 14 different genera: Agrococcus, Arsenicicoccus, Arthrobacter, Brevibacterium, Citricoccus, Janibacter, Kocuria, Microbacterium, Microlunatus, Nocardioides, Nocardiopsis, Saccharopolyspora, Salinibacterium and Streptomyces. To our knowledge, this paper is the first report on the isolation of Microlunatus genus members from marine habitats. Of the 30 isolates, 11 strains exhibited antibacterial and/or antifungal activity, seven of which have activities against Bacillus subtilis and Candida albicans. All 30 strains have at least two biosynthetic genes, one-third of which possess more than four biosynthetic genes. This study demonstrates the significant diversity of Actinobacteria in the Chukchi Shelf sediment and their potential for producing biologically active compounds and novel material for genetic manipulation or combinatorial biosynthesis. PMID:24663116

  6. [In vitro activity of ampicillin-ceftriaxone against Enterococcus faecalis isolates recovered from invasive infections].

    PubMed

    Burguer Moreira, Noelia; Nastro, Marcela; Vay, Carlos; Famiglietti, Ángela; Rodríguez, Carlos Hernán

    2016-01-01

    In vitro activity of the combination of ampicillin- ceftriaxone against 30 Enterococcus faecalis isolates recovered from invasive infections in patients admitted to Hospital de Clínicas José de San Martin in the city of Buenos Aires was assessed. Ampicillin- ceftriaxone synergies were determined by microdilution in Müeller-Hinton (MH) broth with and without subinhibitory concentrations of ceftriaxone. Synergy was detected in 22/30 isolates. A decrease in both minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was observed in 14/30 isolates, whereas in 6/30 isolates the decrease was observed in the MIC value and only in the MBC value in the 2 remaining isolates. The bactericidal activity of the combination showed to be higher at low concentrations of ampicillin (< 1 μg/ml). We detected in vitro synergy using the ampicillin-ceftriaxone combination and thus, its efficacy was confirmed in the treatment of severe infections by E. faecalis.

  7. Draft genome of Bacillus sp. A053 isolated from the Arctic seawater with antimicrobial activity.

    PubMed

    Guo, Wenbin; Chen, Zhiteng; Cui, Pengfei; Chen, Xinhua

    2015-08-01

    Bacillus sp. A053, isolated from the Arctic seawater, shows strong antifungal activity against plant pathogenic fungi. Here, we report the draft sequence of the approximately 4.1-Mbp genome of this strain. To the best of our knowledge, this is the first genome sequence of Bacillus strain isolated from the Arctic seawater with antifungal activity. The genome sequence may provide fundamental molecular information on elucidating the metabolic pathway of antimicrobial compound in this strain.

  8. Finite element code-based modeling of a multi-feature isolation system and passive alleviation of possible inner pounding

    NASA Astrophysics Data System (ADS)

    Ismail, Mohammed; López-Almansa, Francesc; Benavent-Climent, Amadeo; Pujades-Beneit, Luis G.

    2014-09-01

    The existing seismic isolation systems are based on well-known and accepted physical principles, but they are still having some functional drawbacks. As an attempt of improvement, the Roll-N-Cage (RNC) isolator has been recently proposed. It is designed to achieve a balance in controlling isolator displacement demands and structural accelerations. It provides in a single unit all the necessary functions of vertical rigid support, horizontal flexibility with enhanced stability, resistance to low service loads and minor vibration, and hysteretic energy dissipation characteristics. It is characterized by two unique features that are a self-braking (buffer) and a self-recentering mechanism. This paper presents an advanced representation of the main and unique features of the RNC isolator using an available finite element code called SAP2000. The validity of the obtained SAP2000 model is then checked using experimental, numerical and analytical results. Then, the paper investigates the merits and demerits of activating the built-in buffer mechanism on both structural pounding mitigation and isolation efficiency. The paper addresses the problem of passive alleviation of possible inner pounding within the RNC isolator, which may arise due to the activation of its self-braking mechanism under sever excitations such as near-fault earthquakes. The results show that the obtained finite element code-based model can closely match and accurately predict the overall behavior of the RNC isolator with effectively small errors. Moreover, the inherent buffer mechanism of the RNC isolator could mitigate or even eliminate direct structure-to-structure pounding under severe excitation considering limited septation gaps between adjacent structures. In addition, the increase of inherent hysteretic damping of the RNC isolator can efficiently limit its peak displacement together with the severity of the possibly developed inner pounding and, therefore, alleviate or even eliminate the

  9. Magnetic force driven six degree-of-freedom active vibration isolation system using a phase compensated velocity sensor

    SciTech Connect

    Kim, Yongdae; Park, Kyihwan; Kim, Sangyoo

    2009-04-15

    A six-axis active vibration isolation system (AVIS) is developed using voice coil actuators. Point contact configuration is employed to have an easy assembly of eight voice coil actuators to an upper and a base plates. The velocity sensor, using an electromagnetic principle that is commonly used in the vibration control, is investigated since its phase lead characteristic causes an instability problem for a low frequency vibration. The performances of the AVIS are investigated in the frequency domain and finally validated by comparing with the passive isolation system using the atomic force microscope images.

  10. Antioxidant activities of phenolic compounds isolated from the leaves of Macaranga allorobinsonii Whitmore

    NASA Astrophysics Data System (ADS)

    Darmawan, Akhmad; Fajriah, Sofa; Megawati, Dewijanti, Indah D.; Banjarnahor, Sofna; Yuliani, Tri; Hartati, Sri; Mozef, Tjandrawati; Effendi, Ruslan; Swandiny, Greesty F.

    2017-01-01

    Two secondary metabolites compounds, gallic acid (1) and methyl gallate (2) have been isolated from the ethyl acetate fraction of the methanol extract of the leaves of Macaranga allorobinsonii Whitmore. Isolation and purification of the secondary metabolite compounds conducted using chromatography methods, and structure elucidation determined based on NMR, mass spectroscopic data and compared with appropriate references.

  11. Antimicrobial and antileishmanial activities of diterpenoids isolated from the roots of Salvia deserta

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Four diterpenes with biological activity were isolated from Salvia deserta roots. Taxodione was considered leishmanicidal, with IC50 value of 0.46 µg/mL against Leishimania donovani and also exhibited antifungal and antimicrobial activities. Ferruginol displayed the greatest activity (24-h IC50 1.29...

  12. Characterization of Multilayer Piezoelectric Actuators for Use in Active Isolation Mounts

    NASA Technical Reports Server (NTRS)

    Wise, Stephanie A.; Hooker, Matthew W.

    1997-01-01

    Active mounts are desirable for isolating spacecraft science instruments from on-board vibrational sources such as motors and release mechanisms. Such active isolation mounts typically employ multilayer piezoelectric actuators to cancel these vibrational disturbances. The actuators selected for spacecraft systems must consume minimal power while exhibiting displacements of 5 to 10 micron under load. This report describes a study that compares the power consumption, displacement, and load characteristics of four commercially available multilayer piezoelectric actuators. The results of this study indicate that commercially available actuators exist that meet or exceed the design requirements used in spacecraft isolation mounts.

  13. Effect of vertical active vibration isolation on tracking performance and on ride qualities

    NASA Technical Reports Server (NTRS)

    Dimasi, F. P.; Allen, R. E.; Calcaterra, P. C.

    1972-01-01

    An investigation to determine the effect on pilot performance and comfort of an active vibration isolation system for a commercial transport pilot seat is reported. The test setup consisted of: a hydraulic shaker which produced random vertical vibration inputs; the active vibration isolation system; the pilot seat; the pilot control wheel and column; the side-arm controller; and a two-axis compensatory tracking task. The effects of various degrees of pilot isolation on short-term (two-minute) tracking performance and comfort were determined.

  14. In vitro activity of telithromycin against Spanish Streptococcus pneumoniae isolates with characterized macrolide resistance mechanisms.

    PubMed

    Morosini, M I; Cantón, R; Loza, E; Negri, M C; Galán, J C; Almaraz, F; Baquero, F

    2001-09-01

    The susceptibilities to telithromycin of 203 Streptococcus pneumoniae isolates prospectively collected during 1999 and 2000 from 14 different geographical areas in Spain were tested and compared with those to erythromycin A, clindamycin, quinupristin-dalfopristin, penicillin G, cefotaxime, and levofloxacin. Telithromycin was active against 98.9% of isolates (MICs, < or =0.5 microg/ml), with MICs at which 90% of isolates are inhibited being 0.06 microg/ml, irrespective of the resistance genotype. The corresponding values for erythromycin were 61.0% (MICs, < or =0.25 microg/ml) and >64 microg/ml. The erm(B) gene (macrolide-lincosamide-streptogramin B resistance phenotype) was detected in 36.4% (n = 74) of the isolates, which corresponded to 93.6% of erythromycin-intermediate and -resistant isolates, whereas the mef(A) gene (M phenotype [resistance to erythromycin and susceptibility to clindamycin and spiramycin without blunting]) was present in only 2.4% (n = 5) of the isolates. One of the latter isolates also carried erm(B). Interestingly, in one isolate for which the erythromycin MIC was 2 microg/ml, none of these resistance genes could be detected. Erythromycin MICs for S. pneumoniae erm(B)-positive isolates were higher (range, 0.5 to >64 microg/ml) than those for erm(B)- and mef(A)-negative isolates (range, 0.008 to 2 microg/ml). The corresponding values for telithromycin were lower for both groups, with ranges of 0.004 to 1 and 0.002 to 0.06 microg/ml, respectively. The erythromycin MIC was high for a large number of erm(B)-positive isolates, but the telithromycin MIC was low for these isolates. These results indicate the potential usefulness of telithromycin for the treatment of infections caused by erythromycin-susceptible and -resistant S. pneumoniae isolates when macrolides are indicated.

  15. Isolation and Antimicrobial Activity of Flavonoid Compounds from Mahagony Seeds (Swietenia macrophylla, King)

    NASA Astrophysics Data System (ADS)

    Mursiti, S.; Supartono

    2017-02-01

    Flavonoid is one of the secondary metabolites compounds in mahogany seeds. Mahogany seeds can be used as an antimicrobial. This study aims to determine the antimicrobial activity of flavonoid compounds from mahogany seeds against Escherichia coli (E.coli) and Bacillus cereus (B.cereus). Isolation of flavonoid compounds done step by step. First, the maceration using n-hexane, then with methanol. The methanol extract was dissolved in ethyl acetate and aquadest, then separated. Ethyl acetate extract evaporated Flavonoid compounds were. The testing of antimicrobial activity of flavonoid compounds using the absorption method. The results showed that the antimicrobial activity of flavonoid compounds from mahogany seeds shows the inhibitory activity and provide clear zone against bacteria E.coli with value Inhibitory Regional Diameter 18.50 mm respectively, and 14.50 mm to the bacteria. Based on the results of the study, it can be concluded that flavonoid compounds from mahogany seeds have antimicrobial activity against E.coli and B.cereus.

  16. Fructanase and fructosyltransferase activity of non-Saccharomyces yeasts isolated from fermenting musts of Mezcal.

    PubMed

    Arrizon, Javier; Morel, Sandrine; Gschaedler, Anne; Monsan, Pierre

    2012-04-01

    Fructanase and fructosyltransferase are interesting for the tequila process and prebiotics production (functional food industry). In this study, one hundred thirty non-Saccharomyces yeasts isolated from "Mezcal de Oaxaca" were screened for fructanase and fructosyltransferase activity. On solid medium, fifty isolates grew on Agave tequilana fructans (ATF), inulin or levan. In liquid media, inulin and ATF induced fructanase activities of between 0.02 and 0.27U/ml depending of yeast isolate. High fructanase activity on sucrose was observed for Kluyveromyces marxianus and Torulaspora delbrueckii, while the highest fructanase activity on inulin and ATF was observed for Issatchenkia orientalis, Cryptococcus albidus, and Candida apicola. Zygosaccharomyces bisporus and Candida boidinii had a high hydrolytic activity on levan. Sixteen yeasts belonging to K. marxianus, T. delbrueckii and C. apicola species were positive for fructosyltransferase activity. Mezcal microbiota proved to showed to be a source for new fructanase and fructosyltransferases with potential application in the tequila and food industry.

  17. Unique activity spectrum of colicin FY: all 110 characterized Yersinia enterocolitica isolates were colicin FY susceptible.

    PubMed

    Bosák, Juraj; Micenková, Lenka; Vrba, Martin; Ševčíková, Alena; Dědičová, Daniela; Garzetti, Debora; Šmajs, David

    2013-01-01

    Colicin FY is a plasmid encoded toxin that recognizes a yersinia-specific outer membrane protein (YiuR) as a receptor molecule. We have previously shown that the activity spectrum of colicin FY comprises strains of the genus Yersinia. In this study, we analyzed the activity of colicin FY against 110 Yersinia enterocolitica isolates differing in geographical origin and source. All isolates were characterized through analysis of 16S rRNA genes, serotyping, biotyping, restriction profiling of genomic DNA, detection of virulence markers and susceptibility to antibiotics. This confirmed the broad variability of the collection, in which all 110 Y. enterocolitica isolates, representing 77 various strains, were inhibited by colicin FY. Although isolates showed variable levels of susceptibility to colicin FY, it was not associated with any strain characteristic. The universal susceptibility of Y. enterocolitica strains to colicin FY together with the absence of activity towards strains outside the Yersinia genus suggests potential therapeutic applications for colicin FY.

  18. Activity-guided isolation of antioxidants from the leaves of Terminalia arjuna.

    PubMed

    Singh, Pradeep Pratap; Chauhan, S M S

    2014-01-01

    An activity-guided isolation and purification process was used to identify the l,l-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging components of the food plant (Terminalia arjuna) of Antheraea mylitta. Dry leaves of T. arjuna were extracted with different solvents and tested for their antioxidant activity against DPPH(•). The acetone-water (8:2) extract expressed strong DPPH radical-scavenging activity, and was subjected to column chromatography over silica gel. Gallic acid, apigenin, luteolin, quercetin, epicatechin, ellagic acid and 1-O-β-galloyl glucose were isolated as active components and characterised by using different spectroscopic techniques.

  19. Isolation and identification of a cytopathic activity in Tannerella forsythia.

    PubMed

    Nakajima, Takuma; Tomi, Naoko; Fukuyo, Yayoi; Ishikura, Hiroaki; Ohno, Yuka; Arvind, Ramanathan; Arai, Takao; Ishikawa, Isao; Arakawa, Shinichi

    2006-12-08

    Interactions between pathogens and host induce human disorders including periodontitis, disintegration of the tooth supporting tissues. Tannerella forsythia has been linked to the periodontitis and several cytopathic reagents have been found in the bacterium; however, its contribution to the disease remains unclear. Biochemical approach to explore the cytopathic effect revealed two distinct activities in T. forsythia (ATCC 43037) extract; one detaches adherent cells from substratum and another arrests cells at G2. An executor of former activity, forsythia detaching factor (FDF) was identified; its genomic sequence and peptidase activity revealed that FDF is a substantial form of putative PrtH; prtH gene was hypothetically identified directly from a DNA fragment of the bacterium and its native product has never been shown. Since FDF was found in the bacterial culture supernatant, its activity implies a contribution to the disintegration of tissues although the mechanism how FDF disturbs cellular anchors remains elusive.

  20. A New Method for the Isolation of Ergosterol and Peroxyergosterol as Active Compounds of Hygrophoropsis aurantiaca and in Vitro Antiproliferative Activity of Isolated Ergosterol Peroxide.

    PubMed

    Nowak, Renata; Drozd, Marta; Mendyk, Ewaryst; Lemieszek, Marta; Krakowiak, Olga; Kisiel, Wanda; Rzeski, Wojciech; Szewczyk, Katarzyna

    2016-07-21

    In the present study, ergosterol peroxide and ergosterol were isolated for the first time from fresh fruit bodies of Hygrophoropsis aurantiaca (False Chanterelle). The substances were characterized mainly by spectroscopic methods (¹H-NMR, (13)C-NMR, DEPT-45, DEPT-90, DEPT-135, 2D-NMR). In our study, a new specific thin layer chromatographic method was developed for determination of ergosterol and ergosterol peroxide in H. aurantiaca extract. The method is based on the separation of n-hexane extract on silica gel (Silica Gel G) TLC plates using the optimized solvent system toluene/ethyl acetate (3:1; v/v). The main advantages of the developed method are the simplicity of operation and the low cost. The in vitro study results revealed the antiproliferative properties of ergosterol peroxide against LS180 human colon cancer cells. The described effect was attributed both to altered mitochondrial activity and decreased DNA synthesis. Additionally, in the same concentration range the investigated compound was not toxic to CCD 841 CoTr human colon epithelial cells. The present study suggests that fruit bodies of H. aurantiaca have great potential for producing substances and extracts with potential applications in medicine.

  1. Isolation and characterization of genetic variability in bacteria with β-hemolytic and antifungal activity isolated from the rhizosphere of Medicago truncatula plants.

    PubMed

    Hernández-Salmerón, J E; Prieto-Barajas, C M; Valencia-Cantero, E; Moreno-Hagelsieb, G; Santoyo, G

    2014-07-04

    In the present study, we analyzed the frequency of hemolytic and antifungal activities in bacterial isolates from the rhizosphere of Medicago truncatula plants. Of the 2000 bacterial colonies, 96 showed β-hemolytic activities (frequency, 4.8 x 10(-2)). Hemolytic isolates were analyzed for their genetic diversity by using random amplification of polymorphic DNA, yielding 88 haplotypes. The similarity coefficient of Nei and Li showed a polymorphic diversity ranging from 0.3 to 1. Additionally, 8 of the hemolytic isolates showed antifungal activity toward plant pathogens, Diaporthe phaseolorum, Colletotrichum acutatum, Rhizoctonia solani, and Fusarium oxysporum. The 16S ribosomal sequencing analysis showed that antagonistic bacterial isolates corresponded to Bacillus subtilis (UM15, UM33, UM42, UM49, UM52, and UM91), Bacillus pumilus (UM24), and Bacillus licheniformis (UM88). The present results revealed a higher genetic diversity among hemolytic isolates compared to that of isolates with antifungal action.

  2. Isolation, characterization, and biological activity of the Methanococcus thermolithotrophicus ferredoxin.

    PubMed Central

    Hatchikian, E C; Fardeau, M L; Bruschi, M; Belaich, J P; Chapman, A; Cammack, R

    1989-01-01

    A ferredoxin has been isolated from the thermophilic methanogen Methanococcus thermolithotrophicus. The native protein was a monomer exhibiting a molecular weight of 7,262, calculated from the amino acid composition. Its absorption spectrum had two maxima at 390 and 283 nm, with an absorbance ratio A390/A283 of 0.79. The absorption at 390 nm (E = 29 mM-1 cm-1) and the content of iron of the protein are in agreement with the presence of two 4Fe-4S clusters in M. thermolithotrophicus ferredoxin. Its amino acid composition showed the presence of eight cysteine residues, which is the required number of cysteines for the binding of two 4Fe-4S clusters. The protein was characterized by the lack of histidine, arginine, and leucine and a high content of valine. It was unusually stable to high temperatures but not to oxygen. The ESR spectrum of the protein in the oxidized state showed a minor signal at g = 2.01, corresponding to an oxidized 3Fe-4S cluster. The protein, which was difficult to reduce with dithionite or reduced mediators, exhibited in its reduced state a spectrum typical of two interacting reduced 4Fe-4S clusters. M. thermolithotrophicus ferredoxin functioned as an electron acceptor for the CO dehydrogenase complex with an extract free of ferredoxin. No reaction was detected with F420 or hydrogenase. PMID:2540148

  3. Isolation, structures, and structure - cytotoxic activity relationships of withanolides and physalins from Physalis angulata.

    PubMed

    Damu, Amooru G; Kuo, Ping-Chung; Su, Chung-Ren; Kuo, Tsung-Hsiao; Chen, Tzu-Hsuan; Bastow, Kenneth F; Lee, Kuo-Hsiung; Wu, Tian-Shung

    2007-07-01

    Phytochemical investigation of Physalis angulata was initiated following primary biological screening. Fractionation of CHCl3 and n-BuOH solubles of the MeOH extract from the whole plant was guided by in vitro cytotoxic activity assay using cultured HONE-1 and NUGC cells and led to the isolation of seven new withanolides, withangulatins B-H (1-7), and a new minor physalin, physalin W (8), along with 14 known compounds, including physaprun A, withaphysanolide, dihydrowithanolide E, physanolide A, withaphysalin A, and physalins B, D, F, G, I, J, T, U, and V. New compounds (1-8) were fully characterized by a combination of spectroscopic methods (1D and 2D NMR and MS) and the relative stereochemical assignments based on NOESY correlations and analysis of coupling constants. Biological evaluation of these compounds against a panel of human cancer cell lines showed broad cytotoxic activity. Withangulatin B (1) and physalins D (10) and F (11) displayed potent cytotoxic activity against a panel of human cancer cell lines with EC50 values ranging from 0.2 to 1.6 microg/mL. Structure-activity relationship analysis indicated that withanolides and physalins with 4beta-hydroxy-2-en-1-one and 5beta,6beta-epoxy moieties are potential cytotoxic agents.

  4. Active monoterpene ketones isolated from Rosmarinus officinalis with fumigant and contact action against Tyrophagus putrescentiae (Schrank).

    PubMed

    Jeon, Ju-Hyun; Park, Jun-Hwan; Chung, Namhyun; Lee, Hoi-Seon

    2014-08-01

    The acaricidal activities of an active material derived from Rosmarinus officinalis oil and its relative monoterpene ketones were determined using fumigant and contact toxicity bioassays against Tyrophagus putrescentiae and were compared with that of a commercial acaricide (benzyl benzoate). The active component of R. officinalis oil, isolated by silica gel column chromatography and high-performance liquid chromatography, was identified as camphor, based on various spectroscopic analyses. In the fumigant toxicity bioassay, camphor (2.25 μg/cm(3)) was 5.58 times more active than benzyl benzoate (12.56 μg/cm(3)) against T. putrescentiae, followed by (+)-camphor (3.89 μg/cm(3)) and (-)-camphor (5.61 μg/cm(3)). In the contact toxicity bioassay, camphor (1.34 μg/cm(2)) was 6.74 times more toxic than benzyl benzoate (9.03 μg/cm(2)) against T. putrescentiae, followed by (+)-camphor (2.23 μg/cm(2)) and (-)-camphor (2.94 μg/cm(2)). These results indicate that camphor and its derivatives are very useful as potential control agents against stored food mites regardless of the application method.

  5. Probiotic potential of lactobacillus strains isolated from sorghum-based traditional fermented food.

    PubMed

    Rao, K Poornachandra; Chennappa, G; Suraj, U; Nagaraja, H; Raj, A P Charith; Sreenivasa, M Y

    2015-06-01

    Sorghum-based traditional fermented food was screened for potential probiotic lactic acid bacteria. The isolates were identified by biochemical, physiological and genetic methods. Species identification was done by 16s rRNA sequence analysis. The functional probiotic potential of the two Lactobacillus species viz., Lactobacillus plantarum (Lact. plantarum) and Lactobacillus pentosus (Lact. pentosus) was assessed by different standard parameters. The strains were tolerant to pH 2 for 1 h and resistant to methicillin, kanamycin, vancomycin and norfloxacin. Two (Lact. plantarum COORG-3 and Lact. pentosus COORG-8) out of eight isolates recorded the cell surface hydrophobicity to be 59.12 and 64.06%, respectively. All the strains showed tolerance to artificial duodenum juice (pH 2) for 3 h, positive for bile salt hydrolase test and negative for haemolytic test. The neutralized cell-free supernatant of the strains Lact. pentosus COORG-4, Lact. plantarum COORG-1, Lact. plantarum COORG-7, Lact. pentosus COORG-8 and Lact. plantarum COORG-3 showed good antibiofilm activity. Lact. pentosus COORG-8 exhibited 74% activity against Pseudomonas aeruginosa-MTCC 7903 and Lact. plantarum COORG-7 showed 68% inhibition of biofilm against Klebsiella pneumonia MTCC 7407. Three (Lact. plantarum COORG-7, Lact. pentosus COORG-5 and Lact. pentosus COORG 8) out of eight isolates exhibited a good antimicrobial activity against Listeria monocytogenes and five isolates (Lact. pentosus COORG 2, Lact. plantarum COORG 1, Lact. plantarum COORG 4, Lact. pentosus COORG 3 and Lact. plantarum COORG 6) are active against Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Enterobacter aerogenes, Klebsiella pneumonia, Enterococcus faecalis. The study also evaluated the cholesterol lowering property of the Lactobacillus strains using hen egg yolk as the cholesterol source. The cholesterol in hen egg yolk was assimilated by 74.12 and 68.26% by Lact. plantarum COORG 4 and Lact. pentosus COORG 7

  6. Antifungal Activity of Lactic Acid Bacteria Strains Isolated from Natural Honey against Pathogenic Candida Species

    PubMed Central

    Bulgasem, Bulgasem Y.; Lani, Mohd Nizam; Wan Yusoff, Wan Mohtar; Fnaish, Sumaya G.

    2016-01-01

    The role of lactic acid bacteria (LAB) in honey as antifungal activity has received little attention and their mechanism of inhibitory of fungi is not fully understood. In this study, LAB were isolated from honey samples from Malaysia, Libya, Saudi Arabia, and Yemen. Twenty-five isolates were confirmed LAB by catalase test and Gram staining, and were screened for antifungal activity. Four LAB showed inhibitory activity against Candida spp. using the dual agar overlay method. And they were identified as Lactobacillus plantarum HS isolated from Al-Seder honey, Lactobacillus curvatus HH isolated from Al-Hanon honey, Pediococcus acidilactici HC isolated from Tualang honey and Pediococcus pentosaceus HM isolated from Al-Maray honey by the 16S rDNA sequence. The growth of Candida glabrata ATCC 2001 was strongly inhibited (>15.0 mm) and (10~15 mm) by the isolates of L. curvatus HH and P. pentosaceus HM, respectively. The antifungal activity of the crude supernatant (cell free supernatant, CFS) was evaluated using well diffusion method. The CFS showed high antifungal activity against Candida spp. especially The CFS of L. curvatus HH was significantly (p < 0.05) inhibited growth of C. glabrata ATCC 2001, C. parapsilosis ATCC 2201, and C. tropicalis ATCC 750 with inhibitory zone 22.0, 15.6, and 14.7 mm, respectively. While CFS of P. pentosaceus HM was significantly (p < 0.05) effective against C. krusei, C. glabrata, and C. albicans with inhibition zone 17.2, 16.0, and 13.3 mm, respectively. The results indicated that LAB isolated from honey produced compounds which can be used to inhibit the growth of the pathogenic Candida species. PMID:28154488

  7. Antifungal Activity of Lactic Acid Bacteria Strains Isolated from Natural Honey against Pathogenic Candida Species.

    PubMed

    Bulgasem, Bulgasem Y; Lani, Mohd Nizam; Hassan, Zaiton; Wan Yusoff, Wan Mohtar; Fnaish, Sumaya G

    2016-12-01

    The role of lactic acid bacteria (LAB) in honey as antifungal activity has received little attention and their mechanism of inhibitory of fungi is not fully understood. In this study, LAB were isolated from honey samples from Malaysia, Libya, Saudi Arabia, and Yemen. Twenty-five isolates were confirmed LAB by catalase test and Gram staining, and were screened for antifungal activity. Four LAB showed inhibitory activity against Candida spp. using the dual agar overlay method. And they were identified as Lactobacillus plantarum HS isolated from Al-Seder honey, Lactobacillus curvatus HH isolated from Al-Hanon honey, Pediococcus acidilactici HC isolated from Tualang honey and Pediococcus pentosaceus HM isolated from Al-Maray honey by the 16S rDNA sequence. The growth of Candida glabrata ATCC 2001 was strongly inhibited (>15.0 mm) and (10~15 mm) by the isolates of L. curvatus HH and P. pentosaceus HM, respectively. The antifungal activity of the crude supernatant (cell free supernatant, CFS) was evaluated using well diffusion method. The CFS showed high antifungal activity against Candida spp. especially The CFS of L. curvatus HH was significantly (p < 0.05) inhibited growth of C. glabrata ATCC 2001, C. parapsilosis ATCC 2201, and C. tropicalis ATCC 750 with inhibitory zone 22.0, 15.6, and 14.7 mm, respectively. While CFS of P. pentosaceus HM was significantly (p < 0.05) effective against C. krusei, C. glabrata, and C. albicans with inhibition zone 17.2, 16.0, and 13.3 mm, respectively. The results indicated that LAB isolated from honey produced compounds which can be used to inhibit the growth of the pathogenic Candida species.

  8. Isolation and Characterization of Electrochemically Active Subsurface Delftia and Azonexus Species.

    PubMed

    Jangir, Yamini; French, Sarah; Momper, Lily M; Moser, Duane P; Amend, Jan P; El-Naggar, Mohamed Y

    2016-01-01

    Continental subsurface environments can present significant energetic challenges to the resident microorganisms. While these environments are geologically diverse, potentially allowing energy harvesting by microorganisms that catalyze redox reactions, many of the abundant electron donors and acceptors are insoluble and therefore not directly bioavailable. Extracellular electron transfer (EET) is a metabolic strategy that microorganisms can deploy to meet the challenges of interacting with redox-active surfaces. Though mechanistically characterized in a few metal-reducing bacteria, the role, extent, and diversity of EET in subsurface ecosystems remains unclear. Since this process can be mimicked on electrode surfaces, it opens the door to electrochemical techniques to enrich for and quantify the activities of environmental microorganisms in situ. Here, we report the electrochemical enrichment of microorganisms from a deep fractured-rock aquifer in Death Valley, CA, USA. In experiments performed in mesocosms containing a synthetic medium based on aquifer chemistry, four working electrodes (WEs) were poised at different redox potentials (272, 373, 472, 572 mV vs. SHE) to serve as electron acceptors, resulting in anodic currents coupled to the oxidation of acetate during enrichment. The anodes were dominated by Betaproteobacteria from the families Comamonadaceae and Rhodocyclaceae. A representative of each dominant family was subsequently isolated from electrode-associated biomass. The EET abilities of the isolated Delftia strain (designated WE1-13) and Azonexus strain (designated WE2-4) were confirmed in electrochemical reactors using WEs poised at 522 mV vs. SHE. The rise in anodic current upon inoculation was correlated with a modest increase in total protein content. Both genera have been previously observed in mixed communities of microbial fuel cell enrichments, but this is the first direct measurement of their electrochemical activity. While alternate

  9. Characterization of lignocellulolytic activities from fungi isolated from the deep-sea sponge Stelletta normani

    PubMed Central

    Batista-García, Ramón Alberto; Sutton, Thomas; Jackson, Stephen A.; Tovar-Herrera, Omar Eduardo; Balcázar-López, Edgar; Sánchez-Carbente, María del Rayo; Sánchez-Reyes, Ayixon; Dobson, Alan D. W.

    2017-01-01

    Extreme habitats have usually been regarded as a source of microorganisms that possess robust proteins that help enable them to survive in such harsh conditions. The deep sea can be considered an extreme habitat due to low temperatures (<5°C) and high pressure, however marine sponges survive in these habitats. While bacteria derived from deep-sea marine sponges have been studied, much less information is available on fungal biodiversity associated with these sponges. Following screening of fourteen fungi isolated from the deep-sea sponge Stelletta normani sampled at a depth of 751 metres, three halotolerant strains (TS2, TS11 and TS12) were identified which displayed high CMCase and xylanase activities. Molecular based taxonomic approaches identified these strains as Cadophora sp. TS2, Emericellopsis sp. TS11 and Pseudogymnoascus sp. TS 12. These three fungi displayed psychrotolerance and halotolerant growth on CMC and xylan as sole carbon sources, with optimal growth rates at 20°C. They produced CMCase and xylanase activities, which displayed optimal temperature and pH values of between 50–70°C and pH 5–8 respectively, together with good thermostability and halotolerance. In solid-state fermentations TS2, TS11 and TS12 produced CMCases, xylanases and peroxidase/phenol oxidases when grown on corn stover and wheat straw. This is the first time that CMCase, xylanase and peroxidase/phenol oxidase activities have been reported in these three fungal genera isolated from a marine sponge. Given the biochemical characteristics of these ligninolytic enzymes it is likely that they may prove useful in future biomass conversion strategies involving lignocellulosic materials. PMID:28339473

  10. Characterization of lignocellulolytic activities from fungi isolated from the deep-sea sponge Stelletta normani.

    PubMed

    Batista-García, Ramón Alberto; Sutton, Thomas; Jackson, Stephen A; Tovar-Herrera, Omar Eduardo; Balcázar-López, Edgar; Sánchez-Carbente, María Del Rayo; Sánchez-Reyes, Ayixon; Dobson, Alan D W; Folch-Mallol, Jorge Luis

    2017-01-01

    Extreme habitats have usually been regarded as a source of microorganisms that possess robust proteins that help enable them to survive in such harsh conditions. The deep sea can be considered an extreme habitat due to low temperatures (<5°C) and high pressure, however marine sponges survive in these habitats. While bacteria derived from deep-sea marine sponges have been studied, much less information is available on fungal biodiversity associated with these sponges. Following screening of fourteen fungi isolated from the deep-sea sponge Stelletta normani sampled at a depth of 751 metres, three halotolerant strains (TS2, TS11 and TS12) were identified which displayed high CMCase and xylanase activities. Molecular based taxonomic approaches identified these strains as Cadophora sp. TS2, Emericellopsis sp. TS11 and Pseudogymnoascus sp. TS 12. These three fungi displayed psychrotolerance and halotolerant growth on CMC and xylan as sole carbon sources, with optimal growth rates at 20°C. They produced CMCase and xylanase activities, which displayed optimal temperature and pH values of between 50-70°C and pH 5-8 respectively, together with good thermostability and halotolerance. In solid-state fermentations TS2, TS11 and TS12 produced CMCases, xylanases and peroxidase/phenol oxidases when grown on corn stover and wheat straw. This is the first time that CMCase, xylanase and peroxidase/phenol oxidase activities have been reported in these three fungal genera isolated from a marine sponge. Given the biochemical characteristics of these ligninolytic enzymes it is likely that they may prove useful in future biomass conversion strategies involving lignocellulosic materials.

  11. Cytotoxic Activities of Alkylphosphocholines against Clinical Isolates of Acanthamoeba spp.

    PubMed Central

    Walochnik, Julia; Duchêne, Michael; Seifert, Karin; Obwaller, Andreas; Hottkowitz, Thomas; Wiedermann, Gerhard; Eibl, Hansjörg; Aspöck, Horst

    2002-01-01

    Free-living amoebae of the genus Acanthamoeba are causing serious chronic conditions such as destructive keratitis in contact lens wearers or granulomatous amoebic encephalitis in individuals with compromised immune systems. Both are characterized by the lack of availability of sufficiently effective and uncomplicated, manageable treatments. Hexadecylphosphocholine (miltefosine) is licensed for use as a topical antineoplastic agent, but it is also active in vitro against several protozoan parasites, and it was applied very successfully for the treatment of human visceral leishmaniasis. The aim of our study was to evaluate the efficacy of hexadecylphosphocholine and other alkylphosphocholines (APCs) against Acanthamoeba spp. The in vitro activities of eight different APCs against three Acanthamoeba strains of various pathogenicities were determined. All substances showed at least amoebostatic effects, and some of them disrupted the amoebae, as shown by the release of cytoplasmic enzyme activity. Hexadecylphosphocholine exhibited the highest degree of cytotoxicity against trophozoites, resulting in complete cell death at a concentration as low as 40 μM, and also displayed significant cysticidal activity. Hexadecylphosphocholine may be a promising new candidate for the topical treatment of Acanthamoeba keratitis and, conceivably, even for the oral treatment of granulomatous amoebic encephalitis. PMID:11850250

  12. Cytotoxic activities of alkylphosphocholines against clinical isolates of Acanthamoeba spp.

    PubMed

    Walochnik, Julia; Duchêne, Michael; Seifert, Karin; Obwaller, Andreas; Hottkowitz, Thomas; Wiedermann, Gerhard; Eibl, Hansjörg; Aspöck, Horst

    2002-03-01

    Free-living amoebae of the genus Acanthamoeba are causing serious chronic conditions such as destructive keratitis in contact lens wearers or granulomatous amoebic encephalitis in individuals with compromised immune systems. Both are characterized by the lack of availability of sufficiently effective and uncomplicated, manageable treatments. Hexadecylphosphocholine (miltefosine) is licensed for use as a topical antineoplastic agent, but it is also active in vitro against several protozoan parasites, and it was applied very successfully for the treatment of human visceral leishmaniasis. The aim of our study was to evaluate the efficacy of hexadecylphosphocholine and other alkylphosphocholines (APCs) against Acanthamoeba spp. The in vitro activities of eight different APCs against three Acanthamoeba strains of various pathogenicities were determined. All substances showed at least amoebostatic effects, and some of them disrupted the amoebae, as shown by the release of cytoplasmic enzyme activity. Hexadecylphosphocholine exhibited the highest degree of cytotoxicity against trophozoites, resulting in complete cell death at a concentration as low as 40 microM, and also displayed significant cysticidal activity. Hexadecylphosphocholine may be a promising new candidate for the topical treatment of Acanthamoeba keratitis and, conceivably, even for the oral treatment of granulomatous amoebic encephalitis.

  13. RNase One Gene Isolation, Expression, and Affinity Purification Models Research Experimental Progression and Culminates with Guided Inquiry-Based Experiments

    ERIC Educational Resources Information Center

    Bailey, Cheryl P.

    2009-01-01

    This new biochemistry laboratory course moves through a progression of experiments that generates a platform for guided inquiry-based experiments. RNase One gene is isolated from prokaryotic genomic DNA, expressed as a tagged protein, affinity purified, and tested for activity and substrate specificity. Student pairs present detailed explanations…

  14. Antifungal Activity of Bee Venom and Sweet Bee Venom against Clinically Isolated Candida albicans

    PubMed Central

    Lee, Seung-Bae

    2016-01-01

    Objectives: The purpose of this study was to investigate the antifungal effect of bee venom (BV) and sweet bee venom (SBV) against Candida albicans (C. albicans) clinical isolates. Methods: In this study, BV and SBV were examined for antifungal activities against the Korean Collection for Type Cultures (KCTC) strain and 10 clinical isolates of C. albicans. The disk diffusion method was used to measure the antifungal activity and minimum inhibitory concentration (MIC) assays were performed by using a broth microdilution method. Also, a killing curve assay was conducted to investigate the kinetics of the anti- fungal action. Results: BV and SBV showed antifungal activity against 10 clinical isolates of C. albicans that were cultured from blood and the vagina by using disk diffusion method. The MIC values obtained for clinical isolates by using the broth microdilution method varied from 62.5 μg/ mL to 125 μg/mL for BV and from 15.63 μg/mL to 62.5 μg/mL for SBV. In the killing-curve assay, SBV behaved as amphotericin B, which was used as positive control, did. The antifungal efficacy of SBV was much higher than that of BV. Conclusion: BV and SBV showed antifungal activity against C. albicans clinical strains that were isolated from blood and the vagina. Especially, SBV might be a candidate for a new antifungal agent against C. albicans clinical isolates. PMID:27280049

  15. Plant oligoadenylates: enzymatic synthesis, isolation, and biological activities

    SciTech Connect

    Devash, Y.; Reichman, M.; Sela, I.; Reichenbach, N.L.; Suhadolnik, R.J.

    1985-01-29

    An enzyme that converts (/sup 3/H, /sup 32/P)ATP, with a /sup 3/H:/sup 32/P ratio of 1:1, to oligoadenylates with the same /sup 3/H:/sup 32/P ratio was increased in plants following treatment with human leukocyte interferon or plant antiviral factor or inoculation with tobacco mosaic virus. The enzyme was extracted from tobacco leaves, callus tissue cultures, or cell suspension cultures. The enzyme, a putative plant oligoadenylate synthetase, was immobilized on poly(rI) . poly(rC)-agarose columns and converted ATP into plant oligoadenylates. These oligoadenylates were displaced from DEAE-cellulose columns with 350 mM KCl buffer, dialyzed, and further purified by high-performance liquid chromatography (HPLC) and DEAE-cellulose gradient chromatography. In all steps of purification, the ratio of /sup 3/H:/sup 32/P in the oligoadenylates remained 1:1. The plant oligoadenylates isolated by displacement with 350 mM KCl had a molecular weight greater than 1000. The plant oligoadenylates had charges of 5- and 6-. HPLC resolved five peaks, three of which inhibited protein synthesis in reticulocyte and wheat germ systems. Partial structural elucidation of the plant oligoadenylates has been determined by enzymatic and chemical treatments. An adenylate with a 3',5'-phosphodiester and/or a pyrophosphoryl linkage with either 3'- or 5'-terminal phosphates is postulated on the basis of treatment of the oligoadenylates with T2 RNase, snake venom phosphodiesterase, and bacterial alkaline phosphatase and acid and alkaline hydrolyses. The plant oligoadenylates at 8 X 10(-7) M inhibit protein synthesis by 75% in lysates from rabbit reticulocytes and 45% in wheat germ cell-free systems.

  16. Plant oligoadenylates: enzymatic synthesis, isolation, and biological activities.

    PubMed

    Devash, Y; Reichman, M; Sela, I; Reichenbach, N L; Suhadolnik, R J

    1985-01-29

    An enzyme that converts [3H, 32P]ATP, with a 3H:32P ratio of 1:1, to oligoadenylates with the same 3H:32P ratio was increased in plants following treatment with human leukocyte interferon or plant antiviral factor or inoculation with tobacco mosaic virus. The enzyme was extracted from tobacco leaves, callus tissue cultures, or cell suspension cultures. The enzyme, a putative plant oligoadenylate synthetase, was immobilized on poly(rI) . poly(rC)-agarose columns and converted ATP into plant oligoadenylates. These oligoadenylates were displaced from DEAE-cellulose columns with 350 mM KCl buffer, dialyzed, and further purified by high-performance liquid chromatography (HPLC) and DEAE-cellulose gradient chromatography. In all steps of purification, the ratio of 3H:32P in the oligoadenylates remained 1:1. The plant oligoadenylates isolated by displacement with 350 mM KCl had a molecular weight greater than 1000. The plant oligoadenylates had charges of 5- and 6-. HPLC resolved five peaks, three of which inhibited protein synthesis in reticulocyte and wheat germ systems. Partial structural elucidation of the plant oligoadenylates has been determined by enzymatic and chemical treatments. An adenylate with a 3',5'-phosphodiester and/or a pyrophosphoryl linkage with either 3'- or 5'-terminal phosphates is postulated on the basis of treatment of the oligoadenylates with T2 RNase, snake venom phosphodiesterase, and bacterial alkaline phosphatase and acid and alkaline hydrolyses. The plant oligoadenylates at 8 X 10(-7) M inhibit protein synthesis by 75% in lysates from rabbit reticulocytes and 45% in wheat germ cell-free systems.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Production of anti-methicillin-resistant Staphylococcus activity from Bacillus subtilis sp. strain B38 newly isolated from soil.

    PubMed

    Tabbene, Olfa; Ben Slimene, Imen; Bouabdallah, Faten; Mangoni, Maria-Luisa; Urdaci, Maria-Camino; Limam, Ferid

    2009-06-01

    B38 bacterial strain, isolated from Tunisian soil showed a strong antimicrobial activity. Based on biochemical characterization and 16S rDNA sequence analysis, B38 strain was identified as Bacillus subtilis. Cell culture supernatant showed antibacterial activity against clinical isolates of methicillin-resistant Staphylococcus species and several Gram-positive and Gram-negative bacteria. Antifungal activity against phytopathogenic fungi was also observed. Antibacterial activity production started at early exponential growth phase, and maximum activity was reached at the stationary phase. This antibacterial activity was neither affected by proteases, lipase, and organic solvents, nor by surfactants. It was stable over a wide pH range and still active after autoclaving at 121 degrees C during 20 min. Thin layer chromatography followed by bioautography assay allowed the detection of four active spots with R(f) values of 0.30, 0.47, 0.70, and 0.82. The single spot with R (f) 0.30 showed antifungal activity, whereas the spots with R(f) values of 0.47, 0.70, and 0.82 exhibited antibacterial activity.

  18. Taonella mepensis gen. nov., sp. nov., a member of the family Rhodospirillaceae isolated from activated sludge.

    PubMed

    Xi, Xue-dong; Dong, Wei-liang; Zhang, Jun; Huang, Yan; Cui, Zhong-li

    2013-07-01

    A novel Gram-negative, non-spore-forming, rod-shaped strain, H1(T), was isolated from activated sludge by micromanipulation. No close relatives among cultured bacterial isolates were found; phylogenetic analysis based on 16S rRNA gene sequences revealed that strain H1(T) forms a deep single branch in the family Rhodospirillaceae. Cells of strain H1(T) were slightly curved to straight rods (1.2-1.4 × 1.5-1.7 µm) and motile by a single polar flagellum. Strain H1(T) was able to grow in the presence of 0-4 % NaCl and grew optimally at 37 °C and pH 6.0-7.0. Chemotaxonomic analysis revealed that strain H1(T) possessed Q-10 as the predominant ubiquinone and C18 : 1ω7c, C16 : 0 and C19 : 0 cyclo ω8c as the major fatty acids. The DNA G+C content of strain H1(T) was 65.1 mol%. Comparative analysis of 16S rRNA gene sequences, and phenotypic and chemotaxonomic data, indicate that strain H1(T) should represent a novel genus and species of the family Rhodospirillaceae. The name Taonella mepensis gen. nov., sp. nov. is proposed. The type strain of Taonella mepensis is H1(T) ( = CICC 10529(T) = CCTCC AB 2012861(T) = KACC 16940(T)).

  19. Evaluation of cytotoxic and anti-tumor activity of partially purified serine protease isolate from the Indian earthworm Pheretima posthuma

    PubMed Central

    Verma, Mahendra Kumar; Xavier, Francies; Verma, Yogendra Kumar; Sobha, Kota

    2013-01-01

    Objective To isolate, partially purify and evaluate the cytotoxic and antitumor activity of a serine protease from the chosen Indian earthworm Pheretima posthuma. Methods Whole animal extract was prepared and purified its protein constituents by size and charge based chromatographic separation techniques using Sephadex G-50 and DEAE-Cellulose resin respectively. Average molecular weight of the protein isolate was determined and analyzed for its cytotoxic property against Vero cells in different dilutions (1: 20 and 1: 40) and anti-tumor activity by MTT assay (a colorimetric assay) using breast cancer cell line MCF-7, with tamoxifen as standard. Results One of the protein constituents after purification was characterized as serine protease by Caseinolytic plate diffusion assay. Average molecular weight of this purified isolate was determined, by SDS-PAGE analysis with standard protein ladder, as of 15 kDa. The performed tests suggested that the 15kDa fraction has potent cytotoxic activity and satisfactory antitumor activity as well in vitro. Conclusions Exact molecular mechanism of the cytotoxic and antitumor activities is yet to be explored and currently we are working on ultra-purification and biophysical characterization of this fraction. Further investigation into the mechanism(s) of cytotoxic and antitumor activities at molecular level would be useful in treatment of various classes of cancer and viral infections in future.

  20. Identification and Antibacterial Activity of Bacteria Isolated from Marine Sponge Haliclona (Reniera) sp. against Multi-Drug Resistant Human Pathogen

    NASA Astrophysics Data System (ADS)

    Ardhanu Asagabaldan, Meezan; Ayuningrum, D.; Kristiana, R.; Sabdono, A.; Radjasa, O. K.; Trianto, A.

    2017-02-01

    The marine sponge Haliclona (Reniera) sp. was a potential source of natural bioactive compounds. This sponge widely distributed along the coast of Panjang Island, Jepara, Indonesia. The aims of this research were to isolate the associated bacteria with Haliclona (Reniera) sp. and to screen the antibacterial activity against Multi-Drug Resistant (MDR) bacteria. Amount five bacteria were isolated using media selective for bacteria. The antibacterial activities of bacteria were performed by overlay methods. The bacteria strain PSP. 39-04 had the best activity against Pseudomonas aeruginosa, Staphylococcus aureus, Acinetobacter baumannii, and Enterobacter cloaceae. Based on colony morphology and phylogenetic characterization using 16S rRNA gene sequencing, PSP 39-04 was closely related with Chromohalobacter salixigens strain DSM3043.

  1. Activities of Therapeutic Agents and Myristamidopropyl Dimethylamine against Acanthamoeba Isolates

    PubMed Central

    Kilvington, Simon; Hughes, Reanne; Byas, James; Dart, John

    2002-01-01

    The activities of therapeutic agents and myristamidopropyl dimethylamine (MAPD) against Acanthamoeba strains recalcitrant to medical therapy were studied. MAPD minimum cysticidal concentrations were 6.25 to 25 μg/ml; 10 to 30 μg/ml gave at least a 3-log cyst kill after 6 h, and 50 and 100 μg/ml gave at least a 3-log cyst kill within 2 and 1 h, respectively. PMID:12019127

  2. Activities of therapeutic agents and myristamidopropyl dimethylamine against Acanthamoeba isolates.

    PubMed

    Kilvington, Simon; Hughes, Reanne; Byas, James; Dart, John

    2002-06-01

    The activities of therapeutic agents and myristamidopropyl dimethylamine (MAPD) against Acanthamoeba strains recalcitrant to medical therapy were studied. MAPD minimum cysticidal concentrations were 6.25 to 25 microg/ml; 10 to 30 microg/ml gave at least a 3-log cyst kill after 6 h, and 50 and 100 microg/ml gave at least a 3-log cyst kill within 2 and 1 h, respectively.

  3. Endophytic Fungi Isolated from Coleus amboinicus Lour Exhibited Antimicrobial Activity

    PubMed Central

    Astuti, Puji; Sudarsono, Sudarsono; Nisak, Khoirun; Nugroho, Giri Wisnu

    2014-01-01

    Purpose: Coleus amboinicus is a medicinal plant traditionally used to treat various diseases such as throat infection, cough and fever, diarrhea, nasal congestion and digestive problems. The plant was explored for endophytic fungi producing antimicrobial agents. Methods: Screening for endophytic fungi producing antimicrobial agents was conducted using agar plug method and antimicrobial activity of promising ethyl acetate extracts was determined by disc diffusion assay. Thin layer chromatography (TLC) - bioautography was performed to localize the bioactive components within the extract. TLC visualization detection reagents were used to preliminary analyze phytochemical groups of the bioactive compounds. Results: Three endophytic fungi were obtained, two of them showed promising potential. Agar diffusion method showed that endophytic fungi CAL-2 exhibited antimicrobial activity against P. aeruginosa, B. subtilis, S. aureus and S. thypi, whilst CAS-1 inhibited the growth of B. subtilis. TLC bioautography of ethyl acetate extract of CAL-2 revealed at least three bands exhibited antimicrobial activity and at least two bands showed inhibition of B. subtilis growth. Preliminary analysis of the crude extracts suggests that bioactive compounds within CAL-2 extract are terpenoids, phenolics and phenyl propanoid compounds whilst the antimicrobial agents within CAS-1 extract are terpenoids, propylpropanoids, alkaloids or heterocyclic nitrogen compounds. Conclusion: These data suggest the potential of endophytic fungi of C. amboinicus as source for antimicrobial agents. PMID:25671195

  4. Isolation, characterization and antioxidant activity of polysaccharide from Schisandra sphenanthera.

    PubMed

    Zhao, Ting; Mao, Guanghua; Feng, Weiwei; Mao, Riwen; Gu, Xiaoyun; Li, Ting; Li, Qian; Bao, Yongtuan; Yang, Liuqing; Wu, Xiangyang

    2014-05-25

    A water-soluble polysaccharide (SSPP11) from Schisandra sphenanthera was purified by DEAE-cellulose and Sephadex G-100 columns. Structure of SSPP11 and its antioxidant activity was evaluated. Results showed that SSPP11 has a molecular weight of 5.3×10(3)Da and is composed of Man, Glu and Gal. A linkage analysis and NMR study revealed that SSPP11 has a backbone of →1)-d-Man-(6→, →1)-d-Manp-(2→, →1)-d-Glup(4→, →1)-d-Glup-(6→, →1)-d-Galp-(4→, →1)-d-Galp-(4,6→ and →1)-d-Manp-(3,6→, with Man, Glu and Gal, which are distributed in branched chains. The Congo red absorption test revealed that SSPP11 has a triple helix stereo-configuration. Moreover, antioxidant activity of SSPP11 was stronger than the polysaccharide from Schisandra chinensis (Turcz.) Baill. In sum, this study demonstrates that a moderate molecular weight, triple helix stereo-configuration and higher degree of branching are beneficial for exerting antioxidant activity.

  5. A review on antifungal activity of mushroom (basidiomycetes) extracts and isolated compounds.

    PubMed

    Alves, Maria José; Ferreira, Isabel C F R; Dias, Joana; Teixeira, Vânia; Martins, Anabela; Pintado, Manuela

    2013-01-01

    The present review reports the antifungal activity of mushroom extracts and isolated compounds including high (e.g. peptides and proteins) and low (e.g. sesquiterpenes and other terpenes, steroids, organic acids, acylcyclopentenediones and quinolines) molecular weight compounds. Most of the studies available on literature focused on screening of antifungal activity of mushroom extracts, rather than of isolated compounds. Data indicate that mushroom extracts are mainly tested against different Candida species, while mushroom compounds are mostly tested upon other fungi. Therefore, the potential of these compounds might be more useful in food industry than in clinics. Oudemansiella canarii and Agaricus bisporus methanolic extracts proved to be the most active mushroom extracts against Candida spp. Grifolin, isolated from Albatrellus dispansus, seemed to be the most active compound against phytopathogenic fungi. Further studies should be performed in order to better understand the mechanism of action of this and other antifungal compounds as well as safety issues.

  6. Diversity and extracellular enzymatic activities of yeasts isolated from King George Island, the sub-Antarctic region

    PubMed Central

    2012-01-01

    Background Antarctica has been successfully colonized by microorganisms despite presenting adverse conditions for life such as low temperatures, high solar radiation, low nutrient availability and dryness. Although these “cold-loving” microorganisms are recognized as primarily responsible for nutrient and organic matter recycling/mineralization, the yeasts, in particular, remain poorly characterized and understood. The aim of this work was to study the yeast microbiota in soil and water samples collected on King George Island. Results A high number of yeast isolates was obtained from 34 soil and 14 water samples. Molecular analyses based on rDNA sequences revealed 22 yeast species belonging to 12 genera, with Mrakia and Cryptococcus genera containing the highest species diversity. The species Sporidiobolus salmonicolor was by far the most ubiquitous, being identified in 24 isolates from 13 different samples. Most of the yeasts were psychrotolerant and ranged widely in their ability to assimilate carbon sources (consuming from 1 to 27 of the 29 carbon sources tested). All species displayed at least 1 of the 8 extracellular enzyme activities tested. Lipase, amylase and esterase activity dominated, while chitinase and xylanase were less common. Two yeasts identified as Leuconeurospora sp. and Dioszegia fristingensis displayed 6 enzyme activities. Conclusions A high diversity of yeasts was isolated in this work including undescribed species and species not previously isolated from the Antarctic region, including Wickerhamomyces anomalus, which has not been isolated from cold regions in general. The diversity of extracellular enzyme activities, and hence the variety of compounds that the yeasts may degrade or transform, suggests an important nutrient recycling role of microorganisms in this region. These yeasts are of potential use in industrial applications requiring high enzyme activities at low temperatures. PMID:23131126

  7. Note: A three-dimension active vibration isolator for precision atom gravimeters

    SciTech Connect

    Zhou, Min-Kang; Xiong, Xin; Chen, Le-Le; Cui, Jia-Feng; Duan, Xiao-Chun; Hu, Zhong-Kun

    2015-04-15

    An ultra-low frequency active vibration isolator, simultaneously suppressing three-dimensional vibration noise, is demonstrated experimentally. The equivalent natural period of the isolator is 100 s and 12 s for the vertical and horizontal direction, respectively. The vibration noise in the vertical direction is about 50 times reduced during 0.2 and 2 Hz, and 5 times reduced in the other two orthogonal directions in the same frequency range. This isolator is designed for atom gravimeters, especially suitable for the gravimeter whose sensitivity is limited by vibration couplings.

  8. Bactericidal activity of black pepper, bay leaf, aniseed and coriander against oral isolates.

    PubMed

    Chaudhry, Nazia Masood Ahmed; Tariq, Perween

    2006-07-01

    Present investigation focused on antibacterial potential of aqueous decoction of black pepper (Piper nigrum L.), bay leaf (Laurus nobilis L.), aniseed (Pimpinella anisum L.), and coriander (Coriandum sativum L.) against 176 bacterial isolates belonging to 12 different genera of bacterial population isolated from oral cavity of 200 individuals. The disc diffusion technique was employed. Overall aqueous decoction of black pepper was the most bacterial-toxic exhibited 75% antibacterial activity as compared to aqueous decoction of bay leaf (53.4%) and aqueous decoction of aniseed (18.1%), at the concentration of 10 ml/disc. The aqueous decoction of coriander did not show any antibacterial effect against tested bacterial isolates.

  9. Anti-inflammatory activity of constituents isolated from Terminalia chebula ***waiting for publication date

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was aimed at the evaluation of the anti-inflammatory activity of twelve compounds isolated from the methanolic extract of fruits of Terminalia chebula. The activity was determined in terms of their ability to inhibit inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in L...

  10. Antimicrobial activity of coupled hydroxyanthracenones isolated from plants of the genus Karwinskia.

    PubMed

    Salazar, Ricardo; Rivas, Verónica; González, Gloria; Waksman, Noemí

    2006-07-01

    The in vitro activity of some isolated hydroxyanthracenones belonging to the genus Karwinskia against four bacteria, six filamentous fungi and four yeast are reported. These hydroxyanthracenones were found to possess antimicrobial activity, particularly against Streptococcus pyogenes, Candida albicans, C. boidinii, C. glabrata and Cryptococcus neoformans; minimal inhibitory concentrations range between 16 and 2 microg/ml.

  11. Centrifugal precipitation chromatography, a powerful technique for the isolation of active enzymes from tea leaves (Camellia sinensis).

    PubMed

    Baldermann, Susanne; Fleischmann, Peter; Bolten, Mareike; Watanabe, Naoharu; Winterhalter, Peter; Ito, Yoichiro

    2009-05-08

    Centrifugal precipitation chromatography was developed approximately 10 years ago. In contrast to other counter-current chromatographic techniques, the centrifugal precipitation chromatography system is operated with two mutually miscible solutions separated by a cut-off membrane. Centrifugal precipitation chromatography was firstly introduced for the separation of proteins using an ammonium sulfate gradient. In this study we describe a novel approach using solvent-based protein precipitation for the isolation of active plant enzymes from tea leaves (Camellia sinensis) by centrifugal precipitation chromatography. We developed a gradient based on acetone and Tris-buffer, because the biological activity of carotenases in tea leaves cannot be preserved in the presence of ammonium sulfate. Parameters such as the critical solvent concentration, flow rate, buffer concentration, and sample load were determined and/or optimized. Subsequently, the newly developed separation protocol was successfully used for the isolation of active carotenoid cleavage enzymes from tea leaves. The isolated enzymes showed high enzymatic activities and purities and could be directly used for enzymatic assays and structure elucidation.

  12. Iridoid glycosides isolated from Scrophularia dentata Royle ex Benth. and their anti-inflammatory activity.

    PubMed

    Zhang, Liuqiang; Zhu, Tiantian; Qian, Fei; Xu, Jinwen; Dorje, Gaawe; Zhao, Zhili; Guo, Fujiang; Li, Yiming

    2014-10-01

    Scrodentosides A-E (1-5), five new acylated iridoid glycosides, together with 19 known ones, were isolated from the whole plant of Scrophularia dentata Royle ex Benth. The structures of these isolated glycosides were elucidated by spectroscopic methods. Bioassay showed that compounds 7 and 11 had significant inhibitory effect against NF-κB activation with IC50 value of 43.7 μM and 1.02 μM respectively.

  13. Isolation of cell type-specific apoptotic bodies by fluorescence-activated cell sorting

    PubMed Central

    Atkin-Smith, Georgia K.; Paone, Stephanie; Zanker, Damien J.; Duan, Mubing; Phan, Than K.; Chen, Weisan; Hulett, Mark D.; Poon, Ivan K. H.

    2017-01-01

    Apoptotic bodies (ApoBDs) are membrane-bound extracellular vesicles that can mediate intercellular communication in physiological and pathological settings. By combining recently developed analytical strategies with fluorescence-activated cell sorting (FACS), we have developed a method that enables the isolation of ApoBDs from cultured cells to 99% purity. In addition, this approach also enables the identification and isolation of cell type-specific ApoBDs from tissue, bodily fluid and blood-derived samples. PMID:28057919

  14. Killer activity of yeasts isolated from natural environments against some medically important Candida species.

    PubMed

    Vadkertiová, Renata; Sláviková, Elena

    2007-01-01

    Twenty-five yeast cultures, mainly of human origin, belonging to four pathogenic yeast species--Candida albicans, Candida krusei, Candida parapsilosis, and Candida tropicalis were tested for their sensitivity to ten basidiomycetous and eleven ascomycetous yeast species isolated from the water and soil environments and from tree leaves. The best killer activity among basidiomycetous species was exhibited by Rhodotorula glutinis, and R. mucilaginosa. The other carotenoid producing species Cystofilobasidium capitatum, Sporobolomyces salmonicolor, and S. roseus were active only against about 40% of the tested strains and exhibited weak activity. The broadest killer activity among ascomycetous yeasts was shown by the strains Pichia anomala and Metschnikowia pulcherrima. The species Debaryomyces castellii, Debaryomyces hansenii, Hanseniaspora guilliermondii, Pichia membranifaciens, and Williopsis californica did not show any killer activity. The best killer activity exhibited the strains isolated from leafy material. The lowest activity pattern was found among strains originating from soil environment.

  15. Optical isolator based on mode conversion in magnetic garnet films.

    PubMed

    Hemme, H; Dötsch, H; Menzler, H P

    1987-09-15

    Calculations are presented describing a novel optical isolator which works by complete TE(0)-TM(0) mode conversion in magnetic garnet films caused by stress-induced optical anisotropy (50%) and by Faraday rotation (50%). These conversions take place along two different, perpendicular light paths in the same crystal that are connected by an integrated mirror. Possible tolerances of the film parameters are given so that a 30-dB isolation is still guaranteed.

  16. Investigation of the Antimicrobial Activity of Bacillus licheniformis Strains Isolated from Retail Powdered Infant Milk Formulae.

    PubMed

    Alvarez-Ordóñez, Avelino; Begley, Máire; Clifford, Tanya; Deasy, Thérèse; Considine, Kiera; O'Connor, Paula; Ross, R Paul; Hill, Colin

    2014-03-01

    This study investigated the potential antimicrobial activity of ten Bacillus licheniformis strains isolated from retail infant milk formulae against a range of indicator (Lactococcus lactis, Lactobacillus bulgaricus and Listeria innocua) and clinically relevant (Listeria monocytogenes, Staphylococcus aureus, Streptococcus agalactiae, Salmonella Typhimurium and Escherichia coli) microorganisms. Deferred antagonism assays confirmed that all B. licheniformis isolates show antimicrobial activity against the Gram-positive target organisms. PCR and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analyses indicated that four of the B. licheniformis isolates produce the bacteriocin lichenicidin. The remaining six isolates demonstrated a higher antimicrobial potency than lichenicidin-producing strains. Further analyses identified a peptide of ~1,422 Da as the most likely bioactive responsible for the antibacterial activity of these six isolates. N-terminal sequencing of the ~1,422 Da peptide from one strain identified it as ILPEITXIFHD. This peptide shows a high homology to the non-ribosomal peptides bacitracin and subpeptin, known to be produced by Bacillus spp. Subsequent PCR analyses demonstrated that the six B. licheniformis isolates may harbor the genetic machinery needed for the synthesis of a non-ribosomal peptide synthetase similar to those involved in production of subpeptin and bacitracin, which suggests that the ~1,422 Da peptide might be a variant of subpeptin and bacitracin.

  17. Terahertz isolator based on nonreciprocal magneto-metasurface.

    PubMed

    Chen, Sai; Fan, Fei; Wang, Xianghui; Wu, Pengfei; Zhang, Hui; Chang, Shengjiang

    2015-01-26

    A magneto-metasurface with nonreciprocal terahertz (THz) transmission has been proposed to form a THz isolator. Importantly, we have discussed the two necessary conditions for THz nonreciprocal transmission in the metasurface: (1) There should be magneto-optical responses for THz waves in the metasurface; (2) The transmission system of the metasurface needs to be asymmetric for forward and backward waves. These two conditions lead to the time reversal symmetry breaking of system, and the magnetoplasmon mode splitting and nonreciprocal resonance enhancement can be observed in the asymmetry magneto-metasurface. Moreover, the isolation dependences and tunability on the external magnetic field and temperature have also been investigated, which shows that the best operating state with a high isolation can be designed. The numerical simulations show a maximum isolation of 43 dB and a 10 dB operating bandwidth of 20 GHz under an external magnetic field of 0.3 T, and the insertion loss is smaller than 1.79 dB. This low-loss, high isolation, easy coupling THz isolator has broadly potentials for THz application systems.

  18. Macrophage immunomodulatory activity of polysaccharides isolated from Opuntia polyacantha

    PubMed Central

    Schepetkin, Igor A.; Xie, Gang; Kirpotina, Liliya N.; Klein, Robyn A.; Jutila, Mark A.; Quinn, Mark T.

    2008-01-01

    Opuntia polyacantha (prickly pear cactus) has been used extensively for its nutritional properties; however, less is known regarding medicinal properties of Opuntia tissues. In the present study, we extracted polysaccharides from O. polyacantha and used size-exclusion chromatography to fractionate the crude polysaccharides into four polysaccharide fractions (designated as Opuntia polysaccharides C-I to C-IV). The average Mr of fractions C-I through C-IV was estimated to be 733, 550, 310, and 168 kDa, respectively, and sugar composition analysis revealed that Opuntia polysaccharides consisted primarily of galactose, galacturonic acid, xylose, arabinose, and rhamnose. Analysis of the effects of Opuntia polysaccharides on human and murine macrophages demonstrated that all four fractions had potent immunomodulatory activity, inducing production of reactive oxygen species, nitric oxide, tumor necrosis factor α, and interleukin 6. Furthermore, modulation of macrophage function by Opuntia polysaccharides was mediated, at least in part, through activation of nuclear factor κB. Together, our results provide a molecular basis to explain a portion of the beneficial therapeutic properties of extracts from O. polyacantha and support the concept of using Opuntia polysaccharides as an immunotherapeutic adjuvant. PMID:18597716

  19. Active hydrogen excretion and sodium absorption through isolated frog skin.

    PubMed

    Ehrenfeld, J; Garcia-Romeu, F

    1977-07-01

    The in vitro skin of Rana esculenta was studied in open-circuit conditions. It was shown that when the external face is bathed in a 2-meq solution of NaCl, sodium is absorbed at a significantly higher rate than chloride. The ionic balance is maintained by excretion of hydrogen. With a mucosal solution of 2 meq Na2SO4 the equation relating sodium absorption to proton excretion is JnH+ = (-25 +/- 7) - (0.73 +/- 0.04) JnNa+. The correlation between the two variables is highly significant. Hydrogen excretion obeys saturation kinetics in relation to the sodium concentration of the mucosal solution. Maximum excretion occurs at a sodium concentration of 4 meq. When the mucosal solution is a 115-meq solution of Na2SO4 the net flux of sodium is 2.3 times higher than that of hydrogen. The balance is maintained by absorption of SO42-. The effects of various substances on the Na+ext/H+int exchange were studied. With a mucosal solution of 2 meq Na2SO4 and short-circuit conditions it was shown that the hydrogen excretion is active and nearly the same as in open circuit, the short-circuit current is equal (to within 8%) to the sum of the sodium and hydrogen net fluxes, and the correlation between the movements of the two ions is low. A model relating the active proton excretion with the sodium transport mechanism is proposed.

  20. Macrophage immunomodulatory activity of polysaccharides isolated from Opuntia polyacantha.

    PubMed

    Schepetkin, Igor A; Xie, Gang; Kirpotina, Liliya N; Klein, Robyn A; Jutila, Mark A; Quinn, Mark T

    2008-10-01

    Opuntia polyacantha (prickly pear cactus) has been used extensively for its nutritional properties; however, less is known regarding medicinal properties of Opuntia tissues. In the present study, we extracted polysaccharides from O. polyacantha and used size-exclusion chromatography to fractionate the crude polysaccharides into four polysaccharide fractions (designated as Opuntia polysaccharides C-I to C-IV). The average M(r) of fractions C-I through C-IV was estimated to be 733, 550, 310, and 168 kDa, respectively, and sugar composition analysis revealed that Opuntia polysaccharides consisted primarily of galactose, galacturonic acid, xylose, arabinose, and rhamnose. Analysis of the effects of Opuntia polysaccharides on human and murine macrophages demonstrated that all four fractions had potent immunomodulatory activity, inducing production of reactive oxygen species, nitric oxide, tumor necrosis factor alpha, and interleukin 6. Furthermore, modulation of macrophage function by Opuntia polysaccharides was mediated, at least in part, through activation of nuclear factor kappaB. Together, our results provide a molecular basis to explain a portion of the beneficial therapeutic properties of extracts from O. polyacantha and support the concept of using Opuntia polysaccharides as an immunotherapeutic adjuvant.

  1. Antimicrobial Activity of Solithromycin against Clinical Isolates of Legionella pneumophila Serogroup 1

    PubMed Central

    Mallegol, Julia; Fernandes, Prabhavathi

    2014-01-01

    The activity of solithromycin was evaluated against clinical Legionella pneumophila serogroup 1 (Lp1) isolates (n = 196) collected in Ontario, Canada, from 1980 to 2011. Its in vitro activity was compared to that of azithromycin (AZM) using the broth microdilution method. Solithromycin had a MIC50 of ≤0.015 μg/ml and a MIC90 of 0.031 μg/ml, making its activity at least 8-fold to 32-fold higher than that of AZM (MIC50 and MIC90, 0.125 μg/ml and 1 μg/ml, respectively). Ninety-nine percent of the isolates had MICs for solithromycin ranging from ≤0.015 μg/ml to 0.031 μg/ml, whereas 83.6% of the isolates showed MICs for AZM ranging from 0.062 μg/ml to 0.25 μg/ml. Interestingly, 96.7% (30 out of 31 clinical isolates) identified with higher AZM MICs (0.5 μg/ml to 2 μg/ml) belonged to the clinically prevalent sequence type 1. To investigate the intracellular activity of solithromycin, in vitro invasion assays were also performed against a subset of representative Lp1 isolates internalized within human lung epithelial cells. Solithromycin and AZM both inhibited growth of all intracellular Lp1 isolates at 1× or 8× MICs, displaying bacteriostatic effects, as would be expected with protein synthesis inhibitor rather than bactericidal activity. Solithromycin demonstrated the highest in vitro and intracellular potency against all Lp1 isolates compared to AZM. Given the rapid spread of resistance mechanisms among respiratory pathogens and the reported treatment failures in legionellosis, the development of this new fluoroketolide, already in phase 3 oral clinical studies, constitutes a promising alternative option for the treatment of legionellosis. PMID:24277019

  2. Lipase Activity among Bacteria Isolated from Amazonian Soils

    PubMed Central

    Willerding, André Luis; de Oliveira, Luiz Antonio; Moreira, Francisco Wesen; Germano, Mariana Gomes; Chagas, Aloísio Freitas

    2011-01-01

    The objective of this study was to select lipase-producing bacteria collected from different counties of the Amazon region. Of the 440 bacteria strains, 181 were selected for the lipase assay in qualitative tests at Petri dishes, being 75 (41%) lipase positive. The enzymatic index was determined during fifteen days at different temperatures (30°, 35°, 40°, and 45°C). The highest lipase activity was observed within 72 hours at 30°C. Twelve bacteria strains presented an index equal to or greater than the standard used like reference, demonstrating the potential of microbial resource. After the bioassay in Petri dishes, the selected bacteria strains were analyzed in quantitative tests on p-nitrophenyl palmitate (p-NPP). A group of the strains was selected for other phases of study with the use in oleaginous substrates of the Amazonian flora, aiming for the application in processes like oil biotransformation. PMID:22007294

  3. Investigating Biofilm Production, Coagulase and Hemolytic Activity in Candida Species Isolated From Denture Stomatitis Patients

    PubMed Central

    Yigit, Nimet; Aktas, Esin; Dagistan, Saadettin; Ayyildiz, Ahmet

    2011-01-01

    Objective: Oral candidiasis, in the form of Candida-associated denture stomatitis, represents a common disease in a large percentage of denture wearers, and Candida albicans remains the most commonly isolated species. In this study, we aimed to evaluate biofilm production, coagulase and hemolytic activity of Candida species isolated from denture stomatitis patients. Materials and Methods: This study included 70 patients (31 female, 39 male). Forty-eight of the patients were found to have a positive culture. A total of 48 Candida isolates representing five species, C. albicans (n=17), C. glabrata (n=10), C. krusei (n=9), C. kefyr (n=7) and C. parapsilosis (n=5), were tested. Their coagulase activities were evaluated by a classical tube coagulase test with rabbit plasma. A blood plate assay on 3% enriched sheep blood Sabouraud-dextrose agar (SDA) was used to determine their in vitro hemolytic activities. Biofilm production was determined by a visual tube method. Results: Twenty-one Candida isolates exhibited coagulase activity, and the coagulase activities of the C. albicans (64.7%) isolates were higher than other species. C. albicans, C. glabrata, C. kefyr and C. krusei species demonstrated beta hemolysis. C. parapsilosis strains failed to demonstrate any hemolytic activities. Fifteen (88.0%) of the C. albicans strains were biofilm positive. Six (35.2%) of these strains were strongly positive, 8 (47.0%) C. albicans strains were moderately positive and 1 (5.8%) C. albicans strain was weakly positive. Sixteen (51.6%) of the non-albicans Candida strains were biofilm positive while 15 (48.3%) did not produce biofilms. Conclusion: The results of this present study indicate coagulase, hemolytic activity and biofilm production by Candida spp. isolated from patients with denture stomatitis. Investigations of these virulence factors might be helpful in gaining information about the possible virulence of oral Candida species related to denture stomatitis. PMID:25610156

  4. In vitro activity of moxifloxacin against 923 anaerobes isolated from human intra-abdominal infections.

    PubMed

    Goldstein, Ellie J C; Citron, Diane M; Warren, Yumi A; Tyrrell, Kerin L; Merriam, C Vreni; Fernandez, Helen

    2006-01-01

    The in vitro activity of moxifloxacin against 923 recent anaerobic isolates obtained from pretreatment cultures in patients with complicated intra-abdominal infections was studied using the CLSI M11-A-6 agar dilution method. Moxifloxacin was active against 87% (96 of 110) Bacteroides fragilis strains at < or = 1 microg/ml and 87% (79 of 90) B. thetaiotaomicron strains at < or = 2 microg/ml. Species variation was seen, with B. uniformis, B. vulgatus, Clostridium clostridioforme, and C. symbiosum being least susceptible and accounting for most of the resistant isolates; excluding the aforementioned four resistant species, 86% (303 of 363) of Bacteroides species isolates and 94% (417 of 450) of all other genera and species were susceptible to < or = 2 microg/ml of moxifloxacin. Overall, moxifloxacin was active against 763 of 923 (83%) of strains at < or = 2 microg/ml, supporting its use as a monotherapy for some community-acquired intra-abdominal infections.

  5. Antibacterial Activity of Rhodomyrtus tomentosa (Aiton) Hassk. Leaf Extract against Clinical Isolates of Streptococcus pyogenes

    PubMed Central

    Limsuwan, Surasak; Kayser, Oliver; Voravuthikunchai, Supayang Piyawan

    2012-01-01

    Ethanol extract of Rhodomyrtus tomentosa (Aiton) Hassk. leaf was evaluated for antibacterial activity against 47 clinical isolates of Streptococcus pyogenes. The extract exhibited good anti-S. pyogenes activity against all the tested isolates with similar minimum inhibitory concentration (MIC, 3.91–62.5 μg mL−1) and minimum bactericidal concentration (MBC, 3.91–62.5 μg mL−1) ranges. No surviving cells were detected at 16 h after treatment with 8 × MIC of the extract. The extract-treated cells demonstrated no lysis and cytoplasmic leakage through the bacterial membrane. Electron micrographs further revealed that the extract did not cause any dramatic changes on the treated cells. Rhodomyrtone, an isolated compound, exhibited good anti-S. pyogenes activity (14 isolates), expressed very low MIC (0.39–1.56 μg mL−1) and MBC (0.39-1.56 μg mL−1) values. Rhodomyrtus tomentosa leaf extract and rhodomyrtone displayed promising antibacterial activity against clinical isolates of S. pyogenes. PMID:22973404

  6. Antibacterial Activity of Rhodomyrtus tomentosa (Aiton) Hassk. Leaf Extract against Clinical Isolates of Streptococcus pyogenes.

    PubMed

    Limsuwan, Surasak; Kayser, Oliver; Voravuthikunchai, Supayang Piyawan

    2012-01-01

    Ethanol extract of Rhodomyrtus tomentosa (Aiton) Hassk. leaf was evaluated for antibacterial activity against 47 clinical isolates of Streptococcus pyogenes. The extract exhibited good anti-S. pyogenes activity against all the tested isolates with similar minimum inhibitory concentration (MIC, 3.91-62.5 μg mL(-1)) and minimum bactericidal concentration (MBC, 3.91-62.5 μg mL(-1)) ranges. No surviving cells were detected at 16 h after treatment with 8 × MIC of the extract. The extract-treated cells demonstrated no lysis and cytoplasmic leakage through the bacterial membrane. Electron micrographs further revealed that the extract did not cause any dramatic changes on the treated cells. Rhodomyrtone, an isolated compound, exhibited good anti-S. pyogenes activity (14 isolates), expressed very low MIC (0.39-1.56 μg mL(-1)) and MBC (0.39-1.56 μg mL(-1)) values. Rhodomyrtus tomentosa leaf extract and rhodomyrtone displayed promising antibacterial activity against clinical isolates of S. pyogenes.

  7. Toxicogenomic analysis of pharmacological active coumarins isolated from Calophyllum brasiliense

    PubMed Central

    Gomez-Verjan, J.C.; Estrella-Parra, E.A.; Gonzalez-Sanchez, I.; Rivero-Segura, N.A.; Vazquez-Martinez, R.; Magos-Guerrero, G.; Mendoza-Villanueva, D.; Cerbón-Cervantes, M.A.; Reyes-Chilpa, R.

    2015-01-01

    Calophyllum brasiliense (Calophyllaceae) is a tropical rain forest tree, mainly distributed in South and Central America. It is an important source of bioactive natural products like, for instance soulatrolide, and mammea type coumarins. Soulatrolide is a tetracyclic dipyranocoumarins and a potent inhibitor of HIV-1 reverse transcriptase and Mycobacterium tuberculosis. Mammea A/BA and A/BB coumarins, pure or as a mixture, are highly active against several leukemia cell lines, Trypanosoma cruzi and Leishmania amazonensis. In the present work, a toxicogenomic analysis of Soulatrolide and Mammea A/BA + A/BB (3:1) mixture was performed in order to validate the toxicological potential of this type of compounds. Soulatrolide or mixture of mammea A/BA + A/BB (3:1) was administered orally to male mice (CD-1) at dose of 100 mg/kg/daily, for 1 week. After this time, mice were sacrificed, and RNA extracted from the liver of treated animals. Transcriptomic analysis was performed using Affymetrix Mouse Gene 1.0 ST Array. Robust microarray analysis (RMA) and two way ANOVA test revealed for mammea mixture treatment 46 genes upregulated and 72 downregulated genes; meanwhile, for soulatrolide 665 were upregulated and 1077 downregulated genes. Enrichment analysis for such genes revealed that in both type of treatments genetic expression were mainly involved in drug metabolism. Overall results indicate a safety profile. The microarray data complies with MIAME guidelines and are deposited in GEO under accession number GSE72755. PMID:26697389

  8. Toxicogenomic analysis of pharmacological active coumarins isolated from Calophyllum brasiliense.

    PubMed

    Gomez-Verjan, J C; Estrella-Parra, E A; Gonzalez-Sanchez, I; Rivero-Segura, N A; Vazquez-Martinez, R; Magos-Guerrero, G; Mendoza-Villanueva, D; Cerbón-Cervantes, M A; Reyes-Chilpa, R

    2015-12-01

    Calophyllum brasiliense (Calophyllaceae) is a tropical rain forest tree, mainly distributed in South and Central America. It is an important source of bioactive natural products like, for instance soulatrolide, and mammea type coumarins. Soulatrolide is a tetracyclic dipyranocoumarins and a potent inhibitor of HIV-1 reverse transcriptase and Mycobacterium tuberculosis. Mammea A/BA and A/BB coumarins, pure or as a mixture, are highly active against several leukemia cell lines, Trypanosoma cruzi and Leishmania amazonensis. In the present work, a toxicogenomic analysis of Soulatrolide and Mammea A/BA + A/BB (3:1) mixture was performed in order to validate the toxicological potential of this type of compounds. Soulatrolide or mixture of mammea A/BA + A/BB (3:1) was administered orally to male mice (CD-1) at dose of 100 mg/kg/daily, for 1 week. After this time, mice were sacrificed, and RNA extracted from the liver of treated animals. Transcriptomic analysis was performed using Affymetrix Mouse Gene 1.0 ST Array. Robust microarray analysis (RMA) and two way ANOVA test revealed for mammea mixture treatment 46 genes upregulated and 72 downregulated genes; meanwhile, for soulatrolide 665 were upregulated and 1077 downregulated genes. Enrichment analysis for such genes revealed that in both type of treatments genetic expression were mainly involved in drug metabolism. Overall results indicate a safety profile. The microarray data complies with MIAME guidelines and are deposited in GEO under accession number GSE72755.

  9. Brasilinolide A, a new macrolide antibiotic produced by Nocardia brasiliensis: producing strain, isolation and biological activity.

    PubMed

    Tanaka, Y; Komaki, H; Yazawa, K; Mikami, Y; Nemoto, A; Tojyo, T; Kadowaki, K; Shigemori, H; Kobayashi, J

    1997-12-01

    A new 32-membered macrolide antibiotic, brasilinolide A was isolated from the fermentation broth of Nocardia sp. IFM 0406. The producer was identified as Nocardia brasiliensis. The antibiotic was only active against Aspergillus niger, but not active against other fungi including yeasts as well as other filamentous like fungi and bacteria. Brasilinolide A exerted an immunosuppressive activity in the assay system of a mixed lymphocyte reaction (MLR).

  10. Fibrinolytic activity of kaempferol isolated from the fruits of Lagenaria siceraria (Molina) Standley.

    PubMed

    Rajput, M S; Mathur, Vineet; Agrawal, Purti; Chandrawanshi, H K; Pilaniya, Urmila

    2011-11-01

    This study was undertaken to isolate a flavonol, kaempferol, from the fruits of Lagenaria siceraria (bottle gourd) as a sole compound and to explore the fibrinolytic potential of the methanolic extract of the fruits of L. siceraria and the isolated compound using their in vitro activity. The fibrinolytic activity in terms of percentage of plasma clot liquefaction was determined by plasma clot lysis at 37°C in 24 h. The fibrinolytic activity of both substances was compared to the well-known thrombolytic agent streptokinase (30,000 IU). The percentage of fibrinolytic activity of the extract and isolated compound were found to be 54.72 ± 0.7210 and 77.37 ± 1.3010, respectively. Streptokinase was considered as the standard fibrinolytic enzyme for comparative purposes and had 91.46 ± 0.7625% fibrinolytic activity. The conclusion drawn in our study after testing the hypothesis by experimental procedures is that in vitro fibrinolytic activity on plasma clots is an inherent property of kaempferol isolated from the fruits of L. siceraria, and its comparison with streptokinase is a new aspect for further study.

  11. Isolation of dendritic cells from umbilical cord blood using magnetic activated cell sorting or adherence.

    PubMed

    Bie, Yachun; Xu, Qiuxiang; Zhang, Zhenyu

    2015-07-01

    Dendritic cells (DCs) are a highly specialized type of antigen-presenting cell. The present study describes and compares two methods for preparing DCs from umbilical cord blood. The first method involves the isolation of DCs by magnetic activated cell sorting (MACS). This technique isolates CD34(+) cells from cord blood and induces the formation of DCs by the addition of cytokines, granulocyte macrophage colony-stimulating factor and interleukin-4. The second method involves the generation of large numbers of DCs from cord blood using an adherent method, which isolates umbilical cord blood mononuclear cells and induces DCs in the same conditions as those used in MACS. The DCs were harvested following 7 days of incubation and observed with an inverted microscope. The phenotype of the cells was then analyzed by flow cytometry. The results revealed that, subsequent to 7 days of incubation, the differentiated DCs obtained using the adherent method were more mature than those isolated using MACS. However, these cells were unable to be maintained in culture for more than 9-10 days. By contrast, the DCs derived from CD34(+) cells by MACS were phenotypically stable and could be maintained for up to 3 weeks in culture. Either method produced DCs from cord blood. However, the DCs isolated using the MACS method demonstrated higher homogeneity, yield and viability than those obtained using the adherent method. Due to the various compositions of the monocyte subsets isolated, isolation methods affect the phenotypes and functions of the resultant DCs.

  12. Triterpenoids isolated from apple peels have potent antiproliferative activity and may be partially responsible for apple's anticancer activity.

    PubMed

    He, Xiangjiu; Liu, Rui Hai

    2007-05-30

    Bioactivity-guided fractionation of apple peels was used to determine the chemical identity of bioactive constituents. Thirteen triterpenoids were isolated, and their chemical structures were identified. Antiproliferative activities of the triterpenoids against human HepG2 liver cancer cells, MCF-7 breast cancer cells, and Caco-2 colon cancer cells were evaluated. Most of the triterpenoids showed high potential anticancer activities against the three human cancer cell lines. Among the compounds isolated, 2alpha-hydroxyursolic acid, 2alpha-hydroxy-3beta-{[(2E)-3-phenyl-1-oxo-2-propenyl]oxy}olean-12-en-28-oic acid, and 3beta-trans-p-coumaroyloxy-2alpha-hydroxyolean-12-en-28-oic acid showed higher antiproliferative activity toward HepG2 cancer cells. Ursolic acid, 2alpha-hydroxyursolic acid, and 3beta-trans-p-coumaroyloxy-2alpha-hydroxyolean-12-en-28-oic acid exhibited higher antiproliferative activity against MCF-7 cancer cells. All triterpenoids tested showed antiproliferative activity against Caco-2 cancer cells, especially 2alpha-hydroxyursolic acid, maslinic acid, 2alpha-hydroxy-3beta-{[(2E)-3-phenyl-1-oxo-2-propenyl]oxy}olean-12-en-28-oic acid, and 3beta-trans-p-coumaroyloxy-2alpha-hydroxyolean-12-en-28-oic acid, which displayed much higher antiproliferative activities. These results showed the triterpenoids isolated from apple peels have potent antiproliferative activity and may be partially responsible for the anticancer activities of whole apples.

  13. Endophytic Fungi Isolated from Oil-Seed Crop Jatropha curcas Produces Oil and Exhibit Antifungal Activity

    PubMed Central

    Kumar, Susheel; Kaushik, Nutan

    2013-01-01

    Jatropha curcas L., a perennial plant grown in tropics and subtropics is popularly known for its potential as biofuel. The plant is reported to survive under varying environmental conditions having tolerance to stress and an ability to manage pest and diseases. The plant was explored for its endophytic fungi for use in crop protection. Endophytic fungi were isolated from leaf of Jatropha curcas, collected from New Delhi, India. Four isolates were identified as Colletotrichum truncatum, and other isolates were identified as Nigrospora oryzae, Fusarium proliferatum, Guignardia cammillae, Alternaria destruens, and Chaetomium sp. Dual plate culture bioassays and bioactivity assays of solvent extracts of fungal mycelia showed that isolates of Colletotrichum truncatum were effective against plant pathogenic fungi Fusarium oxysporum and Sclerotinia sclerotiorum. Isolate EF13 had highest activity against S. sclerotiorum. Extracts of active endophytic fungi were prepared and tested against S. sclerotiorum. Ethyl acetate and methanol extract of C. truncatum EF10 showed 71.7% and 70% growth inhibition, respectively. Hexane extracts of C. truncatum isolates EF9, EF10, and EF13 yielded oil and the oil from EF10 was similar to oil of the host plant, i.e., J. curcas. PMID:23409154

  14. Endophytic fungi isolated from oil-seed crop Jatropha curcas produces oil and exhibit antifungal activity.

    PubMed

    Kumar, Susheel; Kaushik, Nutan

    2013-01-01

    Jatropha curcas L., a perennial plant grown in tropics and subtropics is popularly known for its potential as biofuel. The plant is reported to survive under varying environmental conditions having tolerance to stress and an ability to manage pest and diseases. The plant was explored for its endophytic fungi for use in crop protection. Endophytic fungi were isolated from leaf of Jatropha curcas, collected from New Delhi, India. Four isolates were identified as Colletotrichum truncatum, and other isolates were identified as Nigrospora oryzae, Fusarium proliferatum, Guignardia cammillae, Alternaria destruens, and Chaetomium sp. Dual plate culture bioassays and bioactivity assays of solvent extracts of fungal mycelia showed that isolates of Colletotrichum truncatum were effective against plant pathogenic fungi Fusarium oxysporum and Sclerotinia sclerotiorum. Isolate EF13 had highest activity against S. sclerotiorum. Extracts of active endophytic fungi were prepared and tested against S. sclerotiorum. Ethyl acetate and methanol extract of C. truncatum EF10 showed 71.7% and 70% growth inhibition, respectively. Hexane extracts of C. truncatum isolates EF9, EF10, and EF13 yielded oil and the oil from EF10 was similar to oil of the host plant, i.e., J. curcas.

  15. Negative correlation between phospholipase and esterase activity produced by Fusarium isolates

    PubMed Central

    Ishida, K.; Alviano, D.S.; Silva, B.G.; Guerra, C.R.; Costa, A.S.; Nucci, M.; Alviano, C.S.; Rozental, S.

    2012-01-01

    Fusarium species have emerged as one of the more outstanding groups of clinically important filamentous fungi, causing localized and life-threatening invasive infections with high morbidity and mortality. The ability to produce different types of hydrolytic enzymes is thought to be an important virulence mechanism of fungal pathogens and could be associated with the environment of the microorganism. Here, we have measured the production of two distinct lipolytic enzymes, phospholipase and esterase, by sixteen Fusarium isolates recovered from the hospital environment, immunocompromised patients' blood cultures, foot interdigital space scrapings from immunocompromised patients, and foot interdigital space scrapings from immunocompetent patients (4 isolates each). Fourteen of these 16 isolates were identified as Fusarium solani species complex (FSSC) and two were identified as F. oxysporum species complex (FOSC). Some relevant genus characteristics were visualized by light and electron microscopy such as curved and multicelled macroconidia with 3 or 4 septa, microconidia, phialides, and abundant chlamydospores. All Fusarium isolates were able to produce esterase and phospholipase under the experimental conditions. However, a negative correlation was observed between these two enzymes, indicating that a Fusarium isolate with high phospholipase activity has low esterase activity and vice versa. In addition, Fusarium isolated from clinical material produced more phospholipases, while environmental strains produced more esterases. These observations may be correlated with the different types of substrates that these fungi need to degrade during their nutrition processes. PMID:22415116

  16. Isolation and analysis of mannose/trehalose/maltose specific lectin from jack bean with antibruchid activity.

    PubMed

    Shanmugavel, Sakthivelkumar; Velayutham, Veeramani; Kamalanathan, Tamilarasan; Periasamy, Mullainadhan; Munusamy, Arumugam; Sundaram, Janarthanan

    2016-10-01

    A lectin with insecticidal property against the stored product pest, Callosobruchus maculatus was successfully isolated from the seeds of Canavalia virosa using standard affinity chromatography. The isolated molecule typically behaved like a lectin in its characteristics. It agglutinated indicator red blood cells (RBC) in its native as well as enzyme treated conditions. The enzyme treated RBC types exhibited a very high hemagglutination (HA) titre values and this property of isolated molecule behaved like arcelin, the lectin-like molecules reported from several species of Phaseolus. As a characteristic feature of a lectin, the isolated molecule effectively inhibited the agglutination of indicator RBC types with simple and complex carbohydrates including glycoproteins. This nature of the isolated molecule also relate with characteristic feature of arcelin isoforms in inhibiting HA activity with complex glycoproteins as reported in many studies. Most interestingly, the present study disclosed trehalose as a potent inhibitor of C. virosa lectin. Therefore, feeding insect pests on the lectin like arcelin could serve as antibiosis factor/anti-insect activity. The molecular characteristics of this isolated molecule and its mass studies too revealed its homology with arcelin, arcelin-1, 2 and 6 isoforms of P. vulgaris and lectin from Canavalia cathartica, C. lineata and C. brasiliensis.

  17. Genetic diversity and antifungal activity of native Pseudomonas isolated from maize plants grown in a central region of Argentina.

    PubMed

    Cordero, Paula; Cavigliasso, Andrea; Príncipe, Analía; Godino, Agustina; Jofré, Edgardo; Mori, Gladys; Fischer, Sonia

    2012-07-01

    Pseudomonas strains producing antimicrobial secondary metabolites play an important role in the biocontrol of phytopathogenic fungi. In this study, native Pseudomonas spp. isolates were obtained from the rhizosphere, endorhizosphere and bulk soil of maize fields in Córdoba (Argentina) during both the vegetative and reproductive stages of plant growth. However, the diversity based on repetitive-element PCR (rep-PCR) and amplified ribosomal DNA restriction analysis (ARDRA) fingerprinting was not associated with the stage of plant growth. Moreover, the antagonistic activity of the native isolates against phytopathogenic fungi was evaluated in vitro. Several strains inhibited members of the genera Fusarium, Sclerotinia or Sclerotium and this antagonism was related to their ability to produce secondary metabolites. A phylogenetic analysis based on rpoB or 16S rRNA gene sequences confirmed that the isolates DGR22, MGR4 and MGR39 with high biocontrol potential belonged to the genus Pseudomonas. Some native strains of Pseudomonas were also able to synthesise indole acetic acid and to solubilise phosphate, thus possessing potential plant growth-promoting (PGPR) traits, in addition to their antifungal activity. It was possible to establish a relationship between PGPR or biocontrol activity and the phylogeny of the strains. The study allowed the creation of a local collection of indigenous Pseudomonas which could be applied in agriculture to minimise the utilisation of chemical pesticides and fertilisers.

  18. Isolation of major components from the roots of Godmania aesculifolia and determination of their antifungal activities.

    PubMed

    Tamayo-Castillo, Giselle; Vásquez, Víctor; Ríos, María Isabel; Rodríguez, María Victoria; Solano, Godofredo; Zacchino, Susana; Gupta, Mahabir P

    2013-12-01

    From the methanol root extract of Godmania aesculifolia, a species selected in a multinational OAS program aimed at discovering antifungal compounds from Latin American plants, a new chavicol diglycoside (1), the known 3,4-dihydroxy-2-(3-methylbut-2-en-1-yl)-3,4-dihydronaphthalen-1(2H)-one (2), and lapachol (3) were isolated and characterized by 1D and 2D NMR and MS techniques. Only 3 exhibited fairly good activity against a panel of clinical isolates of Cryptococcus neoformans (MIC50 between 7.8 and 31.2 µg/mL) and moderate activities against Candida spp. and non-albicans Candida spp.

  19. First isolated active titanium peroxo complex: characterization and theoretical study.

    PubMed

    Kholdeeva, Oxana A; Trubitsina, Tatiana A; Maksimovskaya, Raisa I; Golovin, Anatolii V; Neiwert, Wade A; Kolesov, Boris A; López, Xavier; Poblet, Josep M

    2004-04-05

    The protonated titanium peroxo complex [Bu(4)N](4)[HPTi(O(2))W(11)O(39)] (1) has been first prepared via interaction of the micro-oxo dimeric heteropolytungstate [Bu(4)N](8)[(PTiW(11)O(39))(2)O] (3) with an excess of 30% aqueous H(2)O(2) in MeCN. Peroxo complex 1 has been characterized by using elemental analysis, UV-vis, IR, resonance Raman (RR), (31)P and (183)W NMR spectroscopy, cyclic voltammetry, and potentiometric titration. The electronic and vibrational spectra of 1 are very similar to those of the well-known unprotonated titanium peroxo complex [Bu(4)N](5)[PTi(O(2))W(11)O(39)] (2), while (31)P and (183)W NMR spectra differ significantly. A compilation of the physicochemical techniques supports a monomeric Keggin type structure of 1 bearing one peroxo ligand attached to Ti(IV) in a eta(2)-coordination mode. The protonation of the titanium peroxo complex results in an increase of the redox potential of the peroxo group, E(1/2) = 1.25 and 0.88 V relative to Ag/AgCl reference electrode for 1 and 2, respectively. In contrast to 2, 1 readily reacts with 2,3,6-trimethylphenol (TMP) at 40 degrees C in MeCN to give 2,2',3,3',5,5'-hexamethyl-4,4'-biphenol (BP) and 2,3,5-trimethyl-p-benzoquinone (TMBQ). The proportion between BP and TMBQ in the reaction products depends on the TMP/1 ratio. When a 2-fold excess of TMP is used, the main reaction product is BP (90%), while using a 2-fold excess of 1 leads to TMBQ (95%). On the basis of the product study, a homolytic oxidation mechanism that implicates the formation of phenoxyl radicals is suggested. The RR deuterium labeling experiments show that the activating proton is most likely localized at a Ti-O-W bridging oxygen rather than at the peroxo group. Theoretical calculations carried out at the DFT level on the protonated and unprotonated titanium peroxo derivatives also propose that the most stable complex is formed preferentially after protonation of the Ti-O-W site; however, both Ti-OH-W and TiOO-H protonated anions

  20. Isolation of Lactic Acid Bacteria Showing Antioxidative and Probiotic Activities from Kimchi and Infant Feces.

    PubMed

    Ji, Keunho; Jang, Na Young; Kim, Young Tae

    2015-09-01

    The purpose of this study was to investigate lactic acid bacteria with antioxidative and probiotic activities isolated from Korean healthy infant feces and kimchi. Isolates A1, A2, S1, S2, and S3 were assigned to Lactobacillus sp. and isolates A3, A4, E1, E2, E3, and E4 were assigned to Leuconostoc sp. on the basis of their physiological properties and 16S ribosomal DNA sequence analysis. Most strains were confirmed as safe bioresources through nonhemolytic activities and non-production of harmful enzymes such as β-glucosidase, β- glucuronidase and tryptophanase. The 11 isolates showed different resistance to acid and bile acids. In addition, they exhibited antibacterial activity against foodborne bacteria, especially Bacillus cereus, Listeria monocytogenes, and Escherichia coli. Furthermore, all strains showed significantly high levels of hydrophobicity. The antioxidant effects of culture filtrates of the 11 strains included 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging capacity, 2.2'- azino-bis (2-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical cation scavenging activity, and superoxide dismutase activity. The results revealed that most of the culture filtrates have effective scavenging activity for DPPH and ABTS radicals. All strains appeared to have effective superoxide dismutase activity. In conclusion, the isolated strains A1, A3, S1, and S3 have significant probiotic activities applicable to the development of functional foods and health-related products. These strains might also contribute to preventing and controlling several diseases associated with oxidative stress, when used as probiotics.

  1. Isolation of rhizospheric and roots endophytic actinomycetes from Leguminosae plant and their activities to inhibit soybean pathogen, Xanthomonas campestris pv. glycine.

    PubMed

    Mingma, Ratchanee; Pathom-aree, Wasu; Trakulnaleamsai, Savitr; Thamchaipenet, Arinthip; Duangmal, Kannika

    2014-01-01

    In this study, actinomycetes from roots and rhizospheric soils of leguminous plants were isolated using starch casein agar supplemented with antifungal and antibacterial antibiotics. Three hundred and seventeen actinomycetes were isolated with 77 isolates obtained from plant roots and 240 isolates from rhizospheric soils. Analysis of whole-organism hydrolysates showed that 289 strains were rich in the LL-isomer of diaminopimelic acid, a result consistent with their assignment to the streptomycetes. The remaining 28 strains were assigned to non-streptomycetes based on the presence of meso-isomer of diaminopimelic acid in cell wall. Sixty-four isolates (20.2%) showed antagonistic activity against soybean pathogen Xanthomonas campestris pv. glycine by agar overlay method. Isolate RM 365 showed the highest activity with an inhibition ratio of 3.79, with no inhibitory activity on the growth of Rhizobium japonicum TISTR 079, Rhizobium sp. TISTR 061 and Rhizobium sp. TISTR 063. The 16S rRNA gene sequence analysis revealed that isolate RM 365 shared 99.28% similarity to Streptomyces caeruleatus GIMN4(T) (GQ329712). In addition, isolates which contained meso-DAP were also identified by 16S rRNA gene sequence analysis. The results showed that they were members of the genus Amycolatopsis, Isoptericola, Micromonospora, Microbispora, Nocardia, Nonomuraea, Promicromonospora and Pseudonocardia.

  2. Isolation, identification, and antibacterial activity of chemical compounds from ethanolic extract of suji leaf (Pleomele angusifolia NE Brown)

    NASA Astrophysics Data System (ADS)

    Faridah; Natalia; Lina, Maria; W, Hendig

    2014-03-01

    Suji (Pleomele angustifolia NE Brown) is one of the medicinal plants of the tribe of Liliaceae, empirically useful to treat coughs and respiratory diseases such as tuberculosis (TB) and pneumonia. In this study, ethanolic extract of suji leaves was tested its activity against bacteria that attacks the respiratory organs, namely Mycobacterium tuberculosis and Streptococcus pneumoniae, using a paper disc diffusion and dilution agar method. These extracts have activity in inhibiting the growth of M. tuberculosis at a concentration of 8 mg and against S. pneumoniae at a concentration of 4 mg. The fractions were tested their antibacterial activity against Streptococcus pneumoniae using paper disc diffusion method. The most active fraction was chosen based on the inhibition diameter. The fractions contained flavonoids, steroids, and essential oils. The precipitate isolated from the extraction process shows needle-shaped, white, cold and tasteless crystals. Moreover, the HPLC analysis of isolate revealed a single peak with a retention time of 7.183 minutes. The exact compounds in the isolate could not be determined but it was known the compounds contained the functional groups of alkene, alkane, C=O, -OH. Test results obtained from UV-Vis spectrophotometer provides maximum absorption at a wavelength of 203.0 nm.

  3. Isolation and characterization of a bacterium that degrades various polyester-based biodegradable plastics.

    PubMed

    Teeraphatpornchai, T; Nakajima-Kambe, T; Shigeno-Akutsu, Y; Nakayama, M; Nomura, N; Nakahara, T; Uchiyama, H

    2003-01-01

    Microorganisms isolated from soil samples were screened for their ability to degrade various biodegradable polyester-based plastics. The most active strain, designated as strain TB-13, was selected as the best strain for degrading these plastics. From its phenotypic and genetic characteristics, strain TB-13 was closely related to Paenibacillus amyloyticus. It could degrade poly(lactic acid), poly(butylene succinate), poly(butylene succinate-co-adipate), poly(caprolactone) and poly(ethylene succinate) but not poly(hydroxybutylate-co-valerate). However, it could not utilize these plastics as sole carbon sources. Both protease and esterase activities, which may be involved in the degradation of plastic, were constitutively detected in the culture broth.

  4. Isolation and characterization of actinomycetes strains that produce phospholipase D having high transphosphatidylation activity.

    PubMed

    Nakazawa, Yozo; Uchino, Masataka; Sagane, Yoshimasa; Sato, Hiroaki; Takano, Katsumi

    2009-01-01

    The present study was conducted to screen microorganisms that produce phospholipase D (PLD), and we especially focused on the strains having high transphosphatidylation activity. Eighty bacterial strains were isolated from soil samples by a screening method utilizing a preliminary selection medium with phosphatidylcholine (PC) as the sole carbon source. The culture supernatants were then assayed for PLD activity. The finding of dual PLD activities in cultures revealed that the hydrolytic and transphosphatidylation activities were correlated. Consequently, six strains were selected as stably producing PLD enzyme(s) during continuous subcultures. The culture supernatants of selected strains synthesized phosphatidylglycerol, phosphatidylserine and phosphatidylethanolamine from PC with high conversion rates. These isolated strains will be made available to carry out phospholipid modification through the efficient transphosphatidylation activity of the PLD that they produce.

  5. Spasmolytic activity of a herbal drug isolated from Tephrosia purpurea in guinea pigs.

    PubMed

    Soni, Kapil K; Khare, M L; Saxena, R C

    2004-04-01

    We investigated the spasmolytic activity of herbal drugs isolated from Tephrosia purpurea on guinea pigs for the treatment of asthma in India. For this investigation, the herbal drug was extracted with 70% ethanol in soxhlet apparatus. After purification and isolution, the drug was used in experimental animals to observe prophylactic activity. For anaphylactic activity, horse serum 0.5 ml along with triple antigen (0.5 ml) was induced in guinea pigs. To observe prophylactic activity, male guinea pigs weighing about 250-450 gms were killed by cervical dislocation and the trachea was isolated. Each trachea was cut in to six segments. Each segment consists of three cartilage rings. Each end of tracheal muscles was attached to the bronchospasm transducers for isometric recording of the tension charges on a polygraph. The results of experiments clearly showed the spasmolytic activity of the drug. The preliminary phytochemical investigation, however shows the presence of glycoside saponins.

  6. Isolating plasma from blood using a dielectrophoresis-active hydrophoretic device.

    PubMed

    Yan, Sheng; Zhang, Jun; Alici, Gursel; Du, Haiping; Zhu, Yonggang; Li, Weihua

    2014-08-21

    Plasma is a complex substance that contains proteins and circulating nucleic acids and viruses that can be utilised for clinical diagnostics, albeit a precise analysis depends on the plasma being totally free of cells. We proposed the use of a dielectrophoresis (DEP)-active hydrophoretic method to isolate plasma from blood in a high-throughput manner. This microfluidic device consists of anisotropic microstructures embedded on the top of the channel which generate lateral pressure gradients while interdigitised electrodes lay on the bottom of the channel which can push particles or cells into a higher level using a negative DEP force. Large and small particles or cells (3 μm and 10 μm particles, and red blood cells, white blood cells, and platelets) can be focused at the same time in our DEP-active hydrophoretic device at an appropriate flow rate and applied voltage. Based on this principle, all the blood cells were filtrated from whole blood and then the plasma was extracted with a purity of 94.2% and a yield of 16.5% at a flow rate of 10 μL min(-1). This solved the challenging problem caused by the relatively low throughput of the DEP based device. Our DEP-active hydrophoretic device is a flexible and tunable system that can control the lateral positions of particles by modulating the external voltages without redesigning and fabricating a new channel, and because it is easy to operate, it is easily compatible with other microfluidic platforms that are used for further detection.

  7. Millimetre-wave isolator based on Al substituted Ba ferrite

    NASA Astrophysics Data System (ADS)

    Ustinov, A. B.; Vinnik, D. A.; Belyavskii, P. Yu; Gudkova, S. A.; Zakharchuk, I.; Lähderanta, E.

    2016-11-01

    A mm-wave isolator is fabricated and studied. The operating frequency of the devices is 78.5 GHz. A bandwidth at the level of -3 dB equals 1.6 GHz. The device used a flux grown single-crystal aluminum substituted barium ferrite.

  8. Antagonistic Activity of Nocardia brasiliensis PTCC 1422 Against Isolated Enterobacteriaceae from Urinary Tract Infections.

    PubMed

    Jalali, Hossnieh Kafshdar; Salamatzadeh, Abdolreza; Jalali, Arezou Kafshdar; Kashani, Hamed Haddad; Asbchin, Salman Ahmadi; Issazadeh, Khosro

    2016-03-01

    The main drawback of current antibiotic therapies is the emergence and rapid increase in antibiotic resistance. Nocardiae are aerobic, Gram-positive, catalase-positive, non-motile actinomycetes. Nocardia brasiliensis was reported as antibiotic producer. The purpose of the study was to determine antibacterial activity of N. brasiliensis PTCC 1422 against isolated Enterobacteriaceae from urinary tract infections (UTIs). The common bacteria from UTIs were isolated from hospital samples. Antimicrobial susceptibility test was performed for the isolated pathogens using Kirby-Bauer disk diffusion method according to clinical and Laboratory Standards Institute guideline. Antagonistic activity of N. brasiliensis PTCC 1422 was examined with well diffusion methods. Supernatant of N. brasiliensis PTCC 1422 by submerged culture was analyzed with gas chromatography-mass spectrometry. Isolated strains included Escherichia coli, Klebsiella pneumoniae, Serratia marcescens and Proteus mirabilis. The most common pathogen isolated was E. coli (72.5%). Bacterial isolates revealed the presence of high levels of antimicrobial resistances to ceftriaxone and low levels of resistance to cephalexin. Supernatant of N. brasiliensis PTCC 1422 showed antibacterial activity against all of the isolated microorganisms in well diffusion method. The antibiotic resistance among the uropathogens is an evolving process, so a routine surveillance to monitor the etiologic agents of UTI and the resistance pattern should be carried out timely to choose the most effective empirical treatment by the physicians. Our present investigation indicates that the substances present in the N. brasiliensis PTCC 1422 could be used to inhibit the growth of human pathogen. Antibacterial resistance among bacterial uropathogen is an evolving process. Therefore, in the field on the need of re-evaluation of empirical treatment of UTIs, our present. The study has demonstrated that N. brasiliensis PTCC 1422 has a high potential

  9. Deinococcus aquaticus sp. nov., isolated from fresh water, and Deinococcus caeni sp. nov., isolated from activated sludge.

    PubMed

    Im, Wan-Taek; Jung, Hae-Min; Ten, Leonid N; Kim, Myung Kyum; Bora, Nagamani; Goodfellow, Michael; Lim, Sangyong; Jung, Jinwoo; Lee, Sung-Taik

    2008-10-01

    The taxonomic positions of two environmental isolates from South Korea were established using a combination of genotypic and phenotypic data. The organisms, designated PB314(T) and Ho-08(T), were Gram-negative, rod-shaped and non-spore-forming and had chemotaxonomic properties consistent with their classification in the genus Deinococcus 16S rRNA gene tree, the highest sequence similarities being shown to the type strains of Deinococcus grandis (96.3-96.7 %) and Deinococcus indicus (96.3-96.4 %). The isolates shared relatively high 16S rRNA gene sequence similarity (98.1 %) but had a DNA-DNA relatedness value of only 22 %. Chemotaxonomic data revealed that both strains possess quinone system MK-8 as the predominant compound, C(16 : 1)omega7c and C(16 : 0) as major fatty acids and ornithine as a diamino acid in the peptidoglycan structure, corroborating our assignment of the strains to the genus Deinococcus. The results of phylogenetic analyses based on 16S rRNA gene sequences, DNA-DNA relatedness values and physiological and biochemical tests clearly demonstrated that the two strains represent distinct species. On the basis of these data, two novel species, Deinococcus aquaticus sp. nov. (type strain PB314(T) =KCTC 12552(T) =NBRC 101311(T)) and Deinococcus caeni sp. nov. (type strain Ho-08(T) =KCTC 12553(T) =NBRC 101312(T)), are proposed.

  10. Active fault detection and isolation of discrete-time linear time-varying systems: a set-membership approach

    NASA Astrophysics Data System (ADS)

    Mojtaba Tabatabaeipour, Seyed

    2015-08-01

    Active fault detection and isolation (AFDI) is used for detection and isolation of faults that are hidden in the normal operation because of a low excitation signal or due to the regulatory actions of the controller. In this paper, a new AFDI method based on set-membership approaches is proposed. In set-membership approaches, instead of a point-wise estimation of the states, a set-valued estimation of them is computed. If this set becomes empty the given model of the system is not consistent with the measurements. Therefore, the model is falsified. When more than one model of the system remains un-falsified, the AFDI method is used to generate an auxiliary signal that is injected into the system for detection and isolation of faults that remain otherwise hidden or non-isolated using passive FDI (PFDI) methods. Having the set-valued estimation of the states for each model, the proposed AFDI method finds an optimal input signal that guarantees FDI in a finite time horizon. The input signal is updated at each iteration in a decreasing receding horizon manner based on the set-valued estimation of the current states and un-falsified models at the current sample time. The problem is solved by a number of linear and quadratic programming problems, which result in a computationally efficient algorithm. The method is tested on a numerical example as well as on the pitch actuator of a benchmark wind turbine.

  11. Epidemiological investigation of Pseudomonas aeruginosa nosocomial bacteraemia isolates by PCR-based DNA fingerprinting analysis.

    PubMed

    Liu, Y; Davin-Regli, A; Bosi, C; Charrel, R N; Bollet, C

    1996-11-01

    Between July 1994 and March 1995, 64 isolates of Pseudomonas aeruginosa were implicated in bacteraemia in 25 cancer patients in five wards of two hospitals. These, together with 24 environmental isolates and one isolate from a bacteraemia in a non-cancer patient were examined by three PCR-based DNA fingerprinting methods: random amplified polymorphic DNA (RAPD), enterobacterial-repetitive intergenic consensus (ERIC)-PCR, and 16S-23S spacer region-based RAPD. These methods were reproducible, discriminatory and showed close agreement; all indicated that 47 isolates that had caused bacteraemia in 19 cancer patients were indistinguishable. Seventeen other isolates that had caused bacteraemia in 10 cancer patients were discriminated into eight further groups, and the 24 environmental and non-cancer patient isolates into further distinct groups. No environmental source of the epidemic strain was found, but it was suspected that the outbreak was related to infusion implants.

  12. Isolation, chemical characterization, and immunomodulatory activity of naturally acetylated hemicelluloses from bamboo shavings* #

    PubMed Central

    Huang, Ju-qing; Qi, Rui-ting; Pang, Mei-rong; Liu, Cong; Li, Guang-yu; Zhang, Ying

    2017-01-01

    Bamboo shavings, the outer or intermediate layer of bamboo stems, are the bulk of by-products produced in bamboo processing. In this study we investigated the isolation, chemical characterization, and immunostimulatory activity in vitro of the hemicelluloses from bamboo shavings. Shavings were first pretreated by steam explosion. The optimal pretreatment was found to be steam explosion at 2.2 MPa for 1 min. Following this pretreatment, the yield of hemicelluloses reached (2.05±0.22)% (based on the dry dewaxed raw materials), which was 5.7-fold higher than that of untreated samples. Bamboo-shavings hemicellulose (BSH) was then prepared by hot water extraction and ethanol precipitation from the steam-exploded shavings. Purification of BSH by anion-exchange chromatography of diethylaminoethanol (DEAE)-sepharose Fast Flow resulted in a neutral fraction (BSH-1, purity of 95.3%, yield of 1.06%) and an acidic fraction (BSH-2, purity of 92.5%, yield of 0.79%). The weight-average molecular weights (M w) of BSH-1 and BSH-2 were 12 800 and 11 300 g/mol, respectively. Chemical and structural analyses by Fourier transform infrared spectroscopy (FT-IR), 1D (1H and 13C) and 2D (heteronuclear single quantum correlation (HSQC)) nuclear magnetic resonance (NMR) spectra revealed that BSH-1 was O-acetylated-arabinoxylan and BSH-2 was O-acetylated-(4-O-methylglucurono)-arabinoxylan. BSH-1 had a higher content of acetyl groups than BSH-2. For the immunomodulatory activity in vitro, BSH and BSH-2 significantly stimulated mouse splenocyte proliferation while BSH-1 had no effect; BSH, BSH-1, and BSH-2 markedly enhanced the phagocytosis activity and nitric oxide production of the murine macrophage RAW264.7 in a dose-dependent manner. Our results suggest that the water-extractable hemicelluloses from steam-exploded bamboo shavings are naturally acetylated and have immunostimulatory activity. PMID:28124842

  13. Isolation, chemical characterization, and immunomodulatory activity of naturally acetylated hemicelluloses from bamboo shavings.

    PubMed

    Huang, Ju-Qing; Qi, Rui-Ting; Pang, Mei-Rong; Liu, Cong; Li, Guang-Yu; Zhang, Ying

    Bamboo shavings, the outer or intermediate layer of bamboo stems, are the bulk of by-products produced in bamboo processing. In this study we investigated the isolation, chemical characterization, and immunostimulatory activity in vitro of the hemicelluloses from bamboo shavings. Shavings were first pretreated by steam explosion. The optimal pretreatment was found to be steam explosion at 2.2 MPa for 1 min. Following this pretreatment, the yield of hemicelluloses reached (2.05±0.22)% (based on the dry dewaxed raw materials), which was 5.7-fold higher than that of untreated samples. Bamboo-shavings hemicellulose (BSH) was then prepared by hot water extraction and ethanol precipitation from the steam-exploded shavings. Purification of BSH by anion-exchange chromatography of diethylaminoethanol (DEAE)-sepharose Fast Flow resulted in a neutral fraction (BSH-1, purity of 95.3%, yield of 1.06%) and an acidic fraction (BSH-2, purity of 92.5%, yield of 0.79%). The weight-average molecular weights (Mw) of BSH-1 and BSH-2 were 12 800 and 11 300 g/mol, respectively. Chemical and structural analyses by Fourier transform infrared spectroscopy (FT-IR), 1D ((1)H and (13)C) and 2D (heteronuclear single quantum correlation (HSQC)) nuclear magnetic resonance (NMR) spectra revealed that BSH-1 was O-acetylated-arabinoxylan and BSH-2 was O-acetylated-(4-O-methylglucurono)-arabinoxylan. BSH-1 had a higher content of acetyl groups than BSH-2. For the immunomodulatory activity in vitro, BSH and BSH-2 significantly stimulated mouse splenocyte proliferation while BSH-1 had no effect; BSH, BSH-1, and BSH-2 markedly enhanced the phagocytosis activity and nitric oxide production of the murine macrophage RAW264.7 in a dose-dependent manner. Our results suggest that the water-extractable hemicelluloses from steam-exploded bamboo shavings are naturally acetylated and have immunostimulatory activity.

  14. Substrate Ablation of Ventricular Tachycardia: Late Potentials, Scar Dechanneling, Local Abnormal Ventricular Activities, Core Isolation, and Homogenization.

    PubMed

    Briceño, David F; Romero, Jorge; Gianni, Carola; Mohanty, Sanghamitra; Villablanca, Pedro A; Natale, Andrea; Di Biase, Luigi

    2017-03-01

    Ventricular arrhythmias are a frequent cause of mortality in patients with ischemic cardiomyopathy and nonischemic cardiomyopathy. Scar-related reentry represents the most common arrhythmia substrate in patients with recurrent episodes of sustained ventricular tachycardia (VT). Initial mapping of scar-related VT circuits is focused on identifying arrhythmogenic tissue. The substrate-based strategies include targeting late potentials, scar dechanneling, local abnormal ventricular activities, core isolation, and homogenization of the scar. Even though substrate-based strategies for VT ablation have shown promising outcomes for patients with structural heart disease related to ischemic cardiomyopathy, the data are scarce for patients with nonischemic substrates.

  15. Spice oil cinnamaldehyde exhibits potent anticandidal activity against fluconazole resistant clinical isolates.

    PubMed

    Shreaz, Sheikh; Bhatia, Rimple; Khan, Neelofar; Muralidhar, Sumathi; Basir, Seemi F; Manzoor, Nikhat; Khan, Luqman Ahmad

    2011-10-01

    Fluconazole resistance is becoming an important clinical concern. We studied the in vitro effects of cinnamaldehyde against 18 fluconazole-resistant Candida isolates. MIC(90) of cinnamaldehyde against different Candida isolates ranged 100-500 μg/ml. Growth and sensitivity of the organisms were significantly affected by cinnamaldehyde at different concentrations. The rapid irreversible action of this compound on fungal cells suggested membrane-located targets for its action. Insight studies to mechanism suggested that cinnamaldehyde exerts its antifungal activity by targeting sterol biosynthesis and plasma membrane ATPase activity. Inhibition of H(+) (-)ATPase leads to intracellular acidification and cell death. Toxicity against H9c2 rat cardiac myoblasts was studied to exclude the possibility of further associated cytotoxicity. The observed selectively fungicidal characteristics against fluconazole-resistant Candida isolates signify a promising candidature of this essential oil as an antifungal agent in treatments for candidosis.

  16. Luteolibacter yonseiensis sp. nov., isolated from activated sludge using algal metabolites.

    PubMed

    Park, Joonhong; Baek, Gyu Seok; Woo, Sung-Geun; Lee, Jangho; Yang, Jihoon; Lee, Juyoun

    2013-05-01

    A Gram-negative, rod-shaped, aerobic bacterial strain, designated EBTL01(T), was isolated from activated sludge by using metabolites of microalgae Ankistrodesmus gracilis SAG278-2. Phylogenetic analyses based on 16S rRNA gene sequence showed that strain EBTL01(T) belongs to the family Verrucomicrobiaceae, class Verrucomicrobiae, and is related most closely to Luteolibacter pohnpeiensis A4T-83(T) (95.5 % sequence similarity) and Luteolibacter algae A5J-41-2(T) (95.2 %). The G+C content of the genomic DNA of strain EBTL01(T) was 56.3 mol% and the menaquinone MK-9 was detected as the predominant quinone. Major fatty acid components were iso-C14 : 0, C16 : 1ω7c and C16 : 0. The amino acids of the cell-wall peptidoglycan contained muramic acid and meso-diaminopimelic acid. These profile results supported the affiliation of strain EBTL01(T) to the genus Luteolibacter. On the other hand, based on chemotaxonomic properties and phenotypic characteristics, strain EBTL01(T) could be clearly differentiated from its phylogenetic neighbours. Therefore, strain EBTL01(T) represents a novel species of the genus Luteolibacter, for which the name Luteolibacter yonseiensis sp. nov. is proposed. The type strain is EBTL01(T) ( = KCTC 23678(T) = JCM 18052(T)).

  17. Prosthecobacter algae sp. nov., isolated from activated sludge using algal metabolites.

    PubMed

    Lee, Jangho; Park, Banghyo; Woo, Sung-Geun; Lee, Juyoun; Park, Joonhong

    2014-02-01

    A Gram-stain-negative, fusiform-shaped, facultatively anaerobic bacterial strain, designated EBTL04(T), was isolated from activated sludge using algal metabolites and taxonomically characterized through polyphasic investigation. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain EBTL04(T) belongs to the family Verrucomicrobiaceae, class Verrucomicrobiae, and is closely related to Prosthecobacter dejongeii DSM 12251(T) (98.6 % sequence similarity), Prosthecobacter fusiformis ATCC 25309(T) (97.9 %), Prosthecobacter debontii DSM 14044(T) (97.5%), Prosthecobacter vanneervenii DSM 12252(T) (94.7%) and Prosthecobacter fluviatilis KCTC 22182(T) (93.7%). The G+C content of the genomic DNA of strain EBTL04(T) was 62.7 mol%. The menaquinone MK-6 was detected as the predominant quinone. Strain EBTL04(T) contained phosphatidylethanolamine, phosphatidylglycerol and phosphatidylserine as major polar lipids. A fatty acid profile with C(16 : 1)ω5c, iso-C(14 : 0), C(16 : 0), anteiso-C(15 : 0) and C(14 : 0) as the major components supported the classification of strain EBTL04(T) in the genus Prosthecobacter. Based on several phenotypic, genotypic and chemotaxonomic features, strain EBTL04(T) was clearly differentiated from its phylogenetic neighbours. Therefore, strain EBTL04(T) should be considered to represent a novel species of the genus Prosthecobacter, for which the name Prosthecobacter algae sp. nov. is proposed. The type strain is EBTL04(T) ( = KCTC 23681(T) = JCM 18053(T)).

  18. In vitro antimicrobial activity against 10 North American and European Lawsonia intracellularis isolates.

    PubMed

    Wattanaphansak, Suphot; Singer, Randall S; Gebhart, Connie J

    2009-03-02

    The objective of this study was to determine the in vitro minimum inhibitory concentration (MIC) of antimicrobials against 10 isolates of Lawsonia intracellularis, the etiological agent of proliferative enteropathy (PE). Antimicrobials tested included carbadox, chlortetracycline, lincomycin, tiamulin, tylosin and valnemulin. The MIC of each antimicrobial against L. intracellularis was determined using a tissue culture system and was identified as the lowest concentration that inhibited 99% of L. intracellularis growth, as compared to the antimicrobial-free control. Each antimicrobial concentration was evaluated for both intracellular and extracellular activity against L. intracellularis, an obligately intracellular bacterium. When tested for intracellular activity, carbadox, tiamulin, and valnemulin were the most active antimicrobials with MICs of < or =0.5microg/ml. Tylosin (MICs ranging from 0.25 to 32microg/ml) and chlortetracycline (MICs ranging from 0.125 to 64microg/ml) showed intermediate activities and lincomycin (MICs ranging from 8 to >128mIcog/ml) showed the least activity. When tested for extracellular activity, valnemulin (MICs ranging from 0.125 to 4microg/ml) was the most active against most L. intracellularis isolates. Chlortetracycline (MICs ranging from 16 to 64microg/ml), tylosin (MICs ranging from 1 to >128microg/ml), and tiamulin (MICs ranging from 1 to 32microg/ml) showed intermediate activities. Lincomycin (MICs ranging from 32 to >128microg/ml) showed the least activity. Our in vitro results showed that each L. intracellularis isolate had a different antimicrobial sensitivity pattern and these data can be utilized as an in vitro guideline for the further antimicrobial evaluation of field L. intracellularis isolates.

  19. Resistance of Pseudomonas aeruginosa Isolates to Hydrogel Contact Lens Disinfection Correlates with Cytotoxic Activity

    PubMed Central

    Lakkis, Carol; Fleiszig, Suzanne M. J.

    2001-01-01

    One of the most common pathogens in infection of hydrogel contact lens wearers is Pseudomonas aeruginosa, which can gain access to the eye via contamination of the lens, lens case, and lens care solutions. Only one strain per species is used in current regulatory testing for the marketing of chemical contact lens disinfectants. The aim of this study was to determine whether P. aeruginosa strains vary in their susceptibility to hydrogel contact lens disinfectants. A method for rapidly screening bacterial susceptibility to contact lens disinfectants was developed, based on measurement of the MIC. The susceptibility of 35 P. aeruginosa isolates to two chemical disinfectants was found to vary among strains. MICs ranged from 6.25 to 100% for both disinfectants at 37°C, and a number of strains were not inhibited by a 100% disinfectant concentration in the lens case environment at room temperature (22°C). Resistance to disinfection appeared to be an inherent rather than acquired trait, since some resistant strains had been isolated prior to the introduction of the disinfectants and some susceptible P. aeruginosa strains could not be made more resistant by repeated disinfectant exposure. A number of P. aeruginosa strains which were comparatively more resistant to short-term disinfectant exposure also demonstrated the ability to grow to levels above the initial inoculum in one chemical disinfectant after long-term (24 to 48 h) disinfectant exposure. Resistance was correlated with acute cytotoxic activity toward corneal epithelial cells and with exsA, which encodes a protein that regulates cytotoxicity via a complex type III secretion system. These results suggest that chemical disinfection solutions may select for contamination with cytotoxic strains. Further investigation of the mechanisms and factors responsible for resistance may also lead to strategies for reducing adverse responses to contact lens wear. PMID:11283074

  20. The antimicrobial activity of heterotrophic bacteria isolated from the marine sponge Erylus deficiens (Astrophorida, Geodiidae)

    PubMed Central

    Graça, Ana Patrícia; Viana, Flávia; Bondoso, Joana; Correia, Maria Inês; Gomes, Luis; Humanes, Madalena; Reis, Alberto; Xavier, Joana R.; Gaspar, Helena; Lage, Olga M.

    2015-01-01

    Interest in the study of marine sponges and their associated microbiome has increased both for ecological reasons and for their great biotechnological potential. In this work, heterotrophic bacteria associated with three specimens of the marine sponge Erylus deficiens, were isolated in pure culture, phylogenetically identified and screened for antimicrobial activity. The isolation of bacteria after an enrichment treatment in heterotrophic medium revealed diversity in bacterial composition with only Pseudoalteromonas being shared by two specimens. Of the 83 selected isolates, 58% belong to Proteobacteria, 23% to Actinobacteria and 19% to Firmicutes. Diffusion agar assays for bioactivity screening against four bacterial strains and one yeast, revealed that a high number of the isolated bacteria (68.7%) were active, particularly against Candida albicans and Vibrio anguillarum. Pseudoalteromonas, Microbacterium, and Proteus were the most bioactive genera. After this preliminary screening, the bioactive strains were further evaluated in liquid assays against C. albicans, Bacillus subtilis and Escherichia coli. Filtered culture medium and acetone extracts from three and 5 days-old cultures were assayed. High antifungal activity against C. albicans in both aqueous and acetone extracts as well as absence of activity against B. subtilis were confirmed. Higher levels of activity were obtained with the aqueous extracts when compared to the acetone extracts and differences were also observed between the 3 and 5 day-old extracts. Furthermore, a low number of active strains was observed against E. coli. Potential presence of type-I polyketide synthases (PKS-I) and non-ribosomal peptide synthetases (NRPSs) genes were detected in 17 and 30 isolates, respectively. The high levels of bioactivity and the likely presence of associated genes suggest that Erylus deficiens bacteria are potential sources of novel marine bioactive compounds. PMID:25999928

  1. Comparison of seismic response of ordinary and base-isolated structures

    SciTech Connect

    Kuroda, T.; Kobatake, M. ); Seidensticker, R.W.; Chang, Y.W. )

    1992-01-01

    Seismic isolation is growing rapidly worldwide as a cost-effective and reliable design strategy for a wide range of critical and important facilities (e.g., hospitals, computer centers, etc.) Shimizu Corporation of Japan has a test facility at Tohoku University in Sendai, Japan. The test facility was constructed in 1986 and has two buildings: one is base isolated and the other is conventionally founded. The buildings are full-size, three-story reinforced concrete structures. The dimensions and construction of the superstructures are identical. For the past several years, Shimizu Corporation has installed a number of different isolation systems in the isolated building at the test facility to study the response of base isolation systems to actual earthquake motions. Argonne National Laboratory (ANL) has been deeply involved in the development of seismic isolation for use in nuclear facilities for the past decade. Using the funding and direction of the US Department of Energy (USDOE), ANL has been developing methodology needed to evaluate the usefulness and effectiveness of seismic isolation for advanced liquid metal-cooled reactors (LMRs). This paper compares the seismic responses of ordinary and base-isolated buildings. Earthquake records of significant importance from April 1989 to September 1991, after the installation of bearings have been analyzed. Numerical simulations of the building responses have been performed and correlated with earthquake observation data. It is hoped that the results of this study will provide guidelines for the future use of isolator bearings for mitigation of earthquake damages.

  2. Comparison of seismic response of ordinary and base-isolated structures

    SciTech Connect

    Kuroda, T.; Kobatake, M.; Seidensticker, R.W.; Chang, Y.W.

    1992-04-01

    Seismic isolation is growing rapidly worldwide as a cost-effective and reliable design strategy for a wide range of critical and important facilities (e.g., hospitals, computer centers, etc.) Shimizu Corporation of Japan has a test facility at Tohoku University in Sendai, Japan. The test facility was constructed in 1986 and has two buildings: one is base isolated and the other is conventionally founded. The buildings are full-size, three-story reinforced concrete structures. The dimensions and construction of the superstructures are identical. For the past several years, Shimizu Corporation has installed a number of different isolation systems in the isolated building at the test facility to study the response of base isolation systems to actual earthquake motions. Argonne National Laboratory (ANL) has been deeply involved in the development of seismic isolation for use in nuclear facilities for the past decade. Using the funding and direction of the US Department of Energy (USDOE), ANL has been developing methodology needed to evaluate the usefulness and effectiveness of seismic isolation for advanced liquid metal-cooled reactors (LMRs). This paper compares the seismic responses of ordinary and base-isolated buildings. Earthquake records of significant importance from April 1989 to September 1991, after the installation of bearings have been analyzed. Numerical simulations of the building responses have been performed and correlated with earthquake observation data. It is hoped that the results of this study will provide guidelines for the future use of isolator bearings for mitigation of earthquake damages.

  3. Antifungal activity of itraconazole and voriconazole against clinical isolates obtained from animals with mycoses.

    PubMed

    Okabayashi, Ken; Imaji, Mashio; Osumi, Takafumi; Murakami, Yoshihiko; Maruyama, Haruhiko; Kano, Rui; Hasegawa, Atsuhiko; Watanabe, Toshi

    2009-01-01

    Animal mycosis, particularly deep mycosis, is one of the most challenging conditions encountered by veterinarians. Pathogens causing mycotic infections in animals include fungi such as Cryptococcus neoformans, Candida spp., and Aspergillus spp. The antifungal drugs used for the treatment of deep mycoses in animals as well as humans are polyenes and azoles. However, the sensitivity of clinical isolates obtained from animals toward these drugs has rarely been assayed. In this study, the antifungal activities of itraconazole and voriconazole against clinical isolates of C. neoformans, Candida spp., and A. fumigatus isolated from animals with mycoses were examined using the broth microdilution method performed according to the guidelines provided by the Clinical and Laboratory Standards Institute. The minimum inhibitory concentrations (MICs) of itraconazole toward the C. neoformans, Candida spp., and A. fumigatus isolates were 0.125 - 1, 0.125 - 2, and 0.25 - 2 microg/ml, respectively, and those of voriconazole were 0.0625 - 0.5, < or =0.0313 - 0.0625, and 0.0625 - 1 microg/ml, respectively. The results of the MIC analyses implied that the fungal isolates obtained from infected animals exhibit an equivalent degree of susceptibility to itraconazole and voriconazole, as is observed in the case of isolates obtained from humans. The appropriate antifungal therapeutic strategy for the treatment of mycoses in animals must be selected taking into consideration the host immune status and organ function as well as the in vitro sensitivity of the pathogens to antifungal drugs.

  4. Isolated gene encoding an enzyme with UDP-glucose pyrophosphorylase and phosphoglucomutase activities from Cyclotella cryptica

    DOEpatents

    Jarvis, Eric E.; Roessler, Paul G.

    1999-01-01

    The present invention relates to a cloned gene which encodes an enzyme, the purified enzyme, and the applications and products resulting from the use of the gene and enzyme. The gene, isolated from Cyclotella cryptica, encodes a multifunctional enzyme that has both UDP-glucose pyrophosphorylase and phosphoglucomutase activities.

  5. Melanostatin, a new melanin synthesis inhibitor. Production, isolation, chemical properties, structure and biological activity.

    PubMed

    Ishihara, Y; Oka, M; Tsunakawa, M; Tomita, K; Hatori, M; Yamamoto, H; Kamei, H; Miyaki, T; Konishi, M; Oki, T

    1991-01-01

    Melanostatin, a new antibiotic with melanin synthesis inhibitor activity, was isolated from the fermentation broth of Streptomyces clavifer No. N924-2. Its structure was determined by spectral analysis and degradation experiments. Melanostatin strongly inhibited melanin formation in Streptomyces bikiniensis NRRL B-1049 and B16 melanoma cells.

  6. The diversity and antimicrobial activity of Preussia sp. endophytes isolated from Australian dry rainforests.

    PubMed

    Mapperson, Rachel R; Kotiw, Michael; Davis, Rohan A; Dearnaley, John D W

    2014-01-01

    Limited knowledge currently exists regarding species diversity and antimicrobial activity of endophytic isolates of Preussia within Australia. This report describes endophytic Preussia species that were identified through molecular analysis of the internal transcribed spacer region. Screening for antimicrobial secondary metabolites was determined by testing crude ethyl acetate (EtOAc) extracts derived from fungal mycelia against a panel of ATCC type strains which included Bacillus cereus, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, Serratia marcescens, methicillin-resistant Staphylococcus aureus (MRSA) and the opportunist yeast pathogen Candida albicans. Subsequently, high-performance liquid chromatography generated fractions of bioactive EtOAc extracts which were subject to confirmatory testing using the Clinical and Laboratory Standards Institute reference microdilution antimicrobial activity assay. A total of 18 Preussia were isolated from nine host plants with 6/18 having a <97 % sequence similarity to other known species in Genbank, suggesting that they are new species. In preliminary screening, 13/18 Preussia isolates revealed antimicrobial activity against at least one of the microbes tested, whilst 6/18 isolates, including 4/6 putative new species showed specific antimicrobial activity against MRSA and C. albicans. These results highlight the antimicrobial potential of Australian Preussia spp. and also the importance of Australian dry rainforests as an untapped repository of potentially significant bioactive compounds.

  7. Isolated gene encoding an enzyme with UDP-glucose pyrophosphorylase and phosphoglucomutase activities from Cyclotella cryptica

    DOEpatents

    Jarvis, E.E.; Roessler, P.G.

    1999-07-27

    The present invention relates to a cloned gene which encodes an enzyme, the purified enzyme, and the applications and products resulting from the use of the gene and enzyme. The gene, isolated from Cyclotella cryptica, encodes a multifunctional enzyme that has both UDP-glucose pyrophosphorylase and phosphoglucomutase activities. 8 figs.

  8. Antioxidant and Antiplasmodial Activities of Bergenin and 11-O-Galloylbergenin Isolated from Mallotus philippensis

    PubMed Central

    Khan, Hamayun; Amin, Hazrat; Ullah, Asad; Saba, Sumbal; Rafique, Jamal; Khan, Khalid; Ahmad, Nasir; Badshah, Syed Lal

    2016-01-01

    Two important biologically active compounds were isolated from Mallotus philippensis. The isolated compounds were characterized using spectroanalytical techniques and found to be bergenin (1) and 11-O-galloylbergenin (2). The in vitro antioxidant and antiplasmodial activities of the isolated compounds were determined. For the antioxidant potential, three standard analytical protocols, namely, DPPH radical scavenging activity (RSA), reducing power assay (RPA), and total antioxidant capacity (TAC) assay, were adopted. The results showed that compound 2 was found to be more potent antioxidant as compared to 1. Fascinatingly, compound 2 displayed better EC50 results as compared to α-tocopherol while being comparable with ascorbic acid. The antiplasmodial assay data showed that both the compound exhibited good activity against chloroquine sensitive strain of Plasmodium falciparum (D10) and IC50 values were found to be less than 8 μM. The in silico molecular docking analyses were also performed for the determination of binding affinity of the isolated compounds using P. falciparum proteins PfLDH and Pfg27. The results showed that compound 2 has high docking score and binding affinity to both protein receptors as compared to compound 1. The demonstrated biological potentials declared that compound 2 could be the better natural antioxidant and antiplasmodial candidate. PMID:26998192

  9. Antioxidant and Antiplasmodial Activities of Bergenin and 11-O-Galloylbergenin Isolated from Mallotus philippensis.

    PubMed

    Khan, Hamayun; Amin, Hazrat; Ullah, Asad; Saba, Sumbal; Rafique, Jamal; Khan, Khalid; Ahmad, Nasir; Badshah, Syed Lal

    2016-01-01

    Two important biologically active compounds were isolated from Mallotus philippensis. The isolated compounds were characterized using spectroanalytical techniques and found to be bergenin (1) and 11-O-galloylbergenin (2). The in vitro antioxidant and antiplasmodial activities of the isolated compounds were determined. For the antioxidant potential, three standard analytical protocols, namely, DPPH radical scavenging activity (RSA), reducing power assay (RPA), and total antioxidant capacity (TAC) assay, were adopted. The results showed that compound 2 was found to be more potent antioxidant as compared to 1. Fascinatingly, compound 2 displayed better EC50 results as compared to α-tocopherol while being comparable with ascorbic acid. The antiplasmodial assay data showed that both the compound exhibited good activity against chloroquine sensitive strain of Plasmodium falciparum (D10) and IC50 values were found to be less than 8 μM. The in silico molecular docking analyses were also performed for the determination of binding affinity of the isolated compounds using P. falciparum proteins PfLDH and Pfg27. The results showed that compound 2 has high docking score and binding affinity to both protein receptors as compared to compound 1. The demonstrated biological potentials declared that compound 2 could be the better natural antioxidant and antiplasmodial candidate.

  10. Isolation of exocellular polymer from Zoogloea strains MP6 and 106 and from activated sludge.

    PubMed

    Farrah, S R; Unz, R F

    1976-07-01

    Exocellular polymer was isolated from zoogloeae of Zoogloea strains MP6 and 106 and from activated sludge flocs by blending samples with phosphate buffer and precipitation of solubilized polymer with cetyltrimethylammonium bromide. Samples of polymer from these sources were similar and yielded amino sugars as the principal components after acid hydrolysis.

  11. Complete genome of Bacillus sp. Pc3 isolated from the Antarctic seawater with antimicrobial activity.

    PubMed

    Guo, Wenbin; Cui, Pengfei; Chen, Xinhua

    2015-04-01

    Bacillus sp. Pc3 was isolated from the Antarctic seawater with strong antifungal activity against several plant pathogenic fungi. Here, we report the complete sequence of the 3.9-Mbp genome of this strain. The genome sequence may provide fundamental molecular information on elucidating the metabolic pathway of antimicrobial compounds in this strain.

  12. ISOLATION AND PARTIAL CHARACTERIZATION OF AN ACID PHOSPHATASE ACTIVITY FROM SPIRODELA OLIGORHIZA

    EPA Science Inventory

    An acid phosphatase activity from the aquatic plant Spirodela oligorhiza (duckweed) was isolated and partially characterized. S. oligorhiza was grown in a hydroponic growth medium, harvested, and ground up in liquid nitrogen. The ground plant material was added to a biological ...

  13. Pharmacodynamic studies on the isolated active fraction of Acacia farnesiana (L.) willd

    PubMed Central

    Kingsley, Bino; Kayarohanam, Saminathan; Brindha, Pemaiah; Subramoniam, Appian

    2014-01-01

    Background: Acacia farnesiana is a medicinal plant that grows throughout tropical parts of Indian subcontinent, particularly in sandy soils of river beds in Northern India. The objective of the present study was to evaluate the anti-hyperglycemic activity of the extracts using glucose tolerance test. Isolation of an active fraction (AF) from the active extract (water extract) using alcohol precipitation and to get insight to the mechanism of action of the AF of A. farnesiana. Materials and Methods: Glucose uptake by isolated rat diaphragm of the AF was performed. Further the effect of release of Insulin from isolated and cultured pancreatic β-cell was determined. Besides, effect of oral administration of the AF was compared with that of intraperitonial administration. The effect of AF on serum glucose levels in orally glucose loaded rats was compared with that of intraperitoneal glucose loaded rats. Results: The water extract significantly lowered the blood glucose level. When precipitated with alcohol, the activity was found in the soluble fraction. Glucose uptake in the isolated rat hemidiaphragm, was increased by the AF at 40 μg/ml concentration, the AF did not significantly influence insulin release from cultured islets. The AF was found to be effective in orally glucose loaded in contrast to intraperitonial route. Conclusion: Our findings suggest that this plant is promising for further studies leading to the development of valuable medicine for diabetes. PMID:24991104

  14. Using activity-based costing in surgery.

    PubMed

    Grandlich, Cheryl

    2004-01-01

    ACTIVITY-BASED COSTING is an accounting technique that allows organizations to determine actual costs associated with their services based on the resources they consume. THIS TECHNIQUE can be used in a variety of ways, including targeting high-cost activities, forecasting financial baselines, and supporting resource allocation. FOUR STEPS should be followed when applying activity-based costing to surgical procedures. THIS ARTICLE explores how Froedtert Memorial Lutheran Hospital, Milwaukee, used activity-based costing.

  15. In vitro activity of sparfloxacin (CI-978; AT-4140) against clinical isolates from cancer patients.

    PubMed Central

    Rolston, K V; Nguyen, H; Messer, M; LeBlanc, B; Ho, D H; Bodey, G P

    1990-01-01

    The in vitro activity of sparfloxacin, a new quinolone, was compared with those of ciprofloxacin and fleroxacin against gram-positive and gram-negative bacteria, greater than 90% of which were isolated from blood culture specimens of cancer patients. Sparfloxacin was extremely active against Acinetobacter species, Aeromonas hydrophila, Citrobacter diversus, Enterobacter species, Escherichia coli, Klebsiella species, Proteus vulgaris, and Serratia marcescens (inhibiting greater than 90% of these isolates at a concentration of 0.5 microgram/ml) and moderately active against Pseudomonas species, other Proteus species, and Citrobacter freundii. Sparfloxacin inhibited greater than 90% of staphylococci (including methicillin-resistant and coagulase-negative strains) at a concentration of 0.12 microgram/ml and greater than 90% of streptococci (including Streptococcus pneumoniae) at a concentration of 1.0 microgram/ml. It was also active against Bacillus cereus, Enterococcus species, and Corynebacterium jeikeium, organisms that have become fairly common in cancer patients. PMID:2127348

  16. Antioxidant, antimicrobial and tyrosinase inhibitory activities of xanthones isolated from Artocarpus obtusus F.M. Jarrett.

    PubMed

    Hashim, Najihah Mohd; Rahmani, Mawardi; Ee, Gwendoline Cheng Lian; Sukari, Mohd Aspollah; Yahayu, Maizatulakmal; Amin, Muhamad Aizat Mohd; Ali, Abd Manaf; Go, Rusea

    2012-05-21

    One of the most promising plants in biological screening test results of thirteen Artocarpus species was Artocarpus obtusus FM Jarrett and detailed phytochemical investigation of powdered dried bark of the plant has led to the isolation and identification of three xanthones; pyranocycloartobiloxanthone A (1), dihydroartoindonesianin C (2) and pyranocycloartobiloxanthone B (3). These compounds were screened for antioxidant, antimicrobial and tyrosinase inhibitory activities. Pyranocycloartobiloxanthone A (1) exhibited a strong free radical scavenger towards DPPH free radicals with IC50 value of 2 µg/mL with prominent discoloration observed in comparison with standard ascorbic acid, α-tocopherol and quercetin, The compound also exhibited antibacterial activity against methicillin resistant Staphylococcus aureus (ATCC3359) and Bacillus subtilis (clinically isolated) with inhibition zone of 20 and 12 mm, respectively. However the other two xanthones were found to be inactive. For the tyrosinase inhibitory activity, again compound (1) displayed strong activity comparable with the standard kojic acid.

  17. Isolation and antioxidant activity of zeylaniin A, a new macrocyclic ellagitannin from Syzygium zeylanicum leaves.

    PubMed

    Nomi, Yuri; Shimizu, Saki; Sone, Yasuko; Tuyet, Mai Truong; Gia, Tien Pham; Kamiyama, Masumi; Shibamoto, Takayuki; Shindo, Kazutoshi; Otsuka, Yuzuru

    2012-10-17

    Methanol extract obtained from Syzygium zeylanicum leaves exhibited potent antioxidant activity. The water extract obtained from this methanol extract by sequential extraction with hexane, chloroform, ethylacetate, and n-butanol also showed the strongest antioxidant activity among extracts. This water extract was further fractionated by column chromatography with various concentrations of methanol solutions. Among the 6 resultant fractions, the fraction developed with 20% methanol exhibited the most potent antioxidant activity. The one peak among the three major HPLC peaks in this fraction was isolated and purified using a preparative HPLC. The structure of a pure compound was elucidated as a novel macrocyclic ellagitannin using a (1)H/(13)C NMR and a high-resolution electrospray ionization mass spectrometer. This newly isolated compound, which was named zeylaniin A, exhibited potent antioxidant activities in the assays of DPPH, oxygen radical absorbance capacity, and malonadehyde/gas chromatography. S. zeylanicum leaves can be a possible source of natural antioxidants.

  18. Isolation of a New Mexican Strain of Bacillus subtilis with Antifungal and Antibacterial Activities

    PubMed Central

    Basurto-Cadena, M. G. L.; Vázquez-Arista, M.; García-Jiménez, J.; Salcedo-Hernández, R.; Bideshi, D. K.; Barboza-Corona, J. E.

    2012-01-01

    Although several strains of B. subtilis with antifungal activity have been isolated worldwide, to date there are no published reports regarding the isolation of a native B. subtilis strain from strawberry plants in Mexico. A native bacterium (Bacillus subtilis 21) demonstrated in vitro antagonistic activity against different plant pathogenic fungi. Under greenhouse conditions, it was shown that plants infected with Rhizoctonia solani and Fusarium verticillioides and treated with B. subtilis 21 produced augment in the number of leaves per plant and an increment in the length of healthy leaves in comparison with untreated plants. In addition, B. subtilis 21 showed activity against pathogenic bacteria. Secreted proteins by B. subtilis 21 were studied, detecting the presence of proteases and bacteriocin-like inhibitor substances that could be implicated in its antagonistic activity. Chitinases and zwittermicin production could not be detected. Then, B. subtilis 21 could potentially be used to control phytopathogenic fungi that infect strawberry plants. PMID:22593682

  19. Isolation of a new Mexican strain of Bacillus subtilis with antifungal and antibacterial activities.

    PubMed

    Basurto-Cadena, M G L; Vázquez-Arista, M; García-Jiménez, J; Salcedo-Hernández, R; Bideshi, D K; Barboza-Corona, J E

    2012-01-01

    Although several strains of B. subtilis with antifungal activity have been isolated worldwide, to date there are no published reports regarding the isolation of a native B. subtilis strain from strawberry plants in Mexico. A native bacterium (Bacillus subtilis 21) demonstrated in vitro antagonistic activity against different plant pathogenic fungi. Under greenhouse conditions, it was shown that plants infected with Rhizoctonia solani and Fusarium verticillioides and treated with B. subtilis 21 produced augment in the number of leaves per plant and an increment in the length of healthy leaves in comparison with untreated plants. In addition, B. subtilis 21 showed activity against pathogenic bacteria. Secreted proteins by B. subtilis 21 were studied, detecting the presence of proteases and bacteriocin-like inhibitor substances that could be implicated in its antagonistic activity. Chitinases and zwittermicin production could not be detected. Then, B. subtilis 21 could potentially be used to control phytopathogenic fungi that infect strawberry plants.

  20. Isolation and Characterization of Electrochemically Active Subsurface Delftia and Azonexus Species

    PubMed Central

    Jangir, Yamini; French, Sarah; Momper, Lily M.; Moser, Duane P.; Amend, Jan P.; El-Naggar, Mohamed Y.

    2016-01-01

    Continental subsurface environments can present significant energetic challenges to the resident microorganisms. While these environments are geologically diverse, potentially allowing energy harvesting by microorganisms that catalyze redox reactions, many of the abundant electron donors and acceptors are insoluble and therefore not directly bioavailable. Extracellular electron transfer (EET) is a metabolic strategy that microorganisms can deploy to meet the challenges of interacting with redox-active surfaces. Though mechanistically characterized in a few metal-reducing bacteria, the role, extent, and diversity of EET in subsurface ecosystems remains unclear. Since this process can be mimicked on electrode surfaces, it opens the door to electrochemical techniques to enrich for and quantify the activities of environmental microorganisms in situ. Here, we report the electrochemical enrichment of microorganisms from a deep fractured-rock aquifer in Death Valley, CA, USA. In experiments performed in mesocosms containing a synthetic medium based on aquifer chemistry, four working electrodes (WEs) were poised at different redox potentials (272, 373, 472, 572 mV vs. SHE) to serve as electron acceptors, resulting in anodic currents coupled to the oxidation of acetate during enrichment. The anodes were dominated by Betaproteobacteria from the families Comamonadaceae and Rhodocyclaceae. A representative of each dominant family was subsequently isolated from electrode-associated biomass. The EET abilities of the isolated Delftia strain (designated WE1-13) and Azonexus strain (designated WE2-4) were confirmed in electrochemical reactors using WEs poised at 522 mV vs. SHE. The rise in anodic current upon inoculation was correlated with a modest increase in total protein content. Both genera have been previously observed in mixed communities of microbial fuel cell enrichments, but this is the first direct measurement of their electrochemical activity. While alternate

  1. [Characteristics of microbial community structure during isolation of electrical active bacteria].

    PubMed

    Wang, Min; Zhao, Yang- Guo; Lu, Shan-Shan

    2014-10-01

    To investigate the effect of selective culturing on microorganisms and functional role of electrical active bacteria in biofilm, some exoelectrogens were isolated from microbial fuel cell (MFC) anodic biofilm using Hungate roll-tube technique with iron oxide as indicator. At the same time, the dynamics of the microbial community structure was monitored during the pure culture isolation. The results show that maximum voltages of MFCs feeding with lactic acid, acetic acid and steroid wastewater are 0.57, 0.60 and 0.40 V respectively. The dominant bacteria isolated from seed sludge and anodic films feeding with acetate and lactate belong to phylum Proteobacteria; while steroid wastewater contains relative high diversity of bacteria, i. e. Proteobacteria, Firmicutes and Bacteroidetes. After enriching and culturing, two bacteria were consequently obtained, which shared the highest similarity with Enterobacter ludwigii and Citrobacter freundii respectively. When inoculated in MFC with lactic acid as the substrate, they produced maximum voltage of 0.10 and 0.17 V individually. This study shows that electrical active bacteria can be isolated from the MFC anodic biofilm using anaerobic gradient dilution culture techniques with iron oxide as indicator. Microbial community structure presents markedly shifting during the bacteria isolation owing to its selectivity.

  2. Analysis and minimization of power flow in a mechanical vibration isolation system using a hybrid (active/passive) approach

    NASA Astrophysics Data System (ADS)

    Herdic, Peter C.; Houston, Brian H.; Corsaro, Robert D.; Judge, John A.

    2002-11-01

    Implementation of active control techniques in mechanical vibration isolation systems has been a challenging problem for a number of years where numerous physical control laws have been explored. An energy-based approach to the problem involving the energy transfer or power flow through the mount into the base structure is a first-principles approach to developing control laws and evaluating the system performance. A lumped-parameter model of a passive-active hybrid isolation mount has been developed and validated with experimental data. The mount device has a conventional passive compliant spring, embedded force and velocity sensors, and a piezoceramic actuation layer. This study investigates a complete set of possible layer configurations, that is, the optimal placement of sensors and actuator relative to the passive compliant isolator element. A number of different local physical control laws are examined and the level of power flow through the mount is used to evaluate the performance for the matrix of possible implementations. These results will be discussed with particular emphasis placed on the optimal control configuration and laws, and the related physics. a)Also with SFA, Inc., Largo, MD 20774.

  3. Experimental Immunization Based on Plasmodium Antigens Isolated by Antibody Affinity

    PubMed Central

    Kamali, Ali N.; Marín-García, Patricia; Azcárate, Isabel G.; Puyet, Antonio; Diez, Amalia; Bautista, José M.

    2015-01-01

    Vaccines blocking malaria parasites in the blood-stage diminish mortality and morbidity caused by the disease. Here, we isolated antigens from total parasite proteins by antibody affinity chromatography to test an immunization against lethal malaria infection in a murine model. We used the sera of malaria self-resistant ICR mice to lethal Plasmodium yoelii yoelii 17XL for purification of their IgGs which were subsequently employed to isolate blood-stage parasite antigens that were inoculated to immunize BALB/c mice. The presence of specific antibodies in vaccinated mice serum was studied by immunoblot analysis at different days after vaccination and showed an intensive immune response to a wide range of antigens with molecular weight ranging between 22 and 250 kDa. The humoral response allowed delay of the infection after the inoculation to high lethal doses of P. yoelii yoelii 17XL resulting in a partial protection against malaria disease, although final survival was managed in a low proportion of challenged mice. This approach shows the potential to prevent malaria disease with a set of antigens isolated from blood-stage parasites. PMID:26539558

  4. Magnetophoretic-based microfluidic device for DNA isolation.

    PubMed

    Hale, C; Darabi, J

    2014-07-01

    This paper presents a continuous flow microfluidic device for the separation of DNA from blood using magnetophoresis for biological applications and analysis. This microfluidic bio-separation device has several benefits, including decreased sample handling, smaller sample and reagent volumes, faster isolation time, and decreased cost to perform DNA isolation. One of the key features of this device is the use of short-range magnetic field gradients, generated by a micro-patterned nickel array on the bottom surface of the separation channel. In addition, the device utilizes an array of oppositely oriented, external permanent magnets to produce strong long-range field gradients at the interfaces between magnets, further increasing the effectiveness of the device. A comprehensive simulation is performed using COMSOL Multiphysics to study the effect of various parameters on the magnetic flux within the separation channel. Additionally, a microfluidic device is designed, fabricated, and tested to isolate DNA from blood. The results show that the device has the capability of separating DNA from a blood sample with a purity of 1.8 or higher, a yield of up to 33 μg of polymerase chain reaction ready DNA per milliliter of blood, and a volumetric throughput of up to 50 ml/h.

  5. Phytochemicals of apple peels: isolation, structure elucidation, and their antiproliferative and antioxidant activities.

    PubMed

    He, Xiangjiu; Liu, Rui Hai

    2008-11-12

    Bioactivity-guided fractionation of Red Delicious apple peels was used to determine the chemical identity of bioactive constituents, which showed potent antiproliferative and antioxidant activities. Twenty-nine compounds, including triterpenoids, flavonoids, organic acids and plant sterols, were isolated using gradient solvent fractionation, Diaion HP-20, silica gel, and ODS columns, and preparative HPLC. Their chemical structures were identified using HR-MS and 1D and 2D NMR. Antiproliferative activities of isolated pure compounds against HepG2 human liver cancer cells and MCF-7 human breast cancer cells were evaluated. On the basis of the yields of isolated flavonoids (compounds 18- 23), the major flavonoids in apple peels are quercetin-3-O-beta-D-glucopyranoside (compound 20, 82.6%), then quercetin-3-O-beta-D-galactopyranoside (compound 19, 17.1%), followed by trace amounts of quercetin (compound 18, 0.2%), (-)-catechin (compound 22), (-)-epicatechin (compound 23), and quercetin-3-O-alpha-L-arabinofuranoside (compound 21). Among the compounds isolated, quercetin (18) and quercetin-3-O-beta-D-glucopyranoside (20) showed potent antiproliferative activities against HepG2 and MCF-7 cells, with EC 50 values of 40.9 +/- 1.1 and 49.2 +/- 4.9 microM to HepG2 cells and 137.5 +/- 2.6 and 23.9 +/- 3.9 microM to MCF-7 cells, respectively. Six flavonoids (18-23) and three phenolic compounds (10, 11, and 14) showed potent antioxidant activities. Caffeic acid (10), quercetin (18), and quercetin-3-O-beta-D-arabinofuranoside (21) showed higher antioxidant activity, with EC 50 values of <10 microM. Most tested flavonoids and phenolic compounds had high antioxidant activity when compared to ascorbic acid and might be responsible for the antioxidant activities of apples. These results showed apple peel phytochemicals have potent antioxidant and antiproliferative activities.

  6. Verbascoside isolated from Lepechinia speciosa has inhibitory activity against HSV-1 and HSV-2 in vitro.

    PubMed

    Martins, Fernanda O; Esteves, Patricia F; Mendes, Gabriella S; Barbi, Nanci S; Menezes, Fabio S; Romanos, Maria T V

    2009-12-01

    Verbascoside has been isolated form L. speciosa after several different chromatographic methods. After its purification, the structure has been unequivocally established using modern spectroscopic techniques. As for the antiviral activity, the maximum non toxic concentration has been established and this concentration has been used in the anti herpes assay, in vitro. Mechanism of action for this molecule regarding the anti-herpes activity has been studied encompassing the following assays: virucidal activity, cellular receptor assay, penetration assay and intracellular assay, in order to understand the activity for this natural product.

  7. Activity of telithromycin against penicillin-resistant Streptococcus pneumoniae isolates recovered from French children with invasive and noninvasive infections.

    PubMed

    Bingen, Edouard; Doit, Catherine; Loukil, Chawki; Brahimi, Naima; Bidet, Philippe; Deforche, Dominique; Geslin, Pierre

    2003-07-01

    We compared the activities of telithromycin, erythromycin, azithromycin, josamycin, penicillin G, amoxicillin, cefpodoxime, and ceftriaxone against invasive and noninvasive non-penicillin-susceptible Streptococcus pneumoniae isolates recovered from children. Of the 186 isolates tested, 89% were positive for erm(B) by PCR. Telithromycin had the lowest MICs, with MICs at which 90% of the isolates tested are inhibited of 0.032 and 0.25 micro g/ml for erythromycin-sensitive and -resistant isolates, respectively.

  8. Comparison of antioxidant, anticholinesterase, and antidiabetic activities of three curcuminoids isolated from Curcuma longa L.

    PubMed

    Kalaycıoğlu, Zeynep; Gazioğlu, Işıl; Erim, F Bedia

    2017-03-13

    Antioxidant, anticholinesterase and antidiabetic activities of three curcuminoids isolated from the Curcuma longa were simultaneously tested and compared in this study. The highest antioxidant power was detected for curcumin with the applied methods. The drug potentials of curcuminoids for Alzheimer's disease were controlled. Bisdemethoxycurcumin (BDMC) showed substantial inhibitory activity. The activity of demethoxycurcumin (DMC) followed BDMC, whereas curcumin showed very little acetylcholinesterase inhibition activity. Antidiabetic activity of curcuminoids was evaluated by their α-glucosidase inhibitory activities. All curcuminoids show activities with decreasing order as BDMC > curcumin > DMC. The significant activities of BDMC compared to its isomers and examination of chemical structures of isomers might be a starting point in designing new drugs for Alzheimer's and Diabetes Mellitus.

  9. Spinach Thylakoid Polyphenol Oxidase : ISOLATION, ACTIVATION, AND PROPERTIES OF THE NATIVE CHLOROPLAST ENZYME.

    PubMed

    Golbeck, J H; Cammarata, K V

    1981-05-01

    Polyphenol oxidase activity (E.C. 1.14.18.1) has been found in two enzyme species isolated from thylakoid membranes of spinach chloroplasts. The proteins were released from the membrane by sonication and purified >900-fold by ammonium sulfate precipitation, gel filtration, and ion-exchange chromatography. The enzymes appear to be the tetramer and monomer of a subunit with a molecular weight of 42,500 as determined by lithium dodecyl sulfate gel electrophoresis. The higher molecular weight enzyme is the predominant form in freshly isolated preparations but on aging or further purification, the amount of lower molecular weight enzyme increases at the expense of the higher.Sonication releases polyphenol oxidase from the membrane largely in the latent state. C(18) fatty acids, especially linolenic acid, are potent activators of the enzymic activity. In the absence of added fatty acids, the isolated enzyme spontaneously, but slowly, activates with time.Purified polyphenol oxidase utilizes o-diphenols as substrates and shows no detectable levels of monophenol or p-diphenol oxidase activities. The K(m) values for 3,4-dihydroxyphenylalanine and O(2) are 6.5 and 0.065 millimolar, respectively. Suitable substrates include chlorogenic acid, catechol, caffeic acid, pyrogallol, and dopamine; however, the enzyme is substrate-inhibited by the last four at concentrations near their K(m) A large seasonal variation in polyphenol oxidase activity may result from a decrease in enzyme content rather than inhibition of the enzyme present.

  10. Cytotoxic and antimicrobial activities of endophytic fungi isolated from Bacopa monnieri (L.) Pennell (Scrophulariaceae)

    PubMed Central

    2014-01-01

    Background Endophytes, which reside in plant tissues, have the potential to produce novel metabolites with immense benefits for health industry. Cytotoxic and antimicrobial activities of endophytic fungi isolated from Bacopa monnieri (L.) Pennell were investigated. Methods Endophytic fungi were isolated from the Bacopa monnieri. Extracts from liquid cultures were tested for cytotoxicity against a number of cancer cell lines using the MTT assay. Antimicrobial activity was determined using the micro dilution method. Results 22% of the examined extracts showed potent (IC50 of <20 μg/ml) cytotoxic activity against HCT-116 cell line. 5.5%, 11%, 11% of the extracts were found to be cytotoxic for MCF-7, PC-3, and A-549 cell lines respectively. 33% extracts displayed antimicrobial activity against at least one test organism with MIC value 10–100 μg/ml. The isolate B9_Pink showed the most potent cytotoxic activity for all the cell lines examined and maximum antimicrobial activity against the four pathogens examined which was followed by B19. Conclusions Results indicated the potential for production of bioactive agents from endophytes of Bacopa monnieri. PMID:24512530

  11. Antibiotic susceptibility, antibacterial activity and characterisation of Enterococcus faecium strains isolated from breast milk

    PubMed Central

    Kıvanç, Sertaç Argun; Kıvanç, Merih; Yiğit, Tülay

    2016-01-01

    Enterococci, which have useful biotechnological applications, produce bacteriocins, including those that exert anti-Listerial activity. The present study aimed to determine the antibiotic susceptibility patterns and antimicrobial activity of Enterococcus faecium strains isolated from human breast milk. The strains were identified using carbohydrate fermentation tests and ribotyping. Subsequently, the antibacterial activity of the isolates was investigated, and the quantities of lactic acid and hydrogen peroxide produced, and the proteolytic activity of E. faecium, were determined. In addition, biofilm formation by E. faecium strains was assessed. E. faecium strains exhibited antimicrobial activity against food-borne and clinical bacterial isolates. Furthermore, following 24 h incubation, the tested strains exhibited resistance to a pH range of 2.0–9.5 and tolerance of bile acid, lysozyme activity and phenol. Supernatants of the E. faecium TM13, TM15, TM17 and TM18 strains were shown to be effective against Listeria monocytogenes, and were also resistant to heat. Further studies are required in order to determine whether certain strains of E. faecium may be used for the development of novel antibacterial agents. PMID:27602088

  12. In vitro activities of new and conventional antifungal agents against clinical Scedosporium isolates.

    PubMed

    Meletiadis, Joseph; Meis, Jacques F G M; Mouton, Johan W; Rodriquez-Tudela, Juan Luis; Donnelly, J Peter; Verweij, Paul E

    2002-01-01

    The susceptibilities of 13 clinical isolates of Scedosporium apiospermum and 55 clinical isolates of S. prolificans to new and conventional drugs belonging to three different classes of antifungal agents, the azoles (miconazole, itraconazole, voriconazole, UR-9825, posaconazole), the polyenes (amphotericin B, nystatin and liposomal nystatin), and allylamines (terbinafine), were studied by use of proposed standard M38-P of NCCLS. Low growth-inhibitory antifungal activities were found in vitro for most of the drugs tested against S. prolificans isolates, with the MICs at which 90% of isolates are inhibited (MIC(90)s) being >8 microg/ml; the MIC(90)s of voriconazole and UR-9825, however, were 4 microg/ml. S. apiospermum isolates were more susceptible in vitro, with the highest activity exhibited by voriconazole (MIC(90)s, 0.5 microg/ml), followed by miconazole (MIC(90)s, 1 microg/ml), UR-9825 and posaconazole (MIC(90)s, 2 microg/ml), and itraconazole (MIC(90)s, 4 microg/ml). The MICs of terbinafine, amphotericin B, and the two formulations of nystatin (for which no statistically significant differences in antifungal activities were found for the two species) for S. apiospermum isolates were high. Cross-resistance was observed among all the azoles except posaconazole and among all the polyenes except the lipid formulation. A distribution analysis was performed with the MICs of each drug and for each species. Bimodal and skewed MIC distributions were obtained, and cutoffs indicating the borders of different MIC subpopulations of the distributions were determined on the basis of the normal plot technique. These cutoffs were in many cases reproducible between 48 and 72 h.

  13. Analysis and optimisation for inerter-based isolators via fixed-point theory and algebraic solution

    NASA Astrophysics Data System (ADS)

    Hu, Yinlong; Chen, Michael Z. Q.; Shu, Zhan; Huang, Lixi

    2015-06-01

    This paper is concerned with the problem of analysis and optimisation of the inerter-based isolators based on a "uni-axial" single-degree-of-freedom isolation system. In the first part, in order to gain an in-depth understanding of inerter from the prospective of vibration, the frequency responses of both parallel-connected and series-connected inerters are analysed. In the second part, three other inerter-based isolators are introduced and the tuning procedures in both the H∞ optimisation and the H2 optimisation are proposed in an analytical manner. The achieved H2 and H∞ performance of the inerter-based isolators is superior to that achieved by the traditional dynamic vibration absorber (DVA) when the same inertance-to-mass (or mass) ratio is considered. Moreover, the inerter-based isolators have two unique properties, which are more attractive than the traditional DVA: first, the inertance-to-mass ratio of the inerter-based isolators can easily be larger than the mass ratio of the traditional DVA without increasing the physical mass of the whole system; second, there is no need to mount an additional mass on the object to be isolated.

  14. Time-kill determination of the bactericidal activity of telavancin and vancomycin against clinical methicillin-resistant Staphylococcus aureus isolates from cancer patients.

    PubMed

    Rolston, Kenneth Vi; Wang, Weiqun; Nesher, Lior; Smith, Jordan R; Rybak, Michael J; Prince, Randall A

    2017-04-01

    The bactericidal activity of vancomycin and telavancin was compared against 4 clinical methicillin-resistant Staphylococcus aureus isolates recently recovered from cancer patients, using minimum bactericidal concentration (MBC):MIC ratios and time-kill studies. All 4 isolates were susceptible to both agents based on individual MIC values. The 2 methodologies for assessing bactericidal activity produced variable results. Telavancin appeared to have somewhat better bactericidal activity than vancomycin based on narrower MBC:MIC ratios. However, based on the results of the time-kill studies, neither agent demonstrated reliable bactericidal activity (defined as a ≥3 log10 reduction of the starting inoculum at the end of 24hours) against these organisms. These findings might be of some therapeutic importance in certain clinical settings and/or specific patient populations (such as febrile neutropenic patients) in whom potent bactericidal activity is either desired or preferred.

  15. An anomaly detection and isolation scheme with instance-based learning and sequential analysis

    SciTech Connect

    Yoo, T. S.; Garcia, H. E.

    2006-07-01

    This paper presents an online anomaly detection and isolation (FDI) technique using an instance-based learning method combined with a sequential change detection and isolation algorithm. The proposed method uses kernel density estimation techniques to build statistical models of the given empirical data (null hypothesis). The null hypothesis is associated with the set of alternative hypotheses modeling the abnormalities of the systems. A decision procedure involves a sequential change detection and isolation algorithm. Notably, the proposed method enjoys asymptotic optimality as the applied change detection and isolation algorithm is optimal in minimizing the worst mean detection/isolation delay for a given mean time before a false alarm or a false isolation. Applicability of this methodology is illustrated with redundant sensor data set and its performance. (authors)

  16. A new approach to active vibration isolation for microgravity space experiments

    NASA Technical Reports Server (NTRS)

    Sinha, Alok; Kao, Chikuan K.; Grodsinsky, Carlos M.

    1990-01-01

    A new method was developed to design an active vibration isolation system for microgravity space experiments. This method yields the required controller transfer functions for a specified transmissibility ratio. Hence, it is a straightforward task to guarantee that the desired vibration isolation performance is achieved at each frequency. The theory for such a controller design was presented by considering a single degree of freedom system. In addition, the magnitude of the input required by the new method has been found to be less than that used by a standard phase lead/lag compensator.

  17. Biodegradation of didecyldimethylammonium chloride by Pseudomonas fluorescens TN4 isolated from activated sludge.

    PubMed

    Nishihara, T; Okamoto, T; Nishiyama, N

    2000-04-01

    Bacteria that degrade didecyldimethylammonium chloride (DDAC) were isolated from activated sludge from a municipal sewage treatment plant by enrichment culture with DDAC as a sole carbon source. One of the isolates, Pseudomonas fluorescens TN4, degraded DDAC to produce decyldimethylamine and subsequently, dimethylamine, as the intermediates. The TN4 strain also assimilated the other quaternary ammonium compounds (QACs), alkyltrimethyl- and alkylbenzyldimethyl-ammonium salts, but not alkylpyridinium salts. TN4 was highly resistant to these QACs and degraded them by an N-dealkylation process. These data mean that there are some QAC-resistant and QAC-degrading bacteria such as TN4 in the environment.

  18. Activity-guided isolation of cytotoxic bis-bibenzyl constituents from Dumortiera hirsuta.

    PubMed

    Toyota, Masao; Ikeda, Risa; Kenmoku, Hiromichi; Asakawa, Yoshinori

    2013-01-01

    Activity-guided fractionation of the ether extract of Dumortiera hirsute (Japanese liverwort), using cytotoxicity testing with cultured HL 60 and KB cells, resulted in the isolation of a new cytotoxic bis-bibenzyl compound, along with the two known bis-bibenzyls: isomarchantin C and isoriccardin C. The structural determination of the new bis-bibenzyl through extensive NMR spectral data indicated a derivative of marchantin A, which has been isolated from the liverwort Marchantia polymorpha. The cytotoxicity of the bis-bibenzyls was evaluated by the MTT (3-(4,5-di-methylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay using cultured HL 60 and KB cells.

  19. Isolation, characterization and hypolipidemic activity of ferulic acid in high-fat-diet-induced hyperlipidemia in laboratory rats

    PubMed Central

    Jain, Pankaj G.; Surana, Sanjay J.

    2016-01-01

    Prosopis cineraria (L.) Druce (Leguminosae) (syn. Prosopis spicigera L.) has antidiabetic and antioxidant potential. Earlier we reported its hypolipidemic activity obtained from ethanol extract (ET-PCF). Object of this work was to isolate ferulic acid (FA) from ET-PCF and evaluate hypolipidemic activity against high-fat diet (HFD)-induced hyperlipidemic laboratory rats. ET-PCF was subjected to flash column chromatography to isolate FA. The chemical structure of the isolated compound was elucidated by UV, IR, 1H NMR,13C NMR and LC-MS. Further, the antihyperlipidemic effect of FA (10, 20 and 40 mg/kg, p.o.) in HFD-induced hyperlipidemic rats was investigated. Hyperlipidemia was induced in male Sprague-Dawley rats by feeding with HFD for 60 days. Lipid parameters such as total cholesterol (TC), Low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG) levels were measured in serum and hepatic tissue. Hepatic oxido-nitrosative stress (SOD, GSH, MDA and NO) were also determined. Histological evaluation of liver tissue was carried out. The structure of the isolated compound was characterized based on spectral data and confirmed as FA. HFD induced an alteration in serum, and hepatic lipid profile (triglyceride, cholesterol, HDL, and LDL) was significantly restored (p < 0.001) by administration of FA (20 and 40 mg/kg, p.o.). The elevated level of oxido-nitrosative stress in liver was significantly reduced (p < 0.001) by FA (20 and 40 mg/kg, p.o.). Histological aberration induced in the liver after HFD ingestion were restored by FA administration. Ferulic acid isolated from ET-PCF showed hypolipidemic effects in HFD-induced hyperlipidemic rats via modulation of elevated oxido-nitrosative stress. PMID:28096790

  20. DNase I sensitivity of transcriptionally active genes in intact nuclei and isolated chromatin of plants.

    PubMed Central

    Spiker, S; Murray, M G; Thompson, W F

    1983-01-01

    We have investigated the DNase I sensitivity of transcriptionally active DNA sequences in intact nuclei and isolated chromatin from embryos of wheat (Triticum aestivum L.). Nuclei or isolated chromatin was incubated with DNase I, and the extent of DNA digestion was monitored as percentage acid solubility. The resistant DNA and DNA from sham-digested controls were used to drive reassociation reactions with cDNA populations corresponding to either total poly(A)+RNA from unimbibed wheat embryos or polysomal poly(A)+RNA from embryos that had imbibed for 3 hr. Sequences complementary to either probe were depleted in DNase I-resistant DNA from nuclei and from chromatin isolated under low-ionic-strength conditions. This indicates that transcriptionally active sequences are preferentially DNase I sensitive in plants. In chromatin isolated at higher ionic strength, cDNA complementary sequences were not preferentially depleted by DNase I treatment. Therefore, the chromatin structure that confers preferential DNase I sensitivity to transcriptionally active genes appears to be lost when the higher-ionic-strength method of preparation is used. Treatment of wheat nuclei with DNase I causes the release of four prominent nonhistone chromosomal proteins that comigrate with wheat high mobility group proteins on NaDodSO4 gels. Images PMID:6219388

  1. Antileishmanial activity of prenylated coumarins isolated from Ferulago angulata and Prangos asperula

    PubMed Central

    Sajjadi, Seyed Ebrahim; Eskandarian, Abbas-Ali; Shokoohinia, Yalda; Yousefi, Hosein-Ali; Mansourian, Marjan; Asgarian-Nasab, Hasan; Mohseni, Negar

    2016-01-01

    Leishmaniasis has a wide spectrum of signs and symptoms due to infection to numbers of Leishmania species and makes enormous mortality and morbidity. There are clues of antileishmanial effects of prenylated coumarins. Apiaceae family is one of the most important sources of coumarins. Air-dried aerial parts of Ferulago angulata and fruits of Prangos asperula were extracted with n-hexane, using a soxhlet apparatus. The solvents were evaporated under reduced pressure. Column chromatography and crystallization process resulted to isolation of three prenylated coumarins. 1H-nuclear magnetic resonance, electron ionization Mass and Infrared spectra were used for elucidation of isolated compounds. Leishmanicidal activity of isolated coumarins was assessed on Leishmania major strain (MRHO/IR/75/ER) for the first time. Suberosin epoxide and suberosin were isolated from aerial parts of F. angulata and osthol was extracted from grounded fruits of P. asperula. Osthol showed a significant antileishmanial effect on promastigotes in early hours of exposure with IC50 of 14.40 µg/mL but suberosin epoxide showed only a weak antileishmanial activity. IC50 of osthol and suberosin epoxide after 48 h were 10.79 and 54.0 µg/mL, respectively. Suberosin showed no remarkable effect in these concentrations. This is the first report on the pharmacological activity of suberosin epoxide. Substantial difference between efficacies of two isomers, osthol and suberosin remarks the importance of prenyl substituent location on C-8. PMID:27651813

  2. Phenol degrading ability of Rhodococcus pyrinidivorans and Pseudomonas aeruginosa isolated from activated sludge plants in South Africa.

    PubMed

    Kumari, Sheena; Chetty, Dereshen; Ramdhani, Nishani; Bux, Faizal

    2013-01-01

    Phenol, a common constituent in many industrial wastewaters is a major pollutant and has several adverse effects on the environment. The potential of various microorganisms to utilize phenol for their metabolic activity has been observed to be an effective means of remediating this toxic compound from the environment particularly wastewater. Five indigenous bacterial isolates (PD1-PD5) were obtained from phenol bearing industrial wastewater using the mineral salts medium. The isolates were further characterized based on their morphology, biochemical reactions and 16S rRNA phylogeny. The 16S rRNA sequence analysis using universal primers (27f/1492r) revealed that PD1, PD2, PD3 and PD4 were closely related to the actinomycete Rhodococcus pyrinidivorans (99%) and PD5 to Pseudomonas aeruginosa (99%). Growth kinetic patterns and phenol degradation abilities of the two representative isolates (PD1 and PD5) were also evaluated. Both the species were effective in utilizing phenol as the sole carbon source and could tolerate phenol concentrations of up to 500 to 600 mg/L. The ability of these isolates to utilize higher concentrations of phenol as their sole carbon source makes them potential candidates and better competitors in the bioremediation process.

  3. Modeling the behavior of an earthquake base-isolated building.

    SciTech Connect

    Coveney, V. A.; Jamil, S.; Johnson, D. E.; Kulak, R. F.; Uras, R. A.

    1997-11-26

    Protecting a structure against earthquake excitation by supporting it on laminated elastomeric bearings has become a widely accepted practice. The ability to perform accurate simulation of the system, including FEA of the bearings, would be desirable--especially for key installations. In this paper attempts to model the behavior of elastomeric earthquake bearings are outlined. Attention is focused on modeling highly-filled, low-modulus, high-damping elastomeric isolator systems; comparisons are made between standard triboelastic solid model predictions and test results.

  4. Analog isolated electronic dynamometer based on a magnetoresistive current sensor

    NASA Astrophysics Data System (ADS)

    Arcos Carrasco, C.; Ramírez Muñoz, D.; Ravelo Arias, S. I.; Sánchez Moreno, J.; Maset Sancho, E.; Garrigós Sirvent, A.

    2017-03-01

    In this work, an electronic system is presented to measure the force applied by a solenoid. The originality of the work is focused on the use of a magnetoresistive current sensor to provide the isolation barrier needed in the actual industrial plant where the solenoids are working. The design of the electronic system is presented as well as experimental measurements as a result of a calibration process showing a negligible hysteresis with that specific sensor. The magnetoresistive current sensor is used to develop transmission functions rather than playing its usual sensing roles.

  5. Anti-septic activity of α-cubebenoate isolated from Schisandra chinensis.

    PubMed

    Kook, Minsoo; Lee, Sung Kyun; Kim, Sang Doo; Lee, Ha Young; Hwang, Jae Sam; Choi, Young Whan; Bae, Yoe-Sik

    2015-06-01

    Sepsis is a life-threatening, infectious, systemic inflammatory disease. In this study, we investigated the therapeutic effect of α-cubebenoate, a novel compound isolated from Schisandra chinensis against polymicrobial sepsis in a cecal ligation and puncture (CLP) experimental model. Administration of α-cubebenoate strongly enhanced survival in the CLP model. α-cubebenoate administration also markedly blocked CLP-induced lung inflammation and increased bactericidal activity by enhancing phagocytic activity and hydrogen peroxide generation in mouse bone marrow-derived macrophages and neutrophils. Expression of two important inflammatory cytokines, IL-1β and IL-6, was strongly increased in the CLP model, and this was dramatically blocked by α-cubebenoate. Lymphocyte apoptosis and caspase-3 activation, which are associated with immune paralysis during sepsis, were markedly attenuated by α-cubebenoate. Taken together, our findings indicate that α-cubebenoate, a natural compound isolated from Schisandra chinensis, is a powerful potential anti-septic agent.

  6. Gene activation properties of a mouse DNA sequence isolated by expression selection.

    PubMed Central

    von Hoyningen-Huene, V; Norbury, C; Griffiths, M; Fried, M

    1986-01-01

    The MES-1 element was previously isolated from restricted total mouse cellular DNA by "expression selection"--the ability to reactivate expression of a test gene devoid of its 5' enhancer sequences. Mes-1 has been tested in long-term transformation and short-term CAT expression assays. In both assays MES-1 is active independent of orientation and at a distance when placed 5' to the test gene. The element is active with heterologous promoters and functions efficiently in both rat and mouse cells. MES-1 activates expression by increasing transcription from the test gene's own start (cap) site. Thus the expression selection technique can be used for the isolation of DNA sequences with enhancer-like properties from total cellular DNA. Images PMID:3016657

  7. In vitro activities of antimicrobial agents, alone and in combination, against Acinetobacter baumannii isolated from blood.

    PubMed

    Chang, S C; Chen, Y C; Luh, K T; Hsieh, W C

    1995-11-01

    In vitro activities of 15 antimicrobial agents against 90 strains of Acinetobacter baumannii isolated from blood cultures from hospitalized patients were determined using the agar dilution method. Imipenem, ofloxacin, and ciprofloxacin had the best antimicrobial activity with minimum inhibitory concentrations (MIC50s) of 0.25 mu g/ml and MIC90s of 0.5-1 mu g/ml. beta-lactam antibiotics other than imipenem had poor activity, with MIC50s ranging from 8 to 64 mu g/ml and MIC90s from 32 to > or = 256 mu g/ml. The checkerboard titration method was used to study the effects of combination of two antimicrobial agents. Combinations of ceftazidime, aztreonam, imipenem, or ciprofloxacin with amikacin showed either synergistic effects or partial synergistic effects for 40.9%-86.4% of 22 tested strains. The best in vitro activity was observed with the combination of imipenem and amikacin. No antagonistic effects were observed with the combination of imipenem and amikacin. Synergistic effects were confirmed by time-kill curve studies. In conclusion, imipenem, ofloxacin, and ciprofloxacin were the three most active agents against human blood isolates of A. baumannii. The combination of a beta-lactam or ciprofloxacin with amikacin was synergistic for some of the isolates.

  8. In vitro activities of natural products against oral Candida isolates from denture wearers

    PubMed Central

    2011-01-01

    Background Candida-associated denture stomatitis is a frequent infectious disease. Treatment of this oral condition is difficult because failures and recurrences are common. The aim of this study was to test the in vitro antifungal activity of pure constituents of essentials oils. Methods Eight terpenic derivatives (carvacrol, farnesol, geraniol, linalool, menthol, menthone, terpinen-4-ol, and α-terpineol), a phenylpropanoid (eugenol), a phenethyl alcohol (tyrosol) and fluconazole were evaluated against 38 Candida isolated from denture-wearers and 10 collection Candida strains by the CLSI M27-A3 broth microdilution method. Results Almost all the tested compounds showed antifungal activity with MIC ranges of 0.03-0.25% for eugenol and linalool, 0.03-0.12% for geraniol, 0.06-0.5% for menthol, α-terpineol and terpinen-4-ol, 0.03-0.5% for carvacrol, and 0.06-4% for menthone. These compounds, with the exception of farnesol, menthone and tyrosol, showed important in vitro activities against the fluconazole-resistant and susceptible-dose dependent Candida isolates. Conclusions Carvacrol, eugenol, geraniol, linalool and terpinen-4-ol were very active in vitro against oral Candida isolates. Their fungistatic and fungicidal activities might convert them into promising alternatives for the topic treatment of oral candidiasis and denture stomatitis. PMID:22118215

  9. [Antithrombotic and hemorrhagic activities of fucoidan isolated from Fucus evanescens brown algae].

    PubMed

    Drozd, N N; Miftakhova, N T; Savchik, E Iu; Kalinina, T B; Makarov, V A; Imbs, T I; Zviagintseva, T N; Kuznetsova, T A; Besednova, N N

    2011-01-01

    The antithrombotic and hemorrhagic activities of fucoidan with molecular weight within 20 - 40 kD isolation from Fucus evanescens seaweed have been investigated. The antithrombin activity of fucoidan is 41 +/- 9 aIIa IU/mg and the anti-factor Oà activity is 38 +/- 8 aOà IU/mg. The antithrombin and anti-factor Oà activities of plasma, antithrombotic activity (100% prevention of formation of a blood clot observed at a dose of 10 mg/kg), and hemorrhagic activity (to a lesser degree, than that of unfractionated heparin in comparable antithrombotic activity doses) increase as the doses of fucoidan increases from 2.5 to 10 mg/kg at intravenous injection in rats.

  10. [Evaluation of beta-glucuronidase activity for the isolation of diarrhea-causing Escherichia coli].

    PubMed

    Muto, T; Arai, K; Miyai, M

    1991-06-01

    To compare the isolating efficiency of diarrhea-causing Escherichia coli between Fluorocult agar plates, which reveal the beta-glucuronidase activity of E. coli, and a combination of SS and DHL agar plates, a total of 330 fecal specimens collected from outpatients were examined. Diarrhea-causing E. coli, identified by serological and toxigenic characters, were demonstrated in 52 samples. Among these specimens, 35 samples tested were positive on the Fluorocult agar plates, and 26 samples on the combination of SS and DHL agar plates. However, only 10 samples were positive on both the Fluorocult agar plates and the combination of SS and DHL agar plates. Thus, using Fluorocult agar plates for the isolation of diarrhea-causing E. coli in addition to the conventional SS and DHL agar plates will improve isolating efficacy.

  11. Active Vibration Isolation of Microgravity Experiments with Spring Umbilicals Using an Electrodynamic Actuator

    NASA Technical Reports Server (NTRS)

    Banerjee, B. B.; Allaire, P. E.; Grodsinsky, C. M.

    1996-01-01

    Microgravity experiments will require active vibration isolation in the low to mid frequency range of 0.1 Hz to 10 Hz. Approximately two orders of acceleration reduction (40 dB) will be required. Previous works have reported results for accelerations transmitted through the umbilical. This paper describes experimental and theoretical results for vibration isolation in one dimension (horizontal) where the simulated experiment is connected to the spacecraft by a spring umbilical. The experiment consisted of a spacecraft (shaker), experiment (mass), umbilical, accelerometer, control electronics, and Lorentz actuator. The experiment mass was supported in magnetic bearings to avoid any stiction problems. Acceleration feedback control was employed to obtain the vibration isolation. Three different spring umbilicals were employed. Acceleration reductions on the order of 40 dB were obtained over the frequency range of 0.1 Hz to 10 Hz. Good agreement was obtained between theory and experiment.

  12. Isolation, antimicrobial activity, and metabolites of fungus Cladosporium sp. associated with red alga Porphyra yezoensis.

    PubMed

    Ding, Ling; Qin, Song; Li, Fuchao; Chi, Xiaoyuan; Laatsch, Hartmut

    2008-03-01

    Cladosporium sp. isolate N5 was isolated as a dominant fungus from the healthy conchocelis of Porphyra yezoensis. In the re-infection test, it did not cause any pathogenic symptoms in the alga. Twenty-one cultural conditions were chosen to test its antimicrobial activity in order to obtain the best condition for large-scale fermentation. Phenylacetic acid, p-hydroxyphenylethyl alcohol, and L-beta-phenyllactic acid were isolated from the crude extract as strong antimicrobial compounds and they are the first reported secondary metabolites for the genus Cladosporium. In addition, the Cladosporium sp. produced the reported Porphyra yezoensis growth regulators phenylacetic acid and p-hydroxyphenylacetic acid. No cytotoxicity was found in the brine shrimp lethality test, which indicated that the environmental-friendly Cladosporium sp. could be used as a potential biocontrol agent to protect the alga from pathogens.

  13. Anti-diabetic activity of a mineraloid isolate, in vitro and in genetically diabetic mice.

    PubMed

    Deneau, Joel; Ahmed, Taufeeq; Blotsky, Roger; Bojanowski, Krzysztof

    2011-01-01

    Type II diabetes is a metabolic disease mediated through multiple molecular pathways. Here, we report anti-diabetic effect of a standardized isolate from a fossil material - a mineraloid leonardite - in in vitro tests and in genetically diabetic mice. The mineraloid isolate stimulated mitochondrial metabolism in human fibroblasts and this stimulation correlated with enhanced expression of genes coding for mitochondrial proteins such as ATP synthases and ribosomal protein precursors, as measured by DNA microarrays. In the diabetic animal model, consumption of the Totala isolate resulted in decreased weight gain, blood glucose, and glycated hemoglobin. To our best knowledge, this is the first description ever of a fossil material having anti-diabetic activity in pre-clinical models.

  14. Isolation of Insecticidal Constituent from Ruta graveolens and Structure-Activity Relationship Studies against Stored-Food Pests (Coleoptera).

    PubMed

    Jeon, Ju-Hyun; Lee, Sang-Guei; Lee, Hoi-Seon

    2015-08-01

    Isolates from essential oil extracted from the flowers and leaves of Ruta graveolens and commercial phenolic analogs were evaluated using fumigant and contact toxicity bioassays against adults of the stored-food pests Sitophilus zeamais, Sitophilus oryzae, and Lasioderma serricorne. The insecticidal activity of these compounds was then compared with that of the synthetic insecticide dichlorvos. To investigate the structure-activity relationships, the activity of 2-isopropyl-5-methylphenol and its analogs was examined against these stored-food pests. Based on the 50% lethal dose, the most toxic compound against S. zeamais was 3-isopropylephenol, followed by 2-isopropylphenol, 4-isopropylphenol, 5-isopropyl-2-methylphenol, 2-isopropyl-5-methylphenol, 3-methylphenol, and 2-methylphenol. Similar results were observed with phenolic compounds against S. oryzae. However, when 2-isopropyl-5-methylphenol isolated from R. graveolens oil and its structurally related analogs were used against L. serricorne, little or no insecticidal activity was found regardless of bioassay. These results indicate that introducing and changing the positions of functional groups in the phenol skeleton have an important effect on insecticidal activity of these compounds against stored-food pests.

  15. Rhizoxin analogs contribute to the biocontrol activity of a newly isolated pseudomonas strain.

    PubMed

    Takeuchi, Kasumi; Noda, Naomi; Katayose, Yuichi; Mukai, Yoshiyuki; Numa, Hisataka; Yamada, Kosumi; Someya, Nobutaka

    2015-03-01

    Two strains of Pseudomonas sp., Os17 and St29, were newly isolated from the rhizosphere of rice and potato, respectively, by screening for 2,4-diacetylphloroglucinol producers. These strains were found to be the same species and were the closest to but different from Pseudomonas protegens among the sequenced pseudomonads, based on 16S ribosomal RNA gene and whole-genome analyses. Strain Os17 was as effective a biocontrol agent as reported for P. protegens Cab57, whereas strain St29 was less effective. The whole-genome sequences of these strains were obtained: the genomes are organized into a single circular chromosome with 6,885,464 bp, 63.5% G+C content, and 6,195 coding sequences for strain Os17; and with 6,833,117 bp, 63.3% G+C content, and 6,217 coding sequences for strain St29. Comparative genome analysis of these strains revealed that the complete rhizoxin analog biosynthesis gene cluster (approximately 79 kb) found in the Os17 genome was absent from the St29 genome. In an rzxB mutant, which lacks the polyketide synthase essential for the production of rhizoxin analogs, the growth inhibition activity against fungal and oomycete pathogens and the plant protection efficacy were attenuated compared with those of wild-type Os17. These findings suggest that rhizoxin analogs are important biocontrol factors of this strain.

  16. Development of a Simulation Capability for the Space Station Active Rack Isolation System

    NASA Technical Reports Server (NTRS)

    Johnson, Terry L.; Tolson, Robert H.

    1998-01-01

    To realize quality microgravity science on the International Space Station, many microgravity facilities will utilize the Active Rack Isolation System (ARIS). Simulation capabilities for ARIS will be needed to predict the microgravity environment. This paper discusses the development of a simulation model for use in predicting the performance of the ARIS in attenuating disturbances with frequency content between 0.01 Hz and 10 Hz. The derivation of the model utilizes an energy-based approach. The complete simulation includes the dynamic model of the ISPR integrated with the model for the ARIS controller so that the entire closed-loop system is simulated. Preliminary performance predictions are made for the ARIS in attenuating both off-board disturbances as well as disturbances from hardware mounted onboard the microgravity facility. These predictions suggest that the ARIS does eliminate resonant behavior detrimental to microgravity experimentation. A limited comparison is made between the simulation predictions of ARIS attenuation of off-board disturbances and results from the ARIS flight test. These comparisons show promise, but further tuning of the simulation is needed.

  17. Biodegradation of geosmin in drinking water by novel bacteria isolated from biologically active carbon.

    PubMed

    Zhou, Beihai; Yuan, Rongfang; Shi, Chunhong; Yu, Liying; Gu, Junnong; Zhang, Chunlei

    2011-01-01

    Three strains of Gram-negative bacteria capable of removing geosmin from drinking water were isolated from biologically active carbon and identified to be Chryseobacterium sp., Sinorhizobium sp. and Stenotrophomonas sp. based on physio-biochemistry analysis and 16S rRNA gene sequence analysis. Removal efficiencies of 2 mg/L geosmin in mineral salts medium were 84.0%, 80.2% and 74.4% for Chryseobacterium sp., Sinorhizobium sp. and Stenotrophomonas sp., respectively, while removal efficiencies of 560 ng/L geosmin in filter influent were 84.8%, 82.3% and 82.5%, respectively. The biodegradation of geosmin was determined to be a pseudo first-order reaction, with rate constants at 2 mg/L and 560 ng/L being 0.097 and 0.086 day(-1), 0.089 and 0.084 day(-1), 0.074 and 0.098 day(-1) for the above mentioned degraders, respectively. The biomass of culture in the presence of geosmin was much higher than that in the absence of geosmin.

  18. Antibacterial Activity of the Isolation Ethyl Acetate-Soluble Extract Noni Fruit (Morindra citrifolia L.) against Meat Bacterial Decay

    NASA Astrophysics Data System (ADS)

    Nugraheni, E. R.; Nurrakhman, M. B. E.; Munawaroh, H.; Saputri, L.

    2017-02-01

    Noni (Morindra citrifolia L.) is native to Indonesia which have medicinal properties. One of them as an antibacterial. This study aims to determine the antibacterial activity of isolates from the ethanol extract noni fruit to bacterial decay meat is Bacillus licheniformis, Klebsiella pneumonia, Bacillus alvei, Acinetobacter calcoaceticus, and Staphylococcus saprophyticus. The extraction process using the maceration method, and then made a partition by centrifugation ethyl acetate. Soluble part partition showed bacterial growth inhibition activity of the strong to very strong. Furthermore, the ethyl acetate soluble partition on preparative thin layer chromatography produced 5 isolates. Isolates obtained antibacterial activity test performed with a concentration of 20% and 30%. The results of antibacterial test against bacteria test isolates, showing isolates A can not inhibit the growth of bacteria, isolates B and C have medium activity and strong, isolates D and E isolates have activity against bacteria that were tested. MIC and MBC test results showed that the isolates B gives an inhibitory effect (bacteriostatic) against all bacteria. Content analysis of compounds by TLC using the reagents cerium (IV) sulfate indicates a phenol group. Isolates B contains a major compound which can be used as an antibacterial candidate in food preservation replace chemical preservatives.

  19. Actinomycetes from solitary wasp mud nest and swallow bird mud nest: isolation and screening for their antibacterial activity.

    PubMed

    Kumar, Vijay; Bharti, Alpana; Gupta, Vivek Kumar; Gusain, Omprakash; Bisht, Gajraj Singh

    2012-03-01

    The aim of this study was to isolate and screen actinomycetes from solitary wasp and swallow bird mud nests for antimicrobial activity. The actinomycetes were isolated from soil of nests of solitary wasp and swallow bird, and identified on the basis of morphological characteristics and molecular biological methods. A total of 109 actinomycetal isolates were obtained from 12 soil samples (6 from each habitat) using two media. The highest number of actinomycetes were recovered on Humic acid vitamin agar media (65.13%, n = 71) as compared to actinomycetes isolation agar media (34.86%, n = 38). The antimicrobial activity of actinomycetes isolates was determined using the agar plug method. Among 109 isolates, 51 isolates (46.78%) showed antibacterial activity by agar plug assay. The morphological and molecular characteristics confirmed that the most of active isolates in both sample belonged to the genus Streptomyces, the other potential genera like Streptosporangium, Actinomadura, Saccharopolyspora, Thermoactinomycetes and Nocardia were also recovered, but in a low frequency. The isolates designated as 8(1), BN-6, MN 2(6), MN 2(7) and MN 9(V) showed most promising activity against various drug resistant bacterial pathogens. It seems that the promising isolates from these unusual/unexplored habitats may prove to be an important step in development of drug for treating multi-drug resistant bacterial pathogens.

  20. Isolation of novel ribozymes that ligate AMP-activated RNA substrates

    NASA Technical Reports Server (NTRS)

    Hager, A. J.; Szostak, J. W.

    1997-01-01

    BACKGROUND: The protein enzymes RNA ligase and DNA ligase catalyze the ligation of nucleic acids via an adenosine-5'-5'-pyrophosphate 'capped' RNA or DNA intermediate. The activation of nucleic acid substrates by adenosine 5'-monophosphate (AMP) may be a vestige of 'RNA world' catalysis. AMP-activated ligation seems ideally suited for catalysis by ribozymes (RNA enzymes), because an RNA motif capable of tightly and specifically binding AMP has previously been isolated. RESULTS: We used in vitro selection and directed evolution to explore the ability of ribozymes to catalyze the template-directed ligation of AMP-activated RNAs. We subjected a pool of 10(15) RNA molecules, each consisting of long random sequences flanking a mutagenized adenosine triphosphate (ATP) aptamer, to ten rounds of in vitro selection, including three rounds involving mutagenic polymerase chain reaction. Selection was for the ligation of an oligonucleotide to the 5'-capped active pool RNA species. Many different ligase ribozymes were isolated; these ribozymes had rates of reaction up to 0.4 ligations per hour, corresponding to rate accelerations of approximately 5 x10(5) over the templated, but otherwise uncatalyzed, background reaction rate. Three characterized ribozymes catalyzed the formation of 3'-5'-phosphodiester bonds and were highly specific for activation by AMP at the ligation site. CONCLUSIONS: The existence of a new class of ligase ribozymes is consistent with the hypothesis that the unusual mechanism of the biological ligases resulted from a conservation of mechanism during an evolutionary replacement of a primordial ribozyme ligase by a more modern protein enzyme. The newly isolated ligase ribozymes may also provide a starting point for the isolation of ribozymes that catalyze the polymerization of AMP-activated oligonucleotides or mononucleotides, which might have been the prebiotic analogs of nucleoside triphosphates.

  1. Antibacterial Activity of Some Plant Extracts Against Extended- Spectrum Beta-Lactamase Producing Escherichia coli Isolates

    PubMed Central

    Saeidi, Saeide; Amini Boroujeni, Negar; Ahmadi, Hassan; Hassanshahian, Mehdi

    2015-01-01

    Background: The extended-spectrum beta-lactamase (ESBL) -producing Escherichia coli isolates make many serious infections, especially urinary tract infections. Objectives: The purpose of this study was to determine the antibacterial activities of some natural plant extracts against ESBL-producing E. coli isolates, which harbor the TEM gene in urine samples of the patients who have urinary tract infections. Materials and Methods: Evaluation has to be exactly determined for both methods of disk diffusion test and polymerase chain reaction (PCR), separately. We evaluated 120 strains of E. coli isolates from the urine culture of the patients in Boo-Ali Hospital (Zahedan, south-eastern Iran) who were suffering from urinary tract infections. The ESBL-producing E. coli isolates were evaluated by disk diffusion test and PCR through TEM gene detection. The minimal inhibitory concentration (MIC) of commonly used antibiotics including ceftazidime, ceftriaxon, amikacin, gentamicin and ciprofloxacin along with the MIC of the alcoholic extract of different natural plants including Myrtus communis L (Myrtaceae), Amaranthus retraflexus (Amaranthaceae), Cyminum cuminum L (Apiaceae), Marrubium vulgare (Laminaceae) and Peganum. harmala (Zygrophyllaceae) against the ESBL-producing E. coli isolates, which harbor the TEM genes, were determined using the microdulition method. Results: Results of this study showed that in disk diffusion method, 80 samples of E. coli produced ESBLs. In PCR method, the TEM gene distribution in the isolated ESBL-producing organisms was 50 (41.6%). Amikacin was the most effective anti-bacterial agent and ciprofloxacin was the least effective against E. coli isolates. All the natural plant extracts mentioned above, especially P. harmala, were effective against the selected isolates of ESBL-producing E. coli. The most frequent ESBL rate producing E. coli isolates (32 out of 50) had MIC of 2.5 mg/mL in ethanol extract of P. harmala. Conclusions: The alcoholic

  2. Proteinase and phospholipase activities and development at different temperatures of yeasts isolated from bovine milk.

    PubMed

    Melville, Priscilla A; Benites, Nilson R; Ruz-Peres, Monica; Yokoya, Eugenio

    2011-11-01

    The presence of yeasts in milk may cause physical and chemical changes limiting the durability and compromising the quality of the product. Moreover, milk and dairy products contaminated by yeasts may be a potential means of transmission of these microorganisms to man and animals causing several kinds of infections. This study aimed to determine whether different species of yeasts isolated from bovine raw milk had the ability to develop at 37°C and/or under refrigeration temperature. Proteinase and phospholipase activities resulting from these yeasts were also monitored at different temperatures. Five genera of yeasts (Aureobasidium sp., Candida spp., Geotrichum spp., Trichosporon spp. and Rhodotorula spp.) isolated from bovine raw milk samples were evaluated. All strains showed one or a combination of characteristics: growth at 37°C (99·09% of the strains), psychrotrophic behaviour (50·9%), proteinase production (16·81% of the strains at 37°C and 4·09% under refrigeration) and phospholipase production (36·36% of the isolates at 37°C and 10·9% under refrigeration), and all these factors may compromise the quality of the product. Proteinase production was similar for strains incubated at 37°C (16·81% of the isolates) and room temperature (17·27%) but there was less amount of phospholipase-producing strains at room temperature (15·45% of the isolates were positive) when compared with incubation at 37°C (36·36%). Enzymes production at 37°C by yeasts isolated from milk confirmed their pathogenic potential. The refrigeration temperature was found to be most efficient to inhibit enzymes production and consequently ensure better quality of milk. The viability of yeasts and the activity of their enzymes at different temperatures are worrying because this can compromise the quality of dairy products at all stages of production and/or storage, and represent a risk to the consumer.

  3. In vitro activity of paldimycin (U-70138F) against gram-positive bacteria isolated from patients with cancer.

    PubMed Central

    Rolston, K V; LeBlanc, B; Ho, D H; Bodey, G P

    1987-01-01

    The in vitro activity of paldimycin, a novel antimicrobial agent, was compared with that of vancomycin against 306 gram-positive isolates (representing 12 bacterial species) obtained from patients with cancer. Paldimycin had lower MICs for 90% of isolates than vancomycin did against most isolates tested. Its activity, however, was medium and pH dependent, being greatest in Nutrient broth at a pH of 6.8. PMID:3606069

  4. Determination of the antibacterial activity of crude extracts and compounds isolated from Hortia oreadica (Rutaceae) against oral pathogens.

    PubMed

    Severino, Vanessa Gisele Pasqualotto; da Silva, Maria Fátima das Graças Fernandes; Lucarini, Rodrigo; Montanari, Lilian Bueno; Cunha, Wilson Roberto; Vinholis, Adriana Helena Chicharo; Martins, Carlos Henrique Gomes

    2009-07-01

    Extracts from Hortia oreadica afforded four dihydrocinnamic acid derivatives, isolated from the n-hexane extract, as well as limonoid guyanin and the furoquinoline alkaloid dictamnine, both isolated from the dichloromethane extract. The extracts and the isolated compounds were tested against some oral pathogens, so as to investigate their antibacterial activity. The results showed that the n-hexane extract and the compound dictamnine are the most active against the selected microorganisms.

  5. Issues concerning the application of seismic base isolation in the DOE

    SciTech Connect

    Sommer, S.C.; Trummer, D.J.

    1994-02-01

    Since the early 1970`s, the United States Department of Energy (DOE) has been engaged in a program to mitigate the effects of earthquakes on its facilities. Traditional means within the DOE or designing or retrofitting structures to withstand earthquakes include strengthening and anchoring. A nontraditional and in increasingly popular concept for lessening the effects of earthquakes on structures is seismic base isolation. Because base isolation is emerging as a promising technology for mitigating seismic effects, is potential role in the DOE must be evaluated. In order to use the technology within the DOE, there are technical and implementation issues that need to be carefully studied. By addressing these issues, base isolation can become a viable design option for mitigating the effects of earthquakes on DOE facilities. This overview paper discusses the potential applications of seismic base isolation in the DOE and the necessary steps for implementing the technology in the DOE.

  6. Flight performance of the International Space Station active rack isolation system

    NASA Astrophysics Data System (ADS)

    Bushnell, Glenn S.; Fialho, Ian J.; Allen, James L.; Quraishi, Naveed

    2003-10-01

    Space flight experiment test results of a Space Station Active Rack Isolation System (ARIS) are presented. The purpose of ARIS is to isolate microgravity sensitive science experiments mounted in Space Station racks from structural vibrations present on the large Space Station orbital structure. The ARIS is shown to solve the very difficult and challenging low frequency isolation problem by providing over an order of magnitude reduction in the acceleration at 0.1 Hz. The Station displacement response to crew motion is discussed along with the control method that ARIS employs to maintain microgravity performance while limiting the motion between the Station and the isolated rack. The dramatic difference between the Station acceleration levels during crew awake and sleep periods are presented. Some microgravity experiments are sensitive to angular acceleration, so both the translational and angular accelerations of the isolated rack are presented. The performance at frequencies up to 300 Hz was measured by exciting the Station structure with a proof-mass shaker and a hammer and these results, and the impacts from payload fans are presented. ARIS has been in operation for two years and three Zeolite Crystal Growth Experiments have been supported.

  7. Immunomodulatory potencies of isolated compounds from Crataegus azarolus through their antioxidant activities.

    PubMed

    Mustapha, Nadia; Mokdad-Bzéouich, Imèn; Sassi, Aicha; Abed, Besma; Ghedira, Kamel; Hennebelle, Thierry; Chekir-Ghedira, Leila

    2016-06-01

    The search of natural immunomodulatory agents has become an area of great interest in order to reduce damage to the human body. In this study, the immunomodulatory potential of Crataegus azarolus and its isolated hyperoside on mouse lymphocytes and macrophages in vitro was assessed. The effect of C. azarolus natural compounds on splenocytes proliferation, natural killer (NK) and cytotoxic T lymphocytes (CTL) activities, and on macrophage-mediated cytotoxicity were assessed by MTT test. Phagocytic activity and inhibition of nitric oxide (NO) release by macrophages were also evaluated. The antioxidant capacity of these products was evaluated by determining their cellular antioxidant activity (CAA) in splenocytes and macrophages. Depending on the concentrations, both ethyl acetate (EA) extract and hyperoside (Hyp) from C. azarolus affect macrophage functions by modulating their lysosomal enzyme activity and nitric oxide release. Whereas, the above-mentioned products significantly promote LPS and lectin-stimulated splenocyte proliferation, implying a potential activation of lymphocytes B and T enhancing humoral and cellular immune responses. Moreover, EA extract and Hyp could enhance the activity of NK and T lymphocytes cells, as well as the macrophages-mediated cytotoxicity against B16F10 cells. The anti-inflammatory activity was concomitant with the cellular antioxidant effect of the tested compounds against macrophages and splenocytes. Collectively, C. azarolus and its isolated hyperoside exhibited an immunomodulatory effect through their antioxidant activity. These findings suggest that C. azarolus should be explored as a novel potential immunomodulatory agent for the treatment of inflammatory diseases.

  8. Chemical characteristic and anticoagulant activity of the sulfated polysaccharide isolated from Monostroma latissimum (Chlorophyta).

    PubMed

    Mao, Wenjun; Li, Hongyan; Li, Yi; Zhang, Huijuan; Qi, Xiaohui; Sun, Haihong; Chen, Yin; Guo, Shoudong

    2009-01-01

    A polysaccharide was isolated from marine green algae Monostroma latissimum, and its chemical characteristic and anticoagulant activity were investigated. The results demonstrated that the polysaccharide was high rhamnose-containing sulfated polysaccharide, and was mainly composed of 1,2-linked l-rhamnose residues with sulfate groups substituted at positions C-3 and/or C-4. The sulfated polysaccharide exhibited high anticoagulant activities by assays of the activated partial thromboplastin time (APTT) and thrombin time (TT). The anticoagulant property of the sulfated polysaccharide was mainly attributed to powerful potentiation thrombin by heparin cofactor II.

  9. The polyacetylene falcarindiol with COX-1 activity isolated from Aegopodium podagraria L.

    PubMed

    Prior, Rikke M; Lundgaard, Nanna H; Light, Marnie E; Stafford, Gary I; van Staden, Johannes; Jäger, Anna K

    2007-08-15

    Extracts of Aegopodium podagraria L. were screened in vitro for cyclooxygenase-1 (COX-1) inhibitory activity. The isolation of the active compound falcarindiol was achieved by bioassay-guided fractionation. The identification of the active compound was confirmed by (1)H NMR and (13)C NMR. The IC(50)-value of falcarindiol was 0.3 microM in the COX-1 assay. A quantitative determination of the seasonal variation in the content of falcarindiol in different plant parts was carried out by HPLC analysis. The flowers from Aegopodium podagraria collected in June 2006 had the highest concentration of falcarindiol (88 mg/g plant material).

  10. Anti-trypanosomal activity of pentacyclic triterpenes isolated from Austroplenckia populnea (Celastraceae).

    PubMed

    Duarte, Lucienir Pains; Vieira Filho, Sidney Augusto; Silva, Grácia Divina de Fátima; de Sousa, José Rego; Pinto, Artur da Silveira

    2002-01-01

    Four pentacyclic triterpenes isolated from Austroplenckia populnea and four compounds of known anti T. cruzi or anti-malarial activity were tested. Of those triterpenes tested 20alpha-hydroxy-tingenone showed high activity, epikatonic acid was less active, while populnilic and populninic acids were inactive against the trypanosome of the subgenus Schizotrypanum tested. Benzonidazole, nifurtimox, ketoconazole and primaquine presented a remarkable dose-dependent inhibitory effect reaching practically to a total growth inhibition of the parasite at the end of incubation time. The trypanosome tested appear to be a suitable model for preliminary screen for anti T. (S.) cruzi compounds.

  11. A rapid method for detecting extracellular proteinase activity in Cryptococcus neoformans and a survey of 63 isolates.

    PubMed

    Ruma-Haynes, P; Brownlee, A G; Sorrell, T C

    2000-08-01

    A rapid method to detect extracellular proteolytic activity around colonies of Cryptococcus neoformans was developed with tannic acid used to complex with residual protein in a solid medium. A survey was conducted with 32 isolates of C. neoformans var. gattii and 31 isolates of C. neoformans var. neoformans which were cultured on medium containing gelatin as the sole nitrogen source. The annulus of clearing around fungal colonies was > 1.2 mm in 24 (77%) isolates of C. neoformans var. neoformans compared with only 7 (22%) isolates of C. neoformans var. gattii. There was no difference in proteolytic activity between environmental and human clinical isolates of C. neoformans. However, there was a difference between the size of the annulus around animal isolates of C. neoformans var. neoformans and isolates of the same variety from other sources. The annuli around the 14 animal isolates were all >1.2 mm, while 7 (70%) of 10 human clinical isolates and only 3 (43%) of 7 environmental isolates were scored in the high proteinase range. A difference between the genetic types (as characterised by RAPD typing) of C. neoformans var. gattii was also evident with 17 (77%) of 22 VG-I isolates having a small annulus compared with only 1 (17%) of 6 VG-II and VG-III isolates with annuli of similar size. Relatively low proteinase production by C. neoformans var. gattii may reduce local and systemic spread of infection in mammalian hosts.

  12. Intravenous immunoglobulin enhances the killing activity and autophagy of neutrophils isolated from immunocompromised patients against multidrug-resistant bacteria.

    PubMed

    Matsuo, Hidemasa; Itoh, Hiroshi; Kitamura, Naoko; Kamikubo, Yasuhiko; Higuchi, Takeshi; Shiga, Shuichi; Ichiyama, Satoshi; Kondo, Tadakazu; Takaori-Kondo, Akifumi; Adachi, Souichi

    2015-08-14

    Intravenous immunoglobulin (IVIG) is periodically administered to immunocompromised patients together with antimicrobial agents. The evidence that supports the effectiveness of IVIG is mostly based on data from randomized clinical trials; the underlying mechanisms are poorly understood. A recent study revealed that killing of multidrug-resistant bacteria and drug-sensitive strains by neutrophils isolated from healthy donors is enhanced by an IVIG preparation. However, the effectiveness of IVIG in immunocompromised patients remains unclear. The present study found that IVIG increased both killing activity and O2(-) release by neutrophils isolated from six patients receiving immune-suppressive drugs after hematopoietic stem cell transplantation (HSCT); these neutrophils killed both multidrug-resistant extended-spectrum β-lactamase-producing Escherichia coli (E. coli) and multidrug-resistant Pseudomonas aeruginosa (P. aeruginosa). Moreover, IVIG increased the autophagy of the neutrophils, which is known to play an important role in innate immunity. These results suggest that IVIG promotes both the killing activity and autophagy of neutrophils isolated from immunocompromised patients against multidrug-resistant bacteria.

  13. Antifungal Activity of Brazilian Propolis Microparticles against Yeasts Isolated from Vulvovaginal Candidiasis

    PubMed Central

    Dota, Kelen Fátima Dalben; Consolaro, Marcia Edilaine Lopes; Svidzinski, Terezinha Inez Estivalet; Bruschi, Marcos Luciano

    2011-01-01

    Propolis, a resinous compound produced by Apis mellifera L. bees, is known to possess a variety of biological activities and is applied in the therapy of various infectious diseases. The aim of this study was to evaluate the in vitro antifungal activity of propolis ethanol extract (PE) and propolis microparticles (PMs) obtained from a sample of Brazilian propolis against clinical yeast isolates of importance in the vulvovaginal candidiasis (VVC). PE was used to prepare the microparticles. Yeast isolates (n = 89), obtained from vaginal exudates of patients with VVC, were exposed to the PE and the PMs. Moreover, the main antifungal drugs used in the treatment of VVC (Fluconazole, Voriconazole, Itraconazole, Ketoconazole, Miconazole and Amphotericin B) were also tested. Minimum inhibitory concentration (MIC) was determined according to the standard broth microdilution method. Some Candida albicans isolates showed resistance or dose-dependent susceptibility for the azolic drugs and Amphotericin B. Non-C. albicans isolates showed more resistance and dose-dependent susceptibility for the azolic drugs than C. albicans. However, all of them were sensitive or dose-dependent susceptible for Amphotericin B. All yeasts were inhibited by PE and PMs, with small variation, independent of the species of yeast. The overall results provided important information for the potential application of PMs in the therapy of VVC and the possible prevention of the occurrence of new symptomatic episodes. PMID:21607012

  14. Anti-plasmodial activity of some Zulu medicinal plants and of some triterpenes isolated from them.

    PubMed

    Simelane, Mthokozisi B C; Shonhai, Addmore; Shode, Francis O; Smith, Peter; Singh, Mogie; Opoku, Andy R

    2013-10-08

    Mimusops caffra E. Mey. ex A.DC and Mimusops obtusifolia Lam (both members of the Sapotaceae family), and Hypoxis colchicifolia Bak (family Hypoxidaceae) are used by traditional healers in Zululand to manage malaria. Anti-plasmodial investigation of the crude extracts and some triterpenes isolated from the plants showed activity against a chloroquine sensitive (CQS) strain of Plasmodium falciparum (D10). Among the crude extracts the leaves of M. caffra exhibited the highest activity, with an IC₅₀ of 2.14 μg/mL. The pentacyclic tritepenoid ursolic acid (1), isolated from the leaves of M. caffra was the most active compound (IC₅₀ 6.8 μg/mL) as compared to taraxerol (2) and sawamilletin (3) isolated from the stem bark of M. obtusifolia (IC₅₀ > 100). Chemical modification of the ursolic acid (1) to 3β-acetylursolic acid (4) greatly enhanced its anti-plasmodial activity. Compound 4 reduced parasitaemia against Plasmodium berghei by 94.01% in in vivo studies in mice. The cytotoxicity of 3β-acetylursolic acid (IC₅₀) to two human cell lines (HEK293 and HepG2) was 366.00 μg/mL and 566.09 μg/mL, respectively. The results validate the use of these plants in folk medicine.

  15. Antimicrobial and antioxidant activities of Enterococcus species isolated from meat and dairy products.

    PubMed

    Pieniz, S; Andreazza, R; Okeke, B C; Camargo, F A O; Brandelli, A

    2015-11-10

    AbstractLactic acid bacteria (LAB) have an important role in a great variety of fermented foods. In addition to their contribution to sensory characteristics, they enhance food preservation and can be used as probiotics. In this study, the antimicrobial and antioxidant activities of culture supernatants and cell free extracts of 16 LAB isolated from meat and dairy products were investigated. The bacterial were identified by 16S rRNA sequencing. GenBank BLAST analysis revealed that all the isolates belong to Enterococcus faeciumspecies. Antimicrobial activity against the indicator microorganism (Listeria monocytogenes) was observed at 11 culture supernatants and 4 cell free extracts. The sensibility of culture supernatant was evaluated by proteinase K and trypsin and it was observed that activity of antimicrobial substance was completely lost after the treatment. All of the isolates showed antioxidant activity as determined by the Thiobarbituric Acid Reactive Substances (TBARS) method with both types of extracts. When the antioxidant capacity was investigated using ABTS•+ method (2,2 azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH method (2,2-diphenyl-1-picrylhydrazyl) it was observed that only culture supernatants showed antioxidant capacity. These bacteria could particularly help to reduce or inhibit pathogenic microorganisms as well as oxidative spoilage in foods and feed.

  16. Antimicrobial and antioxidant activities of Enterococcus species isolated from meat and dairy products.

    PubMed

    Pieniz, S; Andreazza, R; Okeke, B C; Camargo, F A O; Brandelli, A

    2015-11-01

    Lactic acid bacteria (LAB) have an important role in a great variety of fermented foods. In addition to their contribution to sensory characteristics, they enhance food preservation and can be used as probiotics. In this study, the antimicrobial and antioxidant activities of culture supernatants and cell free extracts of 16 LAB isolated from meat and dairy products were investigated. The bacterial were identified by 16S rRNA sequencing. GenBank BLAST analysis revealed that all the isolates belong to Enterococcus faecium species. Antimicrobial activity against the indicator microorganism (Listeria monocytogenes) was observed at 11 culture supernatants and 4 cell free extracts. The sensibility of culture supernatant was evaluated by proteinase K and trypsin and it was observed that activity of antimicrobial substance was completely lost after the treatment. All of the isolates showed antioxidant activity as determined by the Thiobarbituric Acid Reactive Substances (TBARS) method with both types of extracts. When the antioxidant capacity was investigated using ABTS•+ method (2,2 azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH method (2,2-diphenyl-1-picrylhydrazyl) it was observed that only culture supernatants showed antioxidant capacity. These bacteria could particularly help to reduce or inhibit pathogenic microorganisms as well as oxidative spoilage in foods and feed.

  17. In vitro antimicrobial activity of five essential oils on multidrug resistant Gram-negative clinical isolates

    PubMed Central

    Sakkas, Hercules; Gousia, Panagiota; Economou, Vangelis; Sakkas, Vassilios; Petsios, Stefanos; Papadopoulou, Chrissanthy

    2016-01-01

    Aim/Background: The emergence of drug-resistant pathogens has drawn attention on medicinal plants for potential antimicrobial properties. The objective of the present study was the investigation of the antimicrobial activity of five plant essential oils on multidrug resistant Gram-negative bacteria. Materials and Methods: Basil, chamomile blue, origanum, thyme, and tea tree oil were tested against clinical isolates of Acinetobacter baumannii (n = 6), Escherichia coli (n = 4), Klebsiella pneumoniae (n = 7), and Pseudomonas aeruginosa (n = 5) using the broth macrodilution method. Results: The tested essential oils produced variable antibacterial effect, while Chamomile blue oil demonstrated no antibacterial activity. Origanum, Thyme, and Basil oils were ineffective on P. aeruginosa isolates. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values ranged from 0.12% to 1.50% (v/v) for tea tree oil, 0.25-4% (v/v) for origanum and thyme oil, 0.50% to >4% for basil oil and >4% for chamomile blue oil. Compared to literature data on reference strains, the reported MIC values were different by 2SD, denoting less successful antimicrobial activity against multidrug resistant isolates. Conclusions: The antimicrobial activities of the essential oils are influenced by the strain origin (wild, reference, drug sensitive, or resistant) and it should be taken into consideration whenever investigating the plants’ potential for developing new antimicrobials. PMID:27366345

  18. Cytotoxic and antibacterial activities of endophytic fungi isolated from plants at the National Park, Pahang, Malaysia

    PubMed Central

    2009-01-01

    Background Endophytes, microorganisms which reside in plant tissues, have potential in producing novel metabolites for exploitation in medicine. Cytotoxic and antibacterial activities of a total of 300 endophytic fungi were investigated. Methods Endophytic fungi were isolated from various parts of 43 plants from the National Park Pahang, Malaysia. Extracts from solid state culture were tested for cytotoxicity against a number of cancer cell lines using the MTT assay. Antibacterial activity was determined using the disc diffusion method. Results A total of 300 endophytes were isolated from various parts of plants from the National Park, Pahang. 3.3% of extracts showed potent (IC50 < 0.01 μg/ml) cytotoxic activity against the murine leukemic P388 cell line and 1.7% against a human chronic myeloid leukemic cell line K562. Sporothrix sp. (KK29FL1) isolated from Costus speciosus showed strong cytotoxicity against colorectal carcinoma (HCT116) and human breast adenocarcinoma (MCF7) cell lines with IC50 values of 0.05 μg/ml and 0.02 μg/ml, respectively. Antibacterial activity was demonstrated for 8% of the extracts. Conclusion Results indicate the potential for production of bioactive agents from endophytes of the tropical rainforest flora. PMID:19930582

  19. Isolation and characterization of fucoidans from five brown algae and evaluation of their antioxidant activity

    NASA Astrophysics Data System (ADS)

    Qu, Guiyan; Liu, Xu; Wang, Dongfeng; Yuan, Yi; Han, Lijun

    2014-10-01

    In this study, we evaluated the chemical property and antioxidant activity of fucoidans isolated from brown algae, Laminaria japonica (LJF), Lessonia nigrescens (LNF), Lessonia trabeculata (LTF), Ascophyllum mackaii (AMF), and Ecklonia maxima (EMF). LJF was less in sulfate content (14.16%) and more in galactose and mannose content (1.08 and 0.68) than the documented early. EMF contained 20%-30% of sulfate and fucose, 0.97 in molar ratio which was lower than that of sulfate to other four fucoidans (1.21-1.41). AMF (162 kDa) and EMF (150 kDa) were the first two largest in molecular weight, which were followed by LJP (126 kDa), LNF (113 kDa) and LTF (105 kDa). The fucoidans isolated these algae showed a wide range of antioxidant activity in vitro. It was found that the reducing power of the isolated fucoidans was positively correlated with their sulfate content and molecular weight. In addition, LNF and LTF at low concentrations exhibited high superoxide and hydroxyl radical scavenging activity. This demonstrated that low molecular weight fucoidans may perform a high antioxidant activity.

  20. Isolation of a novel deoxyribonuclease with antifungal activity from Asparagus officinalis seeds.

    PubMed

    Wang, H; Ng, T B

    2001-11-23

    A deoxyribonuclease distinct from the previously isolated asparagus ribosome-inactivating proteins, possessing a molecular weight of 30 kDa and requiring a pH of 7.5 for optimum hydrolytic activity toward herring sperm DNA, was isolated from Asparagus officinalis seeds. The isolation procedure involved extraction with saline, (NH(4))(2)SO(4) precipitation, ion-exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion-exchange chromatography on CM-Sepharose, and FPLC gel filtration on Superdex 75. The doxyribonuclease was unadsorbed onto DEAE-cellulose and Affi-gel blue gel and adsorbed onto CM-Sepharose. It exhibited the novel N-terminal sequence, GIEVIKIREL. The deoxyribonuclease was purified to a specific activity of 1584 units/mg. It was devoid of ribonuclease, protease, and HIV-1 reverse transcriptase-inhibitory activities. However, it inhibited cell-free translation in a rabbit reticulocyte lysate system with an IC(50) of 20 microM. It exhibited antifungal activity toward Botrytis cinerea but not toward Fusarium oxysporum and Mycosphaerella arachidicola.

  1. Complete genome sequence of Bacillus amyloliquefaciens B15 isolated from grape skin, a strain of strong inhibitory activity against fungi.

    PubMed

    Yan, Yinzhuo; Liu, Shiyu; Wang, Deliang; Xue, Jie; Guo, Danyang; Song, Xulei; Zhang, Fengjie; Huang, Shihai; Luan, Chunguang

    2016-06-20

    Bacillus amyloliquefaciens B15 is a Gram-positive, plant-associated bacterium which shows strong antifungal activity, isolated from grape skin in Xinjiang, China. The genome of B. amyloliquefaciens B15 comprises a 4,006,754bp long circular chromosome containing 3991 protein coding genes and 109 RNA genes. Based on genomic analysis, we identified the giant gene clusters, nonribosomal peptidesynthetases (NRPS), and polyketide synthases (PKS), responsible for the biosynthesis of numerous bioactive metabolites. In addition, several functionally related genes, such as TasA, were also been identified for the antagonistic effect on pathogenic fungi but has no effect on the growth of itself.

  2. On rate-dependent mechanical model for adaptive magnetorheological elastomer base isolator

    NASA Astrophysics Data System (ADS)

    Li, Yancheng; Li, Jianchun

    2017-04-01

    This paper presents research on the phenomenological model of an adaptive base isolator. The adaptive base isolator is made of field-dependent magnetorheological elastomer (MRE) which can alter its physical property under application of magnetic field. Experimental testing demonstrated that the developed MRE base isolator possesses an amazing ability to vary its stiffness under applied magnetic field. However, several challenges have been encountered when it comes modeling such novel device. For example, under a large deformation, the MRE base isolator exhibits a clear strain stiffening effect and this behavior escalates with the increasing of applied current. In addition, the MRE base isolator has also shown typical rate-dependent behavior. Following a review on mechanical models for viscos-elastic rubber devices, a novel rate-dependent model is proposed in this paper to capture the behavior of the new MRE base isolator. To develop a generalized model, the proposed model was evaluated using its performance under random displacement input and a seismic input. It shows that the proposed rate-dependent model can successfully describe the complex behavior of the device.

  3. Pseudonocardia hispaniensis sp. nov., a novel actinomycete isolated from industrial wastewater activated sludge.

    PubMed

    Cuesta, G; Soler, A; Alonso, J L; Ruvira, M A; Lucena, T; Arahal, D R; Goodfellow, M

    2013-01-01

    A novel actinomycete, designated PA3(T), was isolated from an oil refinery wastewater treatment plant, located in Palos de la Frontera, Huelva, Spain, and characterized taxonomically by using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate formed a distinct subclade in the Pseudonocardia tree together with Pseudonocardia asaccharolytica DSM 44247(T). The chemotaxonomic properties of the isolate, for example, the presence of MK-8 (H(4)) as the predominant menaquinone and iso-C(16:0) as the major fatty acid, are consistent with its classification in the genus Pseudonocardia. DNA:DNA pairing experiments between the isolate and the type strain of P. asaccharolytica DSM 44247(T) showed that they belonged to separate genomic species. The two strains were readily distinguished using a combination of phenotypic properties. Consequently, it is proposed that isolate PA3(T) represents a novel species for which the name Pseudonocardia hispaniensis sp. nov. is proposed. The type strain is PA3(T) (= CCM 8391(T) = CECT 8030(T)).

  4. Effects of culture medium compositions on antidiabetic activity and anticancer activity of marine endophitic bacteria isolated from sponge

    NASA Astrophysics Data System (ADS)

    Maryani, Faiza; Mulyani, Hani; Artanti, Nina; Udin, Linar Zalinar; Dewi, Rizna Triana; Hanafi, Muhammad; Murniasih, Tutik

    2017-01-01

    High diversity of Indonesia marine spesies and their ability in producing secondary metabolite that can be used as a drug candidate cause this fascinating topic need to explore. Most of marine organisms explored to discover drug is macroorganism whereas microorganism (such as Indonesia marine bacteria) is very limited. Therefore, in this report, antidiabetic and anticancer activity of Indonesia marine bacteria isolated from Sponges's extract have been studied. Bacteria strain 8.9 which are collection of Research Center for Oseanography, Indonesian Institute of Sciences were from Barrang Lompo Island, Makasar, Indonesia. Bacteria were cultured in different culture medium compositions (such as: different pH, source of glucose and water) for 48 hours on a shaker, then they were extracted with ethyl asetate. Extracts of bacteria were tested by DPPH method (antioxidant activity), alpha glucosidase inhibitory activity method (antidiabetic activity), and Alamar Blue assay (anticancer activity) at 200 ppm. According to result, extract of bacteria in pH 8.0 exhibited the greatest antioxidant (19.27% inhibition), antidiabetic (63.95% inhibition) and anticancer activity of T47D cell line (44.62% cell viability) compared to other extracts. However, effect of addition of sugar sources (such as: glucose, sucrose, and soluble starch) and effect of addition of water/sea water exhibited less influence on their bioactivities. In conclusion, Indonesia marine bacteria isolated from sponge have potential a source of bioactive compound in drug discovery field.

  5. Chronic social isolation reduces 5-HT neuronal activity via upregulated SK3 calcium-activated potassium channels

    PubMed Central

    Sargin, Derya; Oliver, David K; Lambe, Evelyn K

    2016-01-01

    The activity of serotonin (5-HT) neurons is critical for mood regulation. In a mouse model of chronic social isolation, a known risk factor for depressive illness, we show that 5-HT neurons in the dorsal raphe nucleus are less responsive to stimulation. Probing the responsible cellular mechanisms pinpoints a disturbance in the expression and function of small-conductance Ca2+-activated K+ (SK) channels and reveals an important role for both SK2 and SK3 channels in normal regulation of 5-HT neuronal excitability. Chronic social isolation renders 5-HT neurons insensitive to SK2 blockade, however inhibition of the upregulated SK3 channels restores normal excitability. In vivo, we demonstrate that inhibiting SK channels normalizes chronic social isolation-induced anxiety/depressive-like behaviors. Our experiments reveal a causal link for the first time between SK channel dysregulation and 5-HT neuron activity in a lifelong stress paradigm, suggesting these channels as targets for the development of novel therapies for mood disorders. DOI: http://dx.doi.org/10.7554/eLife.21416.001 PMID:27874831

  6. Isolation of free-living dinitrogen-fixing bacteria and their activity in compost containing de-inking paper sludge.

    PubMed

    Beauchamp, Chantal J; Lévesque, Gabriel; Prévost, Danielle; Chalifour, François-P

    2006-05-01

    Knowledge of the microbiology of dinitrogen (N2)-fixing bacteria in compost rich in de-inking paper sludge (DPS) is limited. Dinitrogen (N2)-fixing bacteria from DPS composts were isolated and studied for their N2-fixing activity in vitro and in vivo. Two Gram-negative N2-fixing isolates were identified as Pseudomonas. At 20 degrees C, both isolates revealed that N2-fixing activity was higher than that of three arctic Pseudomonas strains. Their N2-fixing activity was found to occur between 18 and 25 degrees C, a pattern that was similar to the reference isolate Azotobacter ATCC 7486. Composts successfully showed N2-fixing activity after carbohydrate amendments both with and without inoculation of a N2-fixing isolate. These results suggest that DPS composts support N2-fixing bacteria and that N2-fixing activity is dependent on a usable carbohydrate source.

  7. Comparing brain activation associated with isolated upper and lower limb movement across corresponding joints.

    PubMed

    Luft, Andreas R; Smith, Gerald V; Forrester, Larry; Whitall, Jill; Macko, Richard F; Hauser, Till-Karsten; Goldberg, Andrew P; Hanley, Daniel F

    2002-10-01

    It was shown recently that functional activation across brain motor areas during locomotion and foot movements are similar but differ substantially from activation related to upper extremity movement (Miyai [2001]: Neuroimage 14:1186-1192). The activation pattern may be a function of the behavioral context of the movement rather than of its mechanical properties. We compare motor system activation patterns associated with isolated single-joint movement of corresponding joints in arm and leg carried out in equal frequency and range. Eleven healthy volunteers underwent BOLD-weighted fMRI while performing repetitive elbow or knee extension/flexion. To relate elbow and knee activation to the well-described patterns of finger movement, serial finger-to-thumb opposition was assessed in addition. After identifying task-related voxels using statistical parametric mapping, activation was measured in five regions of interest (ROI; primary motor [M1] and somatosensory cortex [S1], premotor cortex, supplementary motor area [SMA] divided into preSMA and SMA-proper, and cerebellum). Differences in the degree of activation across ROIs were found between elbow and knee movement. SMA-proper activation was prominent for knee, but almost absent for elbow movement (P < 0.05); finger movement produced small but constant SMA-proper activation. Ipsilateral M1 activation was detected during knee and finger movement, but was absent for the elbow task (P < 0.05). Knee movement showed less lateralization in M1 and S1 than other tasks (P < 0.05). The data demonstrate that central motor structures contribute differently to isolated elbow and knee movement. Activation during knee movement shows similarities to gait-related activation patterns.

  8. Large-scale isolation and cytotoxicity of extracellular vesicles derived from activated human natural killer cells

    PubMed Central

    Jong, Ambrose Y.; Wu, Chun-Hua; Li, Jingbo; Sun, Jianping; Fabbri, Muller; Wayne, Alan S.; Seeger, Robert C.

    2017-01-01

    ABSTRACT Extracellular vesicles (EVs) have been the focus of great interest, as they appear to be involved in numerous important cellular processes. They deliver bioactive macromolecules such as proteins, lipids, and nucleic acids, allowing intercellular communication in multicellular organisms. EVs are secreted by all cell types, including immune cells such as natural killer cells (NK), and they may play important roles in the immune system. Currently, a large-scale procedure to obtain functional NK EVs is lacking, limiting their use clinically. In this report, we present a simple, robust, and cost-effective method to isolate a large quantity of NK EVs. After propagating and activating NK cells ex vivo and then incubating them in exosome-free medium for 48 h, EVs were isolated using a polymer precipitation method. The isolated vesicles contain the tetraspanin CD63, an EV marker, and associated proteins (fibronectin), but are devoid of cytochrome C, a cytoplasmic marker. Nanoparticle tracking analysis showed a size distribution between 100 and 200 nm while transmission electron microscopy imaging displayed vesicles with an oval shape and comparable sizes, fulfilling the definition of EV. Importantly, isolated EV fractions were cytotoxic against cancer cells. Furthermore, our results demonstrate for the first time that isolated activated NK (aNK) cell EVs contain the cytotoxic proteins perforin, granulysin, and granzymes A and B, incorporated from the aNK cells. Activation of caspase -3, -7 and -9 was detected in cancer cells incubated with aNK EVs, and caspase inhibitors blocked aNK EV-induced cytotoxicity, suggesting that aNK EVs activate caspase pathways in target cells. The ability to isolate functional aNK EVs on a large scale may lead to new clinical applications. Abbreviations: NK: natural killer cells; activated NK (aNK) cells; EVs: extracellular vesicles; ALL: acute lymphoblastic leukaemia; aAPC: artificial antigen-presenting cell; TEM: transmission

  9. Activity Based Curriculum for Elementary Education. Additional Activities, K-6.

    ERIC Educational Resources Information Center

    Wichita Public Schools, KS.

    This elementary curriculum is a vehicle to provide manipulative activities that reinforce academic skills through meaningful, relevant, activity-based awareness of modern society. The twenty-six activity plans included in the curriculum place a major emphasis upon realistic or concrete experiences that deal with the manipulation and exploration of…

  10. Advances in antitumor polysaccharides from phellinus sensu lato: Production, isolation, structure, antitumor activity, and mechanisms.

    PubMed

    Yan, Jing-Kun; Pei, Juan-Juan; Ma, Hai-Le; Wang, Zhen-Bin; Liu, Yuan-Shuai

    2017-04-13

    Edible and medicinal fungi (mushrooms) are widely applied to functional foods and nutraceutical products because of their proven nutritive and medicinal properties. Phellinus sensu lato is a well-known medicinal mushroom that has long been used in preventing ailments, including gastroenteric dysfunction, diarrhea, hemorrhage, and cancers, in oriental countries, particularly in China, Japan, and Korea. Polysaccharides represent a major class of bioactive molecules in Phellinus s. l., which have notable antitumor, immunomodulatory, and medicinal properties. Polysaccharides that were isolated from fruiting bodies, cultured mycelia, and filtrates of Phellinus s. l. have not only activated different immune responses of the host organism but have also directly suppressed tumor growth and metastasis. Studies suggest that polysaccharides from Phellinus s. l. are promising alternative anticancer agents or synergizers for existing antitumor drugs. This review summarizes the recent development of polysaccharides from Phellinus s. l., including polysaccharide production, extraction and isolation methods, chemical structure, antitumor activities, and mechanisms of action.

  11. In Vitro Activity of Simeprevir against Hepatitis C Virus Genotype 1 Clinical Isolates and Its Correlation with NS3 Sequence and Site-Directed Mutants

    PubMed Central

    Fevery, Bart; Vijgen, Leen; Jacobs, Tom; De Meyer, Sandra; Lenz, Oliver

    2015-01-01

    Simeprevir (TMC435) is a once-daily, single-pill, oral hepatitis C virus (HCV) NS3 protease inhibitor approved for the treatment of chronic HCV infection. Phenotypic characterization of baseline isolates and isolates from HCV genotype 1-infected patients failing with a simeprevir-based regimen was performed using chimeric replicons carrying patient-derived NS3 protease sequences. Cutoff values differentiating between full susceptibility to simeprevir (≤2.0-fold reduction in simeprevir activity) and low-level versus high-level resistance (≥50-fold reduction in simeprevir activity) were determined. The median simeprevir fold change in the 50% effective concentration (FC) of pretreatment genotype 1a isolates, with and without Q80K, and genotype 1b isolates was 11, 0.9, and 0.4, respectively. Naturally occurring NS3 polymorphisms that reduced simeprevir activity, other than Q80K, were uncommon in the simeprevir studies and generally conferred low-level resistance in vitro. Although the proportion of patients with failure differed by HCV geno/subtype and/or presence of baseline Q80K, the level of simeprevir resistance observed at failure was similarly high irrespective of type of failure, HCV genotype 1 subtype, and presence or absence of baseline Q80K. At the end of the study, simeprevir activity against isolates that lost the emerging amino acid substitution returned to pretreatment values. Activity of simeprevir against clinical isolates and site-directed mutant replicons harboring the corresponding single or double amino acid substitutions correlated well, showing that simeprevir resistance can be attributed to these substitutions. In conclusion, pretreatment NS3 isolates were generally fully susceptible (FC, ≤2.0) or conferred low-level resistance to simeprevir in vitro (FC, >2.0 and <50). Treatment failure with a simeprevir-based regimen was associated with emergence of high-level-resistance variants (FC, ≥50). PMID:26392483

  12. Successful performance of a base-isolated hospital building during the 17 January 1994 northridge earthquake

    USGS Publications Warehouse

    Celebi, M.

    1996-01-01

    The purpose of this paper is to examine the response records and thereby the performance of the base-isolated University of Southern California (USC) hospital building during the Ms = 6-8 Northridge (California) earthquake of 17 January 1994. The data retrieved from the building is the first set of data from any base-isolated building that (a) was tested to acceleration levels at the free-field similar to the zero period acceleration (ZPA) level postulated in the seismic design criteria of the building and (b) exhibits levels of relative displacement excursions which puts the isolators into the nonlinear range. The variation of the fundamental frequency as a function of changing instantaneous stiffness of the isolators is identifiable. During the shaking, the isolators (a) performed well and, having attained up to 10% hysteretic damping, effectively dissipated the incoming energy of motions and (b) reduced the drift ratios of the superstructure of the building to a maximum of 10% of the allowable, which should explain the fact that there was no damage to the structure or its contents. The primary conclusion of this study is that this base-isolated building performed well during the Northridge earthquake of 17 January 1994 when only approximately 10% of the displacement capability of the isolators were utilized. Therefore, there is every reason to believe that the building will perform well during future earthquakes in the region.

  13. Seismic performance assessment of base-isolated safety-related nuclear structures

    USGS Publications Warehouse

    Huang, Y.-N.; Whittaker, A.S.; Luco, N.

    2010-01-01

    Seismic or base isolation is a proven technology for reducing the effects of earthquake shaking on buildings, bridges and infrastructure. The benefit of base isolation has been presented in terms of reduced accelerations and drifts on superstructure components but never quantified in terms of either a percentage reduction in seismic loss (or percentage increase in safety) or the probability of an unacceptable performance. Herein, we quantify the benefits of base isolation in terms of increased safety (or smaller loss) by comparing the safety of a sample conventional and base-isolated nuclear power plant (NPP) located in the Eastern U.S. Scenario- and time-based assessments are performed using a new methodology. Three base isolation systems are considered, namely, (1) Friction Pendulum??? bearings, (2) lead-rubber bearings and (3) low-damping rubber bearings together with linear viscous dampers. Unacceptable performance is defined by the failure of key secondary systems because these systems represent much of the investment in a new build power plant and ensure the safe operation of the plant. For the scenario-based assessments, the probability of unacceptable performance is computed for an earthquake with a magnitude of 5.3 at a distance 7.5 km from the plant. For the time-based assessments, the annual frequency of unacceptable performance is computed considering all potential earthquakes that may occur. For both assessments, the implementation of base isolation reduces the probability of unacceptable performance by approximately four orders of magnitude for the same NPP superstructure and secondary systems. The increase in NPP construction cost associated with the installation of seismic isolators can be offset by substantially reducing the required seismic strength of secondary components and systems and potentially eliminating the need to seismically qualify many secondary components and systems. ?? 2010 John Wiley & Sons, Ltd.

  14. Antimicrobial activity of bacteriocin-producing lactic acid bacteria isolated from cheeses and yogurts.

    PubMed

    Yang, En; Fan, Lihua; Jiang, Yueming; Doucette, Craig; Fillmore, Sherry

    2012-09-10

    The biopreservation of foods using bacteriocinogenic lactic acid bacteria (LAB) isolated directly from foods is an innovative approach. The objectives of this study were to isolate and identify bacteriocinogenic LAB from various cheeses and yogurts and evaluate their antimicrobial effects on selected spoilage and pathogenic microorganisms in vitro as well as on a food commodity.LAB were isolated using MRS and M17 media. The agar diffusion bioassay was used to screen for bacteriocin or bacteriocin-like substances (BLS) producing LAB using Lactobacillus sakei and Listeria innocua as indicator organisms. Out of 138 LAB isolates, 28 were found to inhibit these bacteria and were identified as strains of Enterococcus faecium, Streptococcus thermophilus, Lactobacillus casei and Lactobacillus sakei subsp. sakei using 16S rRNA gene sequencing. Eight isolates were tested for antimicrobial activity at 5°C and 20°C against L. innocua, Escherichia coli, Bacillus cereus, Pseudomonas fluorescens, Erwinia carotovora, and Leuconostoc mesenteroides subsp. mesenteroides using the agar diffusion bioassay, and also against Penicillium expansum, Botrytis cinerea and Monilinia frucitcola using the microdilution plate method. The effect of selected LAB strains on L. innocua inoculated onto fresh-cut onions was also investigated.Twenty percent of our isolates produced BLS inhibiting the growth of L. innocua and/or Lact. sakei. Organic acids and/or H2O2 produced by LAB and not the BLS had strong antimicrobial effects on all microorganisms tested with the exception of E. coli. Ent. faecium, Strep. thermophilus and Lact. casei effectively inhibited the growth of natural microflora and L. innocua inoculated onto fresh-cut onions. Bacteriocinogenic LAB present in cheeses and yogurts may have potential to be used as biopreservatives in foods.

  15. Antimicrobial activity of bacteriocin-producing lactic acid bacteria isolated from cheeses and yogurts

    PubMed Central

    2012-01-01

    The biopreservation of foods using bacteriocinogenic lactic acid bacteria (LAB) isolated directly from foods is an innovative approach. The objectives of this study were to isolate and identify bacteriocinogenic LAB from various cheeses and yogurts and evaluate their antimicrobial effects on selected spoilage and pathogenic microorganisms in vitro as well as on a food commodity. LAB were isolated using MRS and M17 media. The agar diffusion bioassay was used to screen for bacteriocin or bacteriocin-like substances (BLS) producing LAB using Lactobacillus sakei and Listeria innocua as indicator organisms. Out of 138 LAB isolates, 28 were found to inhibit these bacteria and were identified as strains of Enterococcus faecium, Streptococcus thermophilus, Lactobacillus casei and Lactobacillus sakei subsp. sakei using 16S rRNA gene sequencing. Eight isolates were tested for antimicrobial activity at 5°C and 20°C against L. innocua, Escherichia coli, Bacillus cereus, Pseudomonas fluorescens, Erwinia carotovora, and Leuconostoc mesenteroides subsp. mesenteroides using the agar diffusion bioassay, and also against Penicillium expansum, Botrytis cinerea and Monilinia frucitcola using the microdilution plate method. The effect of selected LAB strains on L. innocua inoculated onto fresh-cut onions was also investigated. Twenty percent of our isolates produced BLS inhibiting the growth of L. innocua and/or Lact. sakei. Organic acids and/or H2O2 produced by LAB and not the BLS had strong antimicrobial effects on all microorganisms tested with the exception of E. coli. Ent. faecium, Strep. thermophilus and Lact. casei effectively inhibited the growth of natural microflora and L. innocua inoculated onto fresh-cut onions. Bacteriocinogenic LAB present in cheeses and yogurts may have potential to be used as biopreservatives in foods. PMID:22963659

  16. Taxonomic Characterization, Evaluation of Toxigenicity, and Saccharification Capability of Aspergillus Section Flavi Isolates from Korean Traditional Wheat-Based Fermentation Starter Nuruk

    PubMed Central

    Bal, Jyotiranjan; Yun, Suk-Hyun; Chun, Jeesun; Kim, Beom-Tae

    2016-01-01

    The most economically important species used in a wide range of fermentation industries throughout Asia belong to Aspergillus section Flavi, which are morphologically and phylogenetically indistinguishable, with a few being toxigenic and therefore a major concern. They are frequently isolated from Korean fermentation starters, such as nuruk and meju. The growing popularity of traditional Korean alcoholic beverages has led to a demand for their quality enhancement, therefore requiring selection of efficient non-toxigenic strains to assist effective fermentation. This study was performed to classify the most efficient strains of Aspergillus section Flavi isolated from various types of traditional wheat nuruk, based on a polyphasic approach involving molecular and biochemical evaluation. A total of 69 strains were isolated based on colony morphology and identified as Aspergillus oryzae/flavus based on internal transcribed spacer and calmodulin gene sequencing. Interestingly, none were toxigenic based on PCR amplification of intergenic regions of the aflatoxin cluster genes norB-cypA and the absence of aflatoxin in the culture supernatants by thin-layer chromatography analysis. Saccharification capability of the isolates, assessed through α-amylase and glucoamylase activities, revealed that two isolates, TNA24 and TNA15, showed the highest levels of activity. Although the degrees of variation in α-amylase and glucoamylase activities among the isolates were higher, there were only slight differences in acid protease activity among the isolates with two, TNA28 and TNA36, showing the highest activities. Furthermore, statistical analyses showed that α-amylase activity was positively correlated with glucoamylase activity (p < 0.001), and therefore screening for either was sufficient to predict the saccharifying capacity of the Aspergillus strain. PMID:27790066

  17. Concepts for the design of a completely active helicopter isolation system using output vector feedback

    NASA Technical Reports Server (NTRS)

    Schulz, G.

    1977-01-01

    The theory of output vector feedback (a few measured quantities) is used to derive completely active oscillation isolation functions for helicopters. These feedback controller concepts are tested with various versions of the BO 105 helicopter and their performance is demonstrated. A compensation of the vibrational excitations from the rotor and harmonics of the number of blades are considered. There is also a fast and automatic trim function for maneuvers.

  18. Structure elucidation and antioxidant activity of (-)-isosilandrin isolated from Silybum marianum L.

    PubMed

    Samu, Zsuzsanna; Nyiredy, Szabolcs; Baitz-Gács, Eszter; Varga, Zsuzsa; Kurtán, Tibor; Dinya, Zoltán; Antus, Sándor

    2004-11-01

    A regioisomer of the known flavanolignan (-)-silandrin (3a), named (-)-isosilandrin (8a), was isolated from the fruits of a white-flowered variant of Silybum marianum L. populated in Hungary. Its structure was established both by spectroscopic methods and total synthesis, and its absolute configuration was determined by means of circular dichroism. This compound showed stronger inhibitory activity on the superoxide anion (O2*-) release by human polymorphonuclear leukocytes (PMNL) than (+)-silybin (1a,b).

  19. Mechanical behavior of a suite of elastomers used for seismic base isolation

    SciTech Connect

    Kulak, R.F.; Hughes, T.H.

    1995-07-01

    Several practical systems have been developed to protect structures and their contents from the potential devastating consequences of earthquakes. The use of seismic isolation has recently proven to be an effective means to mitigate earthquake damage. With seismic isolation, the structures are decoupled from the strong horizontal ground accelerations. The use of high damping elastomer, steel lamiriated seismic isolation bearings has been proven to be an effective method for seismic base isolation. This paper describes recent research conducted at Argonne National Laboratory to find the mechanical response characteristics of a suite of elastomers compounded for use in elastomeric seismic isolation bearings. The response characteristics were obtained by testing small coupons of each elastomer in a high precision dynamic testing machine. Specifically, the paper reports on tests performed to find the variations in stiffness and energy dissipation with strain level, loading rate, and cycle number. The paper also reports on the effects that strain level has on stiffness recovery.

  20. Antimicrobial Activity of Actinobacteria Isolated From the Guts of Subterranean Termites.

    PubMed

    Arango, R A; Carlson, C M; Currie, C R; McDonald, B R; Book, A J; Green, F; Lebow, N K; Raffa, K F

    2016-09-28

    Subterranean termites need to minimize potentially pathogenic and competitive fungi in their environment in order to maintain colony health. We examined the ability of Actinobacteria isolated from termite guts in suppressing microorganisms commonly encountered in a subterranean environment. Guts from two subterranean termite species, Reticulitermes flavipes (Kollar) and Reticulitermes tibialis Banks, were extracted and plated on selective chitin media. A total of 38 Actinobacteria isolates were selected for in vitro growth inhibition assays. Target microbes included three strains of Serratia marcescens Bizio, two mold fungi (Trichoderma sp. and Metarhizium sp.), a yeast fungus (Candida albicans (C.P. Robin) Berkhout), and four basidiomycete fungi (Gloeophyllum trabeum (Persoon) Murrill, Tyromyces palustris (Berkeley & M.A. Curtis) Murrill, Irpex lacteus (Fries) Fries, and Trametes versicolor (L.) Lloyd). Results showed both broad and narrow ranges of antimicrobial activity against the mold fungi, yeast fungus, and S. marcescens isolates by the Actinobacteria selected. This suggests that termite gut-associated Actinobacteria produce secondary antimicrobial compounds that may be important for pathogen inhibition in termites. Basidiomycete fungi were strongly inhibited by the selected Actinobacteria isolates, with G. trabeum and T. versicolor being most inhibited, followed by I. lacteus and T. palustris The degree of inhibition was correlated with shifts in pH caused by the Actinobacteria. Nearly all Actinobacteria isolates raised pH of the growth medium to basic levels (i.e. pH ∼8.0-9.5). We summarize antimicrobial activity of these termite gut-associated Actinobacteria and examine the implications of these pH shifts.

  1. Antimicrobial Activity of Actinobacteria Isolated From the Guts of Subterranean Termites.

    PubMed

    Arango, R A; Carlson, C M; Currie, C R; McDonald, B R; Book, A J; Green, F; Lebow, N K; Raffa, K F

    2016-12-01

    Subterranean termites need to minimize potentially pathogenic and competitive fungi in their environment in order to maintain colony health. We examined the ability of Actinobacteria isolated from termite guts in suppressing microorganisms commonly encountered in a subterranean environment. Guts from two subterranean termite species, Reticulitermes flavipes (Kollar) and Reticulitermes tibialis Banks, were extracted and plated on selective chitin media. A total of 38 Actinobacteria isolates were selected for in vitro growth inhibition assays. Target microbes included three strains of Serratia marcescens Bizio, two mold fungi (Trichoderma sp. and Metarhizium sp.), a yeast fungus (Candida albicans (C.P. Robin) Berkhout), and four basidiomycete fungi (Gloeophyllum trabeum (Persoon) Murrill, Tyromyces palustris (Berkeley & M.A. Curtis) Murrill, Irpex lacteus (Fries) Fries, and Trametes versicolor (L.) Lloyd). Results showed both broad and narrow ranges of antimicrobial activity against the mold fungi, yeast fungus, and S. marcescens isolates by the Actinobacteria selected. This suggests that termite gut-associated Actinobacteria produce secondary antimicrobial compounds that may be important for pathogen inhibition in termites. Basidiomycete fungi were strongly inhibited by the selected Actinobacteria isolates, with G. trabeum and T. versicolor being most inhibited, followed by I. lacteus and T. palustris The degree of inhibition was correlated with shifts in pH caused by the Actinobacteria. Nearly all Actinobacteria isolates raised pH of the growth medium to basic levels (i.e. pH ∼8.0-9.5). We summarize antimicrobial activity of these termite gut-associated Actinobacteria and examine the implications of these pH shifts.

  2. Antifungal Activity of Cinnamon Oil and Olive Oil against Candida Spp. Isolated from Blood Stream Infections

    PubMed Central

    Rohilla, Hina; Singh, Gajender; Punia, Parul

    2016-01-01

    Introduction Recently non-albicans Candida has emerged as a major cause of morbidity and mortality in blood stream infections. Some species of the Candida are becoming increasingly resistant to first line and second line antifungals such as echinocandins and fluconazole. In view of increasing global antifungal resistance, role of alternative and better antifungals like natural plant products need to be explored. Essential oils are known to exhibit antimicrobial activity against various fungi. Hence, we evaluated the efficacy of cinnamon oil and olive oil against Candida spp. Aim To evaluate the invitro antifungal activity of olive oil and cinnamon oil against blood stream Candida isolates. Materials and Methods The present prospective observational study was conducted in the Department of Microbiology at a tertiary care teaching hospital during one year June 2011-July 2012. Blood samples were collected from 1376 patients clinically suspected to have fungal septicaemia, out of which 100 (7.2%) Candida isolates obtained, were speciated by conventional methods. Antifungal susceptibility testing of all the isolates was done against fluconazole, voriconazole as per NCCL (M27-A2) and against olive oil and cinnamon oil by agar well diffusion method. Results Prevalence of Candidemia was 7.26%. C. albicans (85.3%) and C. parapsilosis (85.7%) were most sensitive to fluconazole followed by C. tropicalis (67.4%). All isolates were 100% sensitive to voriconazole. Both oils were found to be effective against nearly 50% of the Candida isolates. About 55.5% of fluconazole resistant C. krusei strains were sensitive to olive and cinnamon oil. Conclusion Fluconazole resistant non-albicans Candida has emerged as major cause of Candidemia. Cinnamon and olive oil show marked sensitivity against albicans and non-albicans spp. PMID:27656437

  3. Sulfur oxidation in rice field soil: activity, enumeration, isolation and characterization of thiosulfate-oxidizing bacteria.

    PubMed

    Stubner, S; Wind, T; Conrad, R

    1998-12-01

    In rice paddy fields the bulk soil is anoxic, but oxygenated zones occur in the surrounding of the rice roots to where oxygen is transported via the aerenchyma system of the rice plants. In the anaerobic soil compartments sulfate is consumed by sulfate-reducing bacteria. In the rhizosphere the reduced sulfur compounds can be reoxidized by sulfur-oxidizing bacteria. Measurements of the potential activity of thiosulfate-oxidizing bacteria in soil slurries derived from planted rice soil microcosms showed turnover rates of 2-6 mumol d-1 g-dw-1. Thiosulfate was oxidized to sulfate with tetrathionate as intermediate. Most probable number (MPN) enumeration with three aerobic media and one anaerobic nitrate-amended medium showed that thiosulfate-oxidizing bacteria were abundant in paddy soil and in rhizosphere soil at numbers of 10(5) to 10(6) per gram dry weight soil. Nine isolates of S-oxidizing bacteria were obtained from enrichment cultures or from the highest dilutions of the MPN series and were affiliated to four different phylogenetic groups. These isolates were characterized by physiological properties and by comparative 16S rDNA sequence analysis. Three isolates (TA1-AE1, TA1-A1 and TA12-21) were shown to be facultatively chemolithoautotrophic strains of Ancylobacter aquaticus. Three further isolates (Tv6-2b, Z2A-6A and Z4A-2A) were also facultatively chemolithoautotrophic and were affiliated with the Xanthobacter sp. group, probably representing new strains of X. flavus or X. tagetidis. Strain SZ-2111 was phylogenetically related to Bosea thiooxidans. However, the genus Bosea is described as obligately heterotrophic, whereas strain 5Z-2111 was able to grow autotrophically. The isolates 5Z-C1 and TBW3 were obligate chemolithoautotrophs and were closely affiliated with Thiobacillus thioparus. Our results showed that S-oxidizing bacteria were abundant and active in rice paddy soil and consisted of physiologically and phylogenetically diverse populations.

  4. In vitro activity of U-63196E, a new cephalosporin, against clinical bacterial isolates.

    PubMed Central

    Eliopoulos, G M; Gardella, A; DeGirolami, P; Moellering, R C

    1984-01-01

    The in vitro activity of U-63196E, a new cephalosporin, was compared with those of other extended-spectrum cephalosporins and penicillins against clinical bacterial isolates. Against Pseudomonas aeruginosa, the activity of U-63196E was comparable to those of cefoperazone and piperacillin, each of which inhibited 90% of strains at concentrations of less than or equal to 16 micrograms/ml. The new drug also demonstrated activity against a variety of other bacterial species, but it was generally less active than cefotaxime, moxalactam, and cefoperazone against members of the family Enterobacteriaceae and staphylococci. The presence of any 1 of 10 plasmid-mediated beta-lactamases in a series of otherwise isogenic laboratory strains of P. aeruginosa resulted in a significant reduction in the activity of U-63196E in comparison with its activity against the parent strain, which lacks these enzymes. Combinations of U-63196E with tobramycin demonstrated bacteriostatic synergism against 11 of 20 clinical isolates of P. aeruginosa. PMID:6610385

  5. Isolation and antioxidant activity of flavonoids from Holarrhena floribunda (G.don) leaves.

    PubMed

    Badmus, Jelili A; Ekpo, Okobi E; Rautenbach, Fanie; Marnewick, Jeanine L; Hussein, Ahmed A; Hiss, Donavon C

    2016-01-01

    Bioactive polyphenolics are ubiquitously present in plants and may play an important role in the prevention and management of certain human diseases. Three known flavonoids viz Kaemperol-3-O-rutinoside (1), quercetin-3-O-glucoside (2) and kaemperol-3-O-glucoside (3) and inseparable mixture (1:1) of quercetin-3-O-glucose/galactose (4) were isolated, and identified for the first time from Holarrhena floribunda. The antioxidant capacity using the ORAC, FRAP and TEAC assays and inhibition of lipid peroxidation were measured for isolated flavonoids. The result showed that compounds 2 and 4 showed significantly increased ORAC, TEAC, and FRAP activities with low pro-oxidant potential as well as improved lipid peroxidation inhibition levels when compared to compounds 1 and 3. The most active compounds were found to be flavonoids with a quercetin basic structure. These results imply that the isolated flavonoid glycosides are responsible for the antioxidant activity of the plant leaves and it forms the scientific basis for its traditional usage.

  6. Rhodotorula Mucilaginosa, a Quorum Quenching Yeast Exhibiting Lactonase Activity Isolated from a Tropical Shoreline

    PubMed Central

    Ghani, Norshazliza Ab; Sulaiman, Joanita; Ismail, Zahidah; Chan, Xin-Yue; Yin, Wai-Fong; Chan, Kok-Gan

    2014-01-01

    Two microbial isolates from a Malaysian shoreline were found to be capable of degrading N-acylhomoserine lactones. Both Matrix Assisted Laser Desorption Ionization-Time of Flight-Mass Spectrometry and 18S rDNA phylogenetic analyses confirmed that these isolates are Rhodotorula mucilaginosa. Quorum quenching activities were detected by a series of bioassays and rapid resolution liquid chromatography analysis. The isolates were able to degrade various quorum sensing molecules namely N-hexanoyl-L-homoserine lactone (C6-HSL), N-(3-oxo-hexanoyl)-L-homoserine lactone (3-oxo-C6-HSL) and N-(3-hydroxyhexanoyl)-L-homoserine lactone (3-hydroxy-C6-HSL). Using a relactonisation assay to verify the quorum quenching mechanism, it is confirmed that Rh. mucilaginosa degrades the quorum sensing molecules via lactonase activity. To the best of our knowledge, this is the first documentation of the fact that Rh. mucilaginosa has activity against a broad range of AHLs namely C6-HSL, 3-oxo-C6-HSL and 3-hydroxy-C6-HSL. PMID:24721765

  7. Rhodotorula mucilaginosa, a quorum quenching yeast exhibiting lactonase activity isolated from a tropical shoreline.

    PubMed

    Ghani, Norshazliza Ab; Sulaiman, Joanita; Ismail, Zahidah; Chan, Xin-Yue; Yin, Wai-Fong; Chan, Kok-Gan

    2014-04-09

    Two microbial isolates from a Malaysian shoreline were found to be capable of degrading N-acylhomoserine lactones. Both Matrix Assisted Laser Desorption Ionization-Time of Flight-Mass Spectrometry and 18S rDNA phylogenetic analyses confirmed that these isolates are Rhodotorula mucilaginosa. Quorum quenching activities were detected by a series of bioassays and rapid resolution liquid chromatography analysis. The isolates were able to degrade various quorum sensing molecules namely N-hexanoyl-L-homoserine lactone (C6-HSL), N-(3-oxo-hexanoyl)-L-homoserine lactone (3-oxo-C6-HSL) and N-(3-hydroxyhexanoyl)-L-homoserine lactone (3-hydroxy-C6-HSL). Using a relactonisation assay to verify the quorum quenching mechanism, it is confirmed that Rh. mucilaginosa degrades the quorum sensing molecules via lactonase activity. To the best of our knowledge, this is the first documentation of the fact that Rh. mucilaginosa has activity against a broad range of AHLs namely C6-HSL, 3-oxo-C6-HSL and 3-hydroxy-C6-HSL.

  8. Antiinflammatory and Analgesic Activities of Ethanol Extract and Isolated Compounds from Millettia pulchra.

    PubMed

    Huo, Xiaowei; Zhang, Leilei; Gao, Li; Guo, Yan; Zhang, Lijing; Li, Liyong; Si, Jianyong; Cao, Li

    2015-01-01

    The plant Millettia pulchra was commonly used in folk medicine for the management of inflammation. However, there was no scientific rationale for these effects and the mechanism of action remained incompletely understood. The present study was designed to investigate the antiinflammatory and analgesic activities of an ethanol extract of the stem of M. pulchra (EMP) in vivo, and to explore the antiinflammatory activity of compounds isolated from EMP in vitro. We found that EMP reduced xylene-induced ear edema and relieved both acetic acid-induced pain and pain in the hot plate test. Additionally, a significant decrease in nitric oxide (NO) production was observed in cells treated with the isolated compounds. Lanceolatin B, which showed the greatest inhibition of NO synthesis among the compounds tested, also reduced levels of interleukin-1 beta (IL-1β), IL-6, tumor necrosis factor-alpha (TNF-α), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), nuclear factor-kappa B (NF-κB), and phosphorylation inhibitory kappa B alpha (p-IκBα) in a dose-dependent manner. These findings provide convincing evidence that EMP and the individual isolated compounds possess significant antiinflammatory and analgesic activities.

  9. Evaluation of Mosquito Repellent Activity of Isolated Oleic Acid, Eicosyl Ester from Thalictrum javanicum

    PubMed Central

    Gurunathan, Abinaya; Senguttuvan, Jamuna; Paulsamy, S.

    2016-01-01

    To evaluate the traditional use, the mosquito repellent property of Thalictrum javanicum and to confirm the predicted larvicidal activity of the isolated compound, oleic acid, eicosyl ester from its aerial parts by PASS software, the present study was carried out using 4th instar stage larvae of the mosquitoes, Aedes aegypti (dengue vector) and Culex quinquefasciatus (filarial vector). Insecticidal susceptibility tests were conducted and the mortality rate was observed after 24 h exposure. The chitinase activity of isolated compound was assessed by using purified β-N-acetyl glucosaminidase (chitinase). Ecdysone 20-monooxygenase assay (radioimmuno assay) was made using the same larval stage of A. aegyptiand C. quinquefasciatus. The results were compared with the crude methanol extract of the whole plant. The isolated compound, oleic acid, eicosyl ester was found to be the most effective larvicide against A. aegypti (LC50/24 h -8.51 ppm) and C. quinquefasciatus (LC50/24 h - 12.5 ppm) than the crude methanol extract (LC50/24 h - 257.03 ppm and LC50/24 h - 281.83 ppm, respectively). The impact of oleic acid, eicosyl ester on reducing the activity of chitinase and ecdysone 20-monooxygenase was most prominent in both the target species, A. aegyptiand C. quinquefasciatus than the control. The results therefore suggest that the compound, oleic acid, eicosyl ester from Thalictrum javanicum may be considered as a potent source of mosquito larvicidal property. PMID:27168688

  10. Antimicrobial activity of Calotropis procera Ait. (Asclepiadaceae) and isolation of four flavonoid glycosides as the active constituents.

    PubMed

    Nenaah, Gomah

    2013-07-01

    Antimicrobial activity of solvent extracts and flavonoids of Calotropis procera growing wild in Saudi Arabia was evaluated using the agar well-diffusion method. A bioassay-guided fractionation of the crude flavonoid fraction (Cf3) of MeOH extract which showed the highest antimicrobial activity led to the isolation of four flavonoid glycosides as the bioactive constituents. Structure of compounds have been elucidated using physical and spectroscopic methods including (UV, IR, (1)H, (13)C-NMR, DEPT, 2D (1)H-(1)H COSY, HSQC, HMBC and NOESY). Compounds were found to be the 3-O-rutinosides of quercetin, kaempferol and isorhamnetin, besides the flavonoid 5-hydroxy-3,7-dimethoxyflavone-4'-O-β-glucopyranoside. Most of the isolated extracts showed antimicrobial activity against the test microorganisms, where the crude flavonoid fraction was the most active, diameter of inhibition zones ranged between 15.5 and 28.5 mm against the tested bacterial strains, while reached 30 mm against the fungal Candida albicans. The minimal inhibitory concentrations varied from 0.04 to 0.32 mg/ml against all of the tested microorganisms in case of the crude flavonoid fraction. Quercetin-3-O-rutinoside showed superior activity over the remainder flavonoids. The Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) were more susceptible than the Gram-negative (Pseudomonas aeruginosa and Salmonella enteritidis) and the yeast species were more susceptible than the filamentous fungi. The study recommend the use of such natural products as antimicrobial biorationals.

  11. Strong transcriptional activators isolated from viral DNA by the 'activator trap', a novel selection system in mammalian cells.

    PubMed

    Gstaiger, M; Schaffner, W

    1994-10-11

    Transcription factors often contain activation domains that interact with the basic transcription machinery. We have developed a functional screening strategy in mammalian cells to selectively isolate activation domains from a library of random DNA inserts. For this, sonicated DNA fragments are cloned next to the DNA binding domain of GAL4 factor in a plasmid that also contains the SV40 origin of replication. Pools of fusion protein clones are transfected into CV-1-5GT monkey cells containing an SV40 T antigen gene under the control of a promoter with GAL4 binding sites. Plasmids that express functional transactivating fusion proteins activate the T antigen gene, thus promoting selective amplification of the plasmid in the mammalian host cell line. Using this method, we were able to select strong enhancer-type activation domains from the immediate early regions of two herpesviruses, namely pseudorabies virus and bovine herpesvirus 1. In both cases, the activation domains selected were homologues of the ICP4 regulatory protein of herpes simplex virus. The activation domain from pseudorabies virus is four times stronger than the activation domain of herpes simplex virus protein VP16 (Vmw65), making it the strongest activation domain characterized so far. This activator trap method should be useful for precisely localizing activation domain(s) in known factors, or to identify mammalian transcriptional adaptors that do not bind DNA and which may escape conventional detection methods.

  12. Structural analysis and antioxidant activities of polysaccharide isolated from Jinqian mushroom.

    PubMed

    Liu, Yong; Du, Yi-Qun; Wang, Jun-Hui; Zha, Xue-Qiang; Zhang, Jian-Bo

    2014-03-01

    Jinqian mushroom is a precious edible mushroom with delicious taste and high nutritional value. In this paper, a polysaccharide fraction JQPs was isolated and purified from the fruiting body of Jinqian mushroom. The chemical structure, chain conformation and antioxidant activities of JQPs were investigated. The results indicated that JQPs was mainly composed of glucose with trace amounts of xylose. The backbone of JQPs consisted of β-(1 → 3)-D-glucan with β-(1 → 6)-glucosyl side chain. The chain conformation analysis showed that JQPs was a triple helical polysaccharide. The antioxidant activity tests in vitro revealed that JQPs exhibited high DPPH radical and ABTS radical scavenging activities, moderate superoxide radical and hydroxyl radical scavenging activities, low reducing power and Fe(2+) chelating activities. The results suggested that JQPs could be used as a potential natural antioxidant.

  13. Biocontrol Activity of Bacillus subtilis Isolated from Agaricus bisporus Mushroom Compost Against Pathogenic Fungi.

    PubMed

    Liu, Can; Sheng, Jiping; Chen, Lin; Zheng, Yanyan; Lee, David Yue Wei; Yang, Yang; Xu, Mingshuang; Shen, Lin

    2015-07-08

    Bacillus subtilis strain B154, isolated from Agaricus bisporus mushroom compost infected by red bread mold, exhibited antagonistic activities against Neurospora sitophila. Antifungal activity against phytopathogenic fungi was also observed. The maximum antifungal activity was reached during the stationary phase. This antifungal activity was stable over a wide pH and temperature range and was not affected by proteases. Assay of antifungal activity in vitro indicated that a purified antifungal substance could strongly inhibit mycelia growth and spore germination of N. sitophila. In addition, treatment with strain B154 in A. bisporus mushroom compost infected with N. sitophila significantly increased the yield of bisporus mushrooms. Ultraviolet scan spectroscopy, tricine sodium dodecyl sulfate-polyacrylamide gel electrophoresis, matrix-associated laser desorption ionization time-of-flight mass spectrometry, and electrospray ionization tandem mass spectrometry analyses revealed a molecular weight consistent with 1498.7633 Da. The antifungal compound might belong to a new type of lipopeptide fengycin.

  14. Isolation and characterization of a Saccharomyces cerevisiae mutant with impaired glutamate synthase activity.

    PubMed

    Folch, J L; Antaramián, A; Rodríguez, L; Bravo, A; Brunner, A; González, A

    1989-12-01

    A mutant of Saccharomyces cerevisiae that lacks glutamate synthase (GOGAT) activity has been isolated. This mutant was obtained after chemical mutagenesis of a NADP-glutamate dehydrogenase-less mutant strain. The gdh gus mutant is a glutamate auxotroph. The genetic analysis of the gus mutant showed that the GOGAT-less phenotype is due to the presence of two loosely linked mutations. Evidence is presented which suggests the possibility that S. cerevisiae has two GOGAT activities, designated GOGAT A and GOGAT B. These activities can be distinguished by their pH optima and by their regulation by glutamate. Furthermore, one of the mutations responsible for the GOGAT-less phenotype affected GOGAT A activity, while the other mutation affected GOGAT B activity.

  15. Isolation and characterization of a Saccharomyces cerevisiae mutant with impaired glutamate synthase activity.

    PubMed Central

    Folch, J L; Antaramián, A; Rodríguez, L; Bravo, A; Brunner, A; González, A

    1989-01-01

    A mutant of Saccharomyces cerevisiae that lacks glutamate synthase (GOGAT) activity has been isolated. This mutant was obtained after chemical mutagenesis of a NADP-glutamate dehydrogenase-less mutant strain. The gdh gus mutant is a glutamate auxotroph. The genetic analysis of the gus mutant showed that the GOGAT-less phenotype is due to the presence of two loosely linked mutations. Evidence is presented which suggests the possibility that S. cerevisiae has two GOGAT activities, designated GOGAT A and GOGAT B. These activities can be distinguished by their pH optima and by their regulation by glutamate. Furthermore, one of the mutations responsible for the GOGAT-less phenotype affected GOGAT A activity, while the other mutation affected GOGAT B activity. PMID:2687252

  16. Activity of Fusidic Acid Tested against Staphylococci Isolated from Patients in U.S. Medical Centers in 2014

    PubMed Central

    Farrell, David J.; Mendes, Rodrigo E.; Castanheira, Mariana

    2016-01-01

    Fusidic acid (FA) activity was evaluated against 2,002 clinical staphylococcal isolates collected in U.S. hospitals during 2014. FA (MIC50/90, 0.12/0.12 μg/ml) inhibited 99.8% of Staphylococcus aureus isolates at ≤1 μg/ml. Only four S. aureus isolates displayed FA values of >2 μg/ml (three strains with fusC and one with an L461K substitution in fusA), and they were isolated from patients in four states. In conclusion, FA demonstrated sustained, potent activity against this recent collection of U.S. staphylococci. PMID:27021326

  17. Structure and antioxidant activity of phenolic compounds isolated from the edible fruits and stem bark of Harpephyllum caffrum.

    PubMed

    Moodley, Roshila; Koorbanally, Neil A; Shahidul Islam, Md; Jonnalagadda, Sreekanth B

    2014-01-01

    Antioxidant activity in edible fruits is an important characteristic in the choice of fruits for human consumption, and has profound influence on nutrition and health. Two pharmacologically active triterpenoids, β-sitosterol and lupeol, and the powerful flavan-3-ol antioxidant, (+)-catechin, were isolated from the edible fruits of Harpephyllum caffrum while a mixture of cardanols, an alkyl p-coumaric acid ester, and (+)-catechin were isolated from the stem bark. This is the first report of these compounds being isolated from this plant. The antioxidant capacity of (+)-catechin was higher than the other isolated compounds as well as the known antioxidant, ascorbic acid.

  18. Ultra-low-frequency vertical vibration isolator based on a two-stage beam structure for absolute gravimetry.

    PubMed

    Wang, G; Wu, K; Hu, H; Li, G; Wang, L J

    2016-10-01

    To reduce seismic and environmental vibration noise, ultra-low-frequency vertical vibration isolation systems play an important role in absolute gravimetry. For this purpose, an isolator based on a two-stage beam structure is proposed and demonstrated. The isolator has a simpler and more robust structure than the present ultra-low-frequency vertical active vibration isolators. In the system, two beams are connected to a frame using flexural pivots. The upper beam is suspended from the frame with a normal hex spring and the lower beam is suspended from the upper one using a zero-length spring. The pivot of the upper beam is not vertically above the pivot of the lower beam. With this special design, the attachment points of the zero-length spring to the beams can be moved to adjust the effective stiffness. A photoelectric detector is used to detect the angle between the two beams, and a voice coil actuator attached to the upper beam is controlled by a feedback circuit to keep the angle at a fixed value. The system can achieve a natural period of 100 s by carefully moving the attachment points of the zero-length spring to the beams and tuning the feedback parameters. The system has been used as an inertial reference in the T-1 absolute gravimeter. The experiment results demonstrate that the system has significant vibration isolation performance that holds promise in applications such as absolute gravimeters.

  19. Ultra-low-frequency vertical vibration isolator based on a two-stage beam structure for absolute gravimetry

    NASA Astrophysics Data System (ADS)

    Wang, G.; Wu, K.; Hu, H.; Li, G.; Wang, L. J.

    2016-10-01

    To reduce seismic and environmental vibration noise, ultra-low-frequency vertical vibration isolation systems play an important role in absolute gravimetry. For this purpose, an isolator based on a two-stage beam structure is proposed and demonstrated. The isolator has a simpler and more robust structure than the present ultra-low-frequency vertical active vibration isolators. In the system, two beams are connected to a frame using flexural pivots. The upper beam is suspended from the frame with a normal hex spring and the lower beam is suspended from the upper one using a zero-length spring. The pivot of the upper beam is not vertically above the pivot of the lower beam. With this special design, the attachment points of the zero-length spring to the beams can be moved to adjust the effective stiffness. A photoelectric detector is used to detect the angle between the two beams, and a voice coil actuator attached to the upper beam is controlled by a feedback circuit to keep the angle at a fixed value. The system can achieve a natural period of 100 s by carefully moving the attachment points of the zero-length spring to the beams and tuning the feedback parameters. The system has been used as an inertial reference in the T-1 absolute gravimeter. The experiment results demonstrate that the system has significant vibration isolation performance that holds promise in applications such as absolute gravimeters.

  20. Cold active hydrolytic enzymes production by psychrotrophic Bacilli isolated from three sub-glacial lakes of NW Indian Himalayas.

    PubMed

    Yadav, Ajar Nath; Sachan, Shashwati Ghosh; Verma, Priyanka; Kaushik, Rajeev; Saxena, Anil Kumar

    2016-03-01

    The diversity of culturable, cold-active enzymes producing Bacilli was investigated from three sub-glacial lakes of north western Indian Himalayas. Amplified ribosomal DNA restriction analysis (ARDRA) using three restriction enzymes Alu I, Msp I, and Hae III led to the clustering of 136 Bacilli into 26, 23, and 22 clusters at 75% similarity index from Chandratal Lake, Dashair Lake, and Pangong Lake, respectively. Phylogenetic analysis based on 16S rRNA gene sequencing led to the identification of 35 Bacilli that could be grouped in seven families viz.: Bacillaceae (48%), Staphylococcaceae (14%), Bacillales incertae sedis (13%), Planococcaceae (12%), Paenibacillaceae (9%), Sporolactobacillaceae (3%), and Carnobacteriaceae (1%), which included twelve different genera Bacillus, Desemzia, Exiguobacterium, Jeotgalicoccus, Lysinibacillus, Paenibacillus, Planococcus, Pontibacillus, Sinobaca, Sporosarcina, Staphylococcus, and Virgibacillus. Based on their optimal temperature for growth, 35 Bacilli were grouped as psychrophilic (11 strains), psychrotrophic (17 strains), or psychrotolerant (7 strains), respectively. The representative isolates from each cluster were screened for cold-active enzyme activities. Amylase, β-glucosidase, pectinase, and protease activities at 4 °C were detected in more than 80% of the strains while approximately 40, 31, 23, 14, 11, and 9% of strains possessed cellulase, xylanase, β-galactosidase, laccase, chitinase, and lipase activity, respectively. Among 35 Bacilli, Bacillus amyloliquefaciens, Bacillus marisflavi, Exiguobacterium indicum, Paenibacillus terrae, Pontibacillus sp., Sporosarcina globispora, and Sporosarcina psychrophila were efficient producers of different cold-active enzymes. These cold-adapted Bacilli could play an important role in industrial and agricultural processes.

  1. Lipoxygenase Inhibitory Activity of Korean Indigenous Mushroom Extracts and Isolation of an Active Compound from Phellinus baumii

    PubMed Central

    Lee, Seung Woong; Song, Ja-Gyeong; Hwang, Byung Soon; Kim, Dae-Won; Lee, Yoon-Ju; Woo, E-Eum; Kim, Ji-Yul; Lee, In-Kyoung

    2014-01-01

    We investigated a total of 335 samples of Korean native mushroom extracts as part of our lipoxygenase (LOX) inhibitor screening program. Among the mushroom-methanolic extracts we investigated, 35 exhibited an inhibitory activity greater than 30% against LOX at a concentration of 100 µg/mL. Especially, Collybia maculata, Tylopilus neofelleus, Strobilomyces confusus, Phellinus gilvus, P. linteus, P. baumii, and Inonotus mikadoi exhibited relatively potent LOX inhibitory activities of 73.3%, 51.6%, 52.4%, 66.7%, 59.5%, 100.0%, and 85.2%, respectively. Bioassay-guided fractionation led to the isolation of inoscavin A from the methanolic extract of P. baumii, which showed the most potent activity and was identified by spectroscopic methods. Specifically, inoscavin A exhibited potent LOX inhibitory activity with an IC50 value of 6.8 µM. PMID:25071389

  2. Evaluation of antiviral activity of compounds isolated from Ranunculus sieboldii and Ranunculus sceleratus.

    PubMed

    Li, Haibo; Zhou, Changxin; Pan, Yunxue; Gao, Xiaozhong; Wu, Xiumei; Bai, Hua; Zhou, Linfu; Chen, Zhi; Zhang, Shuili; Shi, Shuyun; Luo, Jiali; Xu, Juanhua; Chen, Liurong; Zheng, Xiaoxiang; Zhao, Yu

    2005-12-01

    Nineteen compounds isolated from Ranunculus sieboldii and Ranunculus sceleratus were tested for inhibitory effects on hepatitis B virus (HBV) and Herpes simplex virus type-1 (HSV-1). The results showed that apigenin 4'- O- alpha-rhamnopyranoside, apigenin 7- O- beta-glucopyranosyl-4'- O- alpha-rhamnopyranoside, tricin 7- O- beta-glucopyranoside, tricin, and isoscopoletin possessed inhibitory activity against HBV replication. Protocatechuyl aldehyde exhibited an inhibiting activity on HSV-1 replication. It is therefore suggested that further investigations on these bioactive compounds might be needed to discover and develop new antiviral agents.

  3. Evaluation of hepatoprotective effect of Gentiana olivieri herbs on subacute administration and isolation of active principle.

    PubMed

    Orhan, Didem Deliorman; Aslan, Mustafa; Aktay, Göknur; Ergun, Ender; Yesilada, Erdem; Ergun, Fatma

    2003-04-04

    Hepatoprotective effect of Gentiana olivieri Griseb. (Gentianaceae) flowering herbs on subacute administration were studied using in vivo models in rats. For the activity assessment on carbon tetrachloride-induced hepatic damage following biochemical parameters were evaluated; plasma and hepatic tissue malondialdehyde formation, and liver tissue glutathione level, as well as plasma transaminase enzyme levels (aspartate transferase and alanine transferase). Results of biochemical tests were also confirmed by histopathological examination. Through bioassay-guided fractionation procedures isoorientin, a known C-glycosylflavone, was isolated from the ethyl acetate fraction as the active antihepatotoxic constituent by silica gel column chromatography. Isoorientin exhibited significant hepatoprotective effect at 15 mg/kg b.w. dose.

  4. Safety assessment of discharge chute isolation barrier preparation and installation activities. Revision 3

    SciTech Connect

    Meichle, R.H.

    1994-11-08

    This revision adds a section addressing impacts of dropping surfacing tool and rack cutter on the basin floor, and corrects typographical errors. The safety assessment is made for the activities for the preparation and installation of the discharge chute isolation barriers. The safety assessment includes a hazard assessment and comparisons of potential accidents/events to those addressed by the current safety basis documentation. No significant hazards were identified. An evaluation against the USQ evaluation questions was made and the determination made that the activities do not represent a USQ. Hazard categorization techniques were used to provide a basis for readiness review classifications.

  5. Screening for cytotoxic activity of extracts and isolated alkaloids from bulbs of Hippeastrum vittatum.

    PubMed

    Silva, A F S; de Andrade, J P; Machado, K R B; Rocha, A B; Apel, M A; Sobral, M E G; Henriques, A T; Zuanazzi, J A S

    2008-10-01

    The dichloromethane and n-butanol extracts obtained from fresh bulbs of Hippeastrum vittatum (Amaryllidaceae), collected in Southern Brazil, were evaluated for their cytotoxic activity in vitro against five human cell lines (HT29 colon adenocarcinoma, H460 non-small cell lung carcinoma, RXF393 renal cell carcinoma, MCF7 breast cancer, and OVCAR3 epithelial ovarian cancer), using the sulphorhodamine B assay. Both extracts showed potential antiproliferative activity. From CH(2)Cl(2) fraction, three alkaloids were isolated: lycorine, vittatine and montanine. The two last compounds were submitted to the antiproliferative assay and the highest level of cytotoxicity was found for the alkaloid montanine.

  6. Evaluation of actuators for the SDOF and MDOF active microgravity isolation systems

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The University of Virginia examined the design of actuators for both single-degree-of-freedom (SDOF) and multiple-degree-of-freedom (MDOF) active microgravity isolation systems. For SDOF systems, two actuators were considered: a special large gap magnetic actuator and a large stroke Lorentz actuator. The magnetic actuator was viewed to be of greater difficulty than the Lorentz actuator with little compelling technical advantage and was dropped from consideration. A Lorentz actuator was designed and built for the SDOF test rig using magnetic circuit and finite element analysis. The design and some experimental results are discussed. The University also examined the design of actuators for MDOF isolation systems. This includes design of an integrated 1 cm gap 6-DOF noncontacting magnetic suspension system and of a 'coarse' follower which permits the practical extension of magnetic suspension to large strokes. The proposed 'coarse' actuator was a closed kinematic chain manipulator known as a Stewart Platform. The integration of the two isolation systems together, the isolation tasks assigned to each, and possible control architectures were also explored. The results of this research are examined.

  7. Isolation, Characterization, and Antibacterial Activity of Bacteriophages Against Methicillin-Resistant Staphylococcus aureus in Pakistan

    PubMed Central

    Rasool, Muhammad Hidayat; Yousaf, Rukhsana; Siddique, Abu Baker; Saqalein, Muhammad; Khurshid, Mohsin

    2016-01-01

    Background In recent years, antibiotic resistance has been indicated as a paramount threat to public health. The use of bacteriophages appears to be a safer alternative for the control of bacterial infections. Objectives The present study aims to explore sewage water for the presence of indigenous bacteriophages, and to investigate their antibacterial potential against Methicillin-resistant Staphylococcus aureus (MRSA). Methods Bacterial isolates were first collected and identified from pus samples taken from the surgical and burn units using standard microbiological procedures. A cefoxitin disk screen test was then used and interpreted according to the clinical laboratory standards institute (CLSI) guidelines for the detection of MRSA. The sewage samples were processed and the phages enriched using S. aureus as a host organism. Turbid and clear plaques of different sizes were isolated using an overlay method, purified, and then enumerated by means of a dilution method. Results The phages exhibited good lytic activity against MRSA when tested in-vitro, and the highest activity was attained within three to six hours of phage infection. The isolated phage pq/48 was also found efficient in decreasing the bacterial count during an in-vivo trial in rabbits. A protein analysis using SDS-PAGE revealed 10 proteins of between 20 kDa and 155 kDa in size. Conclusions The overall results indicated that bacteriophages isolated from sewage exhibited excellent lytic activity against MRSA strains. In conclusion, bacteriophages can be further characterized and appear to be a promising candidate for phage therapy against MRSA in the future. PMID:27942361

  8. Diversity and Antimicrobial Activity of Culturable Endophytic Fungi Isolated from Moso Bamboo Seeds

    PubMed Central

    Cai, Chun-Ju; Fan, Li; Gao, Jian; Hou, Cheng-Lin

    2014-01-01

    Bamboos, regarded as therapeutic agents in ethnomedicine, have been used to inhibit inflammation and enhance natural immunity for a long time in Asia, and there are many bamboo associated fungi with medical and edible value. In the present study, a total of 350 fungal strains were isolated from the uncommon moso bamboo (Phyllostachys edulis) seeds for the first time. The molecular diversity of these endophytic fungi was investigated and bioactive compound producers were screened for the first time. All the fungal endophytes were categorized into 69 morphotypes according to culturable characteristics and their internal transcriber spacer (ITS) regions were analyzed by BLAST search with the NCBI database. The fungal isolates showed high diversity and were divided in Ascomycota (98.0%) and Basidiomycota (2.0%), including at least 19 genera in nine orders. Four particular genera were considered to be newly recorded bambusicolous fungi, including Leptosphaerulina, Simplicillium, Sebacina and an unknown genus in Basidiomycetes. Furthermore, inhibitory effects against clinical pathogens and phytopathogens were screened preliminarily and strains B09 (Cladosporium sp.), B34 (Curvularia sp.), B35 (undefined genus 1), B38 (Penicillium sp.) and zzz816 (Shiraia sp.) displayed broad-spectrum activity against clinical bacteria and yeasts by the agar diffusion method. The crude extracts of isolates B09, B34, B35, B38 and zzz816 under submerged fermentation, also demonstrated various levels of bioactivities against bambusicolous pathogenic fungi. This study is the first report on the antimicrobial activity of endophytic fungi associated with moso bamboo seeds, and the results show that they could be exploited as a potential source of bioactive compounds and plant defense activators. In addition, it is the first time that strains of Shiraia sp. have been isolated and cultured from moso bamboo seeds, and one of them (zzz816) could produce hypocrellin A at high yield, which is

  9. The diversity, extracellular enzymatic activities and photoprotective compounds of yeasts isolated in Antarctica

    PubMed Central

    Vaz, Aline B. M.; Rosa, Luiz H.; Vieira, Mariana L. A.; de Garcia, Virginia; Brandão, Luciana R.; Teixeira, Lia C. R. S.; Moliné, Martin; Libkind, Diego; van Broock, Maria; Rosa, Carlos A.

    2011-01-01

    The diversity of yeasts collected from different sites in Antarctica (Admiralty Bay, King George Island and Port Foster Bay and Deception Island) and their ability to produce extracellular enzymes and mycosporines were studied. Samples were collected during the austral summer season, between November 2006 and January 2007, from the rhizosphere of Deschampsia antarctica, ornithogenic (penguin guano) soil, soil, marine and lake sediments, marine water and freshwater from lakes. A total of 89 isolates belonging to the following genera were recovered: Bensingtonia, Candida, Cryptococcus, Debaryomyces, Dioszegia, Exophiala, Filobasidium, Issatchenkia (Pichia), Kodamaea, Leucosporidium, Leucosporidiella, Metschnikowia, Nadsonia, Pichia, Rhodotorula, and Sporidiobolus, and the yeast-like fungi Aureobasidium, Leuconeurospora and Microglossum. Cryptococcus victoriae was the most frequently identified species. Several species isolated in our study have been previously reported to be Antarctic psychophilic yeasts, including Cr. antarcticus, Cr. victoriae, Dioszegia hungarica and Leucosporidium scottii. The cosmopolitan yeast species A. pullulans, C. zeylanoides, D. hansenii, I. orientalis, K. ohmeri, P. guilliermondii, Rh. mucilaginosa, and S. salmonicolor were also isolated. Five possible new species were identified. Sixty percent of the yeasts had at least one detectable extracellular enzymatic activity. Cryptococcus antarcticus, D. aurantiaca, D. crocea, D. hungarica, Dioszegia sp., E. xenobiotica, Rh. glaciales, Rh. laryngis, Microglossum sp. 1 and Microglossum sp. 2 produced mycosporines. Of the yeast isolates, 41.7% produced pigments and/or mycosporines and could be considered adapted to survive in Antarctica. Most of the yeasts had extracellular enzymatic activities at 4°C and 20°C, indicating that they could be metabolically active in the sampled substrates. PMID:24031709

  10. Tunable broadband isolator based on electro-optically induced linear gratings in a nonlinear photonic crystal.

    PubMed

    Yu, Zi-Yan; Xu, Fei; Lin, Xiao-Wen; Song, Xiao-Shi; Qian, Xiao-Shi; Wang, Qin; Lu, Yan-Qing

    2010-10-15

    We theoretically propose a broadband optical isolator based on second-harmonic generation in a one-dimensional quadratic nonlinear photonic crystal (NPC) with an embedded defect. An external electric field along the z axis is applied to modulate the NPC refractive index periodically. Complete optical isolation always could be reached with the help of an external field. Influences of the defect position and thickness are discussed. The spectral and power tolerances of the isolator also have been investigated and show high contrast within a wide wavelength range at different power levels.

  11. A family 13 thioesterase isolated from an activated sludge metagenome: Insights into aromatic compounds metabolism.

    PubMed

    Sánchez-Reyez, Ayixon; Batista-García, Ramón Alberto; Valdés-García, Gilberto; Ortiz, Ernesto; Perezgasga, Lucía; Zárate-Romero, Andrés; Pastor, Nina; Folch-Mallol, Jorge Luis

    2017-03-09

    Activated sludge is produced during the treatment of sewage and industrial wastewaters. Its diverse chemical composition allows growth of a large collection of microbial phylotypes with very different physiologic and metabolic profiles. Thus, activated sludge is considered as an excellent environment to discover novel enzymes through functional metagenomics, especially activities related with degradation of environmental pollutants. Metagenomic DNA was isolated and purified from an activated sludge sample. Metagenomic libraries were subsequently constructed in Escherichia coli. Using tributyrin hydrolysis, a screening by functional analysis was conducted and a clone that showed esterase activity was isolated. Blastx analysis of the sequence of the cloned DNA revealed, among others, an ORF that encodes a putative thioesterase with 47-64% identity to GenBank CDS reported genes, similar to those in the hotdog fold thioesterase superfamily. On the basis of its amino acid similarity and its homology-modelled structure we deduced that this gene encodes an enzyme (ThYest_ar) that belongs to family TE13, with a preference for aryl-CoA substrates and a novel catalytic residue constellation. Plasmid retransformation in E. coli confirmed the clone's phenotype, and functional complementation of a paaI E. coli mutant showed preference for phenylacetate over chlorobenzene as a carbon source. This work suggests a role for TE13 family thioesterases in swimming and degradation approaches for phenyl acetic acid. Proteins 2017. © 2017 Wiley Periodicals, Inc.

  12. Streptokinase variants from Streptococcus pyogenes isolates display altered plasminogen activation characteristics - implications for pathogenesis.

    PubMed

    Cook, Simon M; Skora, Amanda; Gillen, Christine M; Walker, Mark J; McArthur, Jason D

    2012-12-01

    Streptococcus pyogenes (group A streptococcus, GAS) secretes streptokinase, a potent plasminogen activating protein. Among GAS isolates, streptokinase gene sequences (ska) are polymorphic and can be grouped into two distinct sequence clusters (termed cluster type-1 and cluster type-2) with cluster type-2 being further divided into sub-clusters type-2a and type-2b. In this study, far-UV circular dichroism spectroscopy indicated that purified streptokinase variants of each type displayed similar secondary structure. Type-2b streptokinase variants could not generate an active site in Glu-plasminogen through non-proteolytic mechanisms while all other variants had this capability. Furthermore, when compared with other streptokinase variants, type-2b variants displayed a 29- to 35-fold reduction in affinity for Glu-plasminogen. All SK variants could activate Glu-plasminogen when an activator complex was preformed with plasmin; however, type-2b and type-1 complexes were inhibited by α(2) -antiplasmin. Exchanging ska(type-2a) in the M1T1 GAS strain 5448 with ska(type-2b) caused a reduction in virulence while exchanging ska(type-2a) with ska(type-1) into 5448 produced an increase in virulence when using a mouse model of invasive disease. These findings suggest that streptokinase variants produced by GAS isolates utilize distinct plasminogen activation pathways, which directly affects the pathogenesis of this organism.

  13. Novel Antibacterial Activity of Lactococcus Lactis Subspecies Lactis Z11 Isolated from Zabady

    PubMed Central

    Enan, Gamal; Abdel-Shafi, Seham; Ouda, Sahar; Negm, Sally

    2013-01-01

    The purpose of this study was to select and characterize a probiotic bacterium with distinctive antimicrobial activities. In this respect, Lactococcus lactis subspecies lactis Z11 (L. lactis Z11) isolated from Zabady (Arabian yoghurt) inhibited other strains of lactic acid bacteria and some food-born pathogens including Listeria monocytogenes, Bacillus cereus and staphylococcus aureus. The inhibitory activity of cell free supernatant (CFS) of L. lactis Z11 isolated from zabady was lost by proteolytic enzymes, heat resistant. Consequently, the active substance(s) of CFS was characterized as a bacteriocin. This bacteriocin has been shown to consist of protein but has no lipidic or glucidic moieties in its active molecule. Its activity was stable in the pH range 2.0 to 7.0 and was not affected by organic solvents. The L. lactis Z11 bacteriocin was produced in CFS throughout the mide to the late exponential phase of growth of the producer organism and maximum bacteriocin production was obtained at initial pH 6.5 at incubation temperature of about 30°C. PMID:24151453

  14. Antiplatelet and Anticoagulant Activities of Angelica shikokiana Extract and Its Isolated Compounds.

    PubMed

    Mira, Amira; Alkhiary, Wael; Shimizu, Kuniyoshi

    2017-01-01

    Angelica shikokiana is a Japanese medicinal plant that is used traditionally in several ailments of cardiovascular diseases. However, there is no report regarding its anticoagulant or antiplatelet activities. So this study was designed to screen for such activities (anticoagulant by prothrombin time [PT], activated partial thromboplastin time, and thrombin time assays and antiplatelet activities against adenosine 5'-diphosphate [ADP] and arachidonic acid-induced platelet aggregations) for the methanol extract of the aerial part (Angelica methanol extract [AME]), its isolated coumarins, flavonoids, and flavonoid metabolites. The AME had potent anticoagulant and antiplatelet activities, and the flavonoid compounds were evidenced to be responsible for such activities. Among coumarins compounds, hyuganin C showed significant prolongation of only PT, while other coumarins were inactive. Similarly, hyuganin C and bergapten were the only active coumarins against ADP-induced platelet aggregation. Compared to the parent compounds, colonic metabolites of the flavonoids had similar anticoagulant and antiplatelet activities, while glucuronides showed sharp decreases in all studied activities. This is the first report showing that the medicinal plant A shikokiana has potent antiplatelet and anticoagulant activities.

  15. Trypanocidal and leishmanicidal activities of flavonoids isolated from Stevia satureiifolia var. satureiifolia.

    PubMed

    Beer, María Florencia; Frank, Fernanda Maria; Germán Elso, Orlando; Ernesto Bivona, Augusto; Cerny, Natacha; Giberti, Gustavo; Luis Malchiodi, Emilio; Susana Martino, Virginia; Alonso, María Rosario; Patricia Sülsen, Valeria; Cazorla, Silvia Ines

    2016-10-01

    Context Chagas' disease and leishmaniasis produce significant disability and mortality with great social and economic impact. The genus Stevia (Asteraceae) is a potential source of antiprotozoal compounds. Objective Aerial parts of four Stevia species were screened on Trypanosoma cruzi. Stevia satureiifolia (Lam.) Sch. Bip. var. satureiifolia (Asteraceae) dichloromethane extract was selected for a bioassay-guided fractionation in order to isolate its active compounds. Additionally, the antileishmanial activity and the cytotoxicity of these compounds on mammalian cells were assessed. Materials and methods The dichloromethane extract was fractionated by column chromatography. The isolated compounds were evaluated using concentrations of 0-100 μg/mL on T. cruzi epimastigotes and on Leishmania braziliensis promastigotes for 72 h, on trypomastigotes and amastigotes of T. cruzi for 24 h and 120 h, respectively. The compounds' cytotoxicity (12.5-500 μg/mL) was assessed on Vero cells by the MTT assay. The structure elucidation of each compound was performed by spectroscopic methods and HPLC analysis. Results The dichloromethane extracts of Stevia species showed significant activity on T. cruzi epimastigotes. The flavonoids eupatorin (1.3%), cirsimaritin (1.9%) and 5-desmethylsinensetin (1.5%) were isolated from S. satureiifolia var. satureiifolia extract. Eupatorin and 5-desmethylsinensetin showed IC50 values of 0.2 and 0.4 μg/mL on T. cruzi epimastigotes and 61.8 and 75.1 μg/mL on trypomastigotes, respectively. The flavonoid 5-desmethylsinensetin showed moderate activity against T. cruzi amastigotes (IC50  value = 78.7 μg/mL) and was the most active compound on L. braziliensis promastigotes (IC50  value = 37.0 μg/mL). Neither of the flavonoids showed cytotoxicity on Vero cells, up to a concentration of 500 μg/mL.

  16. Single-mode waveguide optical isolator based on direction-dependent cutoff frequency.

    PubMed

    Tang, Lingling; Drezdzon, Samuel M; Yoshie, Tomoyuki

    2008-09-29

    A single-mode-waveguide optical isolator based on propagation direction dependent cut-off frequency is proposed. The isolation bandwidth is the difference between the cut-off frequencies of the lowest forward and backward propagating modes. Perturbation theory is used for analyzing the correlation between the material distribution and the bandwidth. The mode profile determines an appropriate distribution of non-reciprocal materials.

  17. Eoetvoesia caeni gen. nov., sp. nov., isolated from an activated sludge system treating coke plant effluent.

    PubMed

    Felföldi, Tamás; Vengring, Anita; Kéki, Zsuzsa; Márialigeti, Károly; Schumann, Peter; Tóth, Erika M

    2014-06-01

    A novel bacterium, PB3-7B(T), was isolated on phenol-supplemented inorganic growth medium from a laboratory-scale wastewater purification system that treated coke plant effluent. 16S rRNA gene sequence analysis revealed that strain PB3-7B(T) belonged to the family Alcaligenaceae and showed the highest pairwise sequence similarity to Parapusillimonas granuli Ch07(T) (97.5%), Candidimonas bauzanensis BZ59(T) (97.3%) and Pusillimonas noertemannii BN9(T) (97.2%). Strain PB3-7B(T) was rod-shaped, motile and oxidase- and catalase-positive. The predominant fatty acids were C(16 : 0), C(17 : 0) cyclo, C(19 : 0) cyclo ω8c and C(14 : 0) 3-OH, and the major respiratory quinone was Q-8. The G+C content of the genomic DNA of strain PB3-7B(T) was 59.7 mol%. The novel bacterium can be distinguished from closely related type strains based on its urease activity and the capacity for assimilation of glycerol and amygdalin. On the basis of the phenotypic, chemotaxonomic and molecular data, strain PB3-7B(T) is considered to represent a new genus and species, for which the name Eoetvoesia caeni gen. nov., sp. nov. is proposed. The type strain of Eoetvoesia caeni is PB3-7B(T) ( = DSM 25520(T) = NCAIM B 02512(T)).

  18. RNase one gene isolation, expression, and affinity purification models research experimental progression and culminates with guided inquiry-based experiments.

    PubMed

    Bailey, Cheryl P

    2009-01-01

    This new biochemistry laboratory course moves through a progression of experiments that generates a platform for guided inquiry-based experiments. RNase One gene is isolated from prokaryotic genomic DNA, expressed as a tagged protein, affinity purified, and tested for activity and substrate specificity. Student pairs present detailed explanations of materials and methods and the semester culminates in a poster session. Experimental plans take into account the expense and time required to move from gene isolation to enzyme assays. This combination of instructor-guided and student-designed experiments is a manageable foray into guided inquiry-based learning in a biochemistry laboratory course, while providing a cohesive story and context for individual experiments.

  19. Biological activities and potential health benefit effects of polysaccharides isolated from Lycium barbarum L.

    PubMed

    Jin, Mingliang; Huang, Qingsheng; Zhao, Ke; Shang, Peng

    2013-03-01

    Recently, isolation and investigation of novel ingredients with biological activities and health benefit effects from natural resources have attracted a great deal of attention. The fruit of Lycium barbarum L., a well-known Chinese herbal medicine as well as valuable nourishing tonic, has been used historically as antipyretic, anti-inflammation and anti-senile agent for thousands of years. Modern pharmacological experiments have proved that polysaccharide is one of the major ingredients responsible for those biological activities in L. barbarum. It has been demonstrated that L. barbarum polysaccharides had various important biological activities, such as antioxidant, immunomodulation, antitumor, neuroprotection, radioprotection, anti-diabetes, hepatoprotection, anti-osteoporosis and antifatigue. The purpose of the present review is to summarize previous and current references regarding biological activities as well as potential health benefits of L. barbarum polysaccharides.

  20. [Antibacterial activity of polyphenolic compounds isolated from plants of Geraniaceae and Rosaceae families].

    PubMed

    Nikitina, V S; Kuz'mina, L Iu; Melent'ev, A I; Shendel', G V

    2007-01-01

    Polyphenolic compounds present in extracts of plants belonging to the families Geraniaceae (blood-red cranesbill, wood cranesbill, meadow cranesbill, and alfilaria) and Rosaceae (red raspberry, European dewberry, and tormentil) have been tested for their activity against gram-positive and gram-negative bacteria of the genera Azotobacter, Bacillus, and Pseudomonas. The bacteriostatic activity exhibited some species-related features and depended on the polarity of the extracting agent. The bacteriostatic activity of plant-derived phenolic compounds correlated with their antioxidant potential. The plants of the families Geraniaceae and Rosaceae offer promise as a source of raw material for isolation of polyphenolic compounds exhibiting bactericidal activity, including against opportunistic pathogens (B. cereus, E. coli, P. aeruginosa, and S. aureus strains).

  1. Isolation, identification and antimicrobial activities of two secondary metabolites of Talaromyces verruculosus.

    PubMed

    Miao, Fang; Yang, Rui; Chen, Dong-Dong; Wang, Ying; Qin, Bao-Fu; Yang, Xin-Juan; Zhou, Le

    2012-11-28

    From the ethyl acetate extract of the culture broth of Talaromyces verruculosus, a rhizosphere fungus of Stellera chamaejasme L., (-)-8-hydroxy-3-(4-hydroxypentyl)-3,4-dihydroisocoumarin (1) and (E)-3-(2,5-dioxo-3-(propan-2-ylidene)pyrrolidin-1-yl)acrylic acid (2) were isolated and evaluated for their antimicrobial activities. Their structures were elucidated by UV, IR, MS, 1H-NMR, 13C-NMR and 2D NMR spectra. Compound 1 exhibited the significant activities in vitro against two strains of bacteria and four strains of fungi. Compound 2 gave slight activities on the fungi at 100 µg mL(-1), but no activities on the bacteria. Compound 1 should be considered as a new lead or model compound to develop new isocoumarin antimicrobial agents.

  2. Antifungal activity of extracts and prenylated coumarins isolated from Baccharis darwinii Hook & Arn. (Asteraceae).

    PubMed

    Kurdelas, Rita R; Lima, Beatriz; Tapia, Alejandro; Feresin, Gabriela Egly; Gonzalez Sierra, Manuel; Rodríguez, María Victoria; Zacchino, Susana; Enriz, Ricardo D; Freile, Monica L

    2010-07-13

    The petroleum ether extract of Baccharis darwinii showed activity against Cryptococcus neoformans and dermatophytes. Bioactivity-guided fractionation of Baccharis darwinii has resulted in the isolation of three coumarins: 5'-hydroxy aurapten (anisocoumarin H, 1), aurapten (7-geranyloxycoumarin, 2) and 5'-oxoaurapten (diversinin, 3). The structures of these compounds were characterized by spectroscopic methods. These compounds were evaluated for their antimicrobialactivity against a panel of each, bacteria and fungi. Compound 3 showed the best activities against Microsporum gypseum, Trichophyton rubrum and Trichophyton mentagrophytes with MICs = 15.6 microg/mL, followed by compound 1 whose MICs against the same fungi were 62.5 microg/mL. In addition they showed fungicidal rather than fungistatic activity. Both compounds showed moderate activity (MICs = 125 microg/mL) against Cryptococcus neoformans. This is the first report of the presence of compound 1 in B. darwinii.

  3. Activation of macrophages by an exopolysaccharide isolated from Antarctic Psychrobacter sp. B-3

    NASA Astrophysics Data System (ADS)

    Yu, Leiye; Sun, Guojie; Wei, Jingfang; Wang, Yingze; Du, Chao; Li, Jiang

    2016-09-01

    An exopolysaccharide (EPS) was isolated and purified from an Antarctic psychrophilic bacterium B-3, identified as Psychrobacter sp., and the activation of RAW264.7 cells by B-3 EPS was investigated. The results show that B-3 EPS, over a certain concentration range, promoted cell viability, nitric oxide production, tumor necrosis factor (TNF)α secretion, and phagocytic ability. Furthermore, TAK-242, an inhibitor of the toll-like receptor 4 (TLR4) significantly reduced nitric oxide production by these cells after stimulation with B-3 EPS. Moreover, B-3 EPS induced p65 phosphorylation and IκBα degradation in these cells. In conclusion, B-3 EPS might have activated RAW264.7 cells by combining with TLR4 on cell surface and triggering activation of NF-κB signaling pathways, implying that this EPS could activate macrophages and regulate initial immune response.

  4. Antimycobacterial activity of a Brevibacillus laterosporusstrain isolated from a moroccan soil.

    PubMed

    Hassi, Mohammed; Guendouzi, Souraya El; Haggoud, Abdelleatif; David, Susana; Ibnsouda, Saad; Houari, Abdellah; Iraqui, Mohammed

    2012-10-01

    The treatment of tuberculosis has become more difficult with the worldwide spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of Mycobacterium tuberculosis. Moreover, the prevalence of human disease caused by atypical mycobacteria has also increased in the past two decades and has further complicated the problem of the treatment of mycobacterial infections. It is therefore urgent to develop new highly active molecules against these bacteria. The present study reports the isolation from a Moroccan soil of a Bacillus strain that exhibits an important antimycobacterial activity. The strain was identified as Brevibacillus laterosporus using DNA sequencing of the 16S ribosomal RNA gene. The antimycobacterial activity was assigned to a substance with a protein nature. This nature was revealed using a liquid-liquid extraction with organic solvents, precipitation with ammonium sulfate and treatment with a protease. This study suggested the identification and the characterization of this active metabolite enabling therapeutic investigations further.

  5. Comparative in vitro activity of antimycotic agents against pathogenic vaginal yeast isolates.

    PubMed

    Lynch, M E; Sobel, J D

    1994-01-01

    Although numerous antimycotic agents are available for the treatment of yeast vaginitis there is little comparative data on the in vitro activity of these drugs. In the present two-part study, in vitro macro-broth dilution sensitivity tests were performed on a total of 377 clinical vaginal yeast isolates of nine different species. Antimycotics surveyed included amphotericin B, 5-fluorocytosine and eight azole derivatives. Results show that all vaginal Candida albicans isolates were uniformly sensitive at low concentration to all 10 antimycotics tested. However, non-albicans species, especially Candida glabrata and Saccharomyces cerevisiae, manifested several-fold increases in minimal inhibitory concentrations to all azoles tested except butoconazole. In particular, the in vitro potency of fluconazole and terconazole against species other than C. albicans was relatively poor, whereas the drugs demonstrating the best activity were itraconazole, butoconazole and saperconazole. Susceptibility testing of vaginal C. albicans isolates is not routinely indicated, even in patients with recurrent vaginitis and should be reserved for selected organisms, especially non-albicans species, in patients with clinical failure only.

  6. In Vitro Antifungal Activity of Epigallocatechin 3-O-Gallate against Clinical Isolates of Dermatophytes

    PubMed Central

    Park, Bong Joo; Taguchi, Hideaki; Kamei, Katsuhiko; Matsuzawa, Tetsuhiro; Hyon, Suong-Hyu

    2011-01-01

    Previously, we reported that epigallocatechin 3-O-gallate (EGCg) has growth-inhibitory effect on clinical isolates of Candida species. In this study, we investigated the antifungal activity of EGCg and antifungal agents against thirty-five of dermatophytes clinically isolated by the international guidelines (M38-A2). All isolates exhibited good susceptibility to EGCg (MIC50, 2-4 µg/mL, MIC90, 4-8 µg/mL, and geometric mean (GM) MICs, 3.36-4 µg/mL) than those of fluconazole (MIC50, 2-16 µg/mL, MIC90, 4-32 µg/mL, and GM MICs, 3.45-25.8 µg/mL) and flucytosin (MIC50, MIC90, and GM MICs, >64 µg/mL), although they were less susceptible to other antifungal agents, such as amphotericin B, itraconazole, and miconazole. These activities of EGCg were approximately 4-fold higher than those of fluconazole, and were 4 to 16-fold higher than flucytosin. This result indicates that EGCg can inhibit pathogenic dermatophyte species. Therefore, we suggest that EGCg may be effectively used solely as a possible agent or combined with other antifungal agents for antifungal therapy in dermatophytosis. PMID:21488200

  7. Insecticidal Activity of Bacillus thuringiensis Strains Isolated from Soil and Water

    PubMed Central

    Konecka, Edyta; Baranek, Jakub; Hrycak, Anita; Kaznowski, Adam

    2012-01-01

    We attempted to search novel Bacillus thuringiensis strains that produce crystals with potential utility in plant protection and with higher activity than strains already used in biopesticide production. Seven B. thuringiensis soil and water isolates were used in the research. We predicted the toxicity of their crystals by cry gene identification employing PCR method. The isolate MPU B63 with interesting, according to us, genes content was used in evaluating its crystal toxicity against Cydia pomonella caterpillars. The strain MPU B63 was cultured from water sample and had cry1Ab, cry1B, and cry15 genes. The LC50 crystals of MPU B63 were compared to LC50 of commercial bioinsecticide Foray determined against C. pomonella (codling moth). The activity of MPU B63 inclusions against codling moth larvae was approximately 24-fold higher than that of Foray. The results are a promising introduction for further study evaluating the potential usefulness of isolate MPU B63 crystals in plant protection. PMID:22666145

  8. Data base management systems activities

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The Data Management System-1100 is designed to operate in conjunction with the UNIVAC 1100 Series Operating System on any 1100 Series computer. DMS-1100 is divided into the following four major software components: (1) Data Definition Languages (DDL); (2) Data Management Routine (DMR); (3) Data Manipulation Languages (DML); and (4) Data Base Utilities (DBU). These software components are described in detail.

  9. On-chip waveguide isolator based on bismuth iron garnet operating via nonreciprocal single-mode cutoff.

    PubMed

    Drezdzon, Samuel M; Yoshie, Tomoyuki

    2009-05-25

    We analyze an on-chip optical isolator based on direction dependent single-mode cutoff, which is described in 1D and 2D momentum space. Isolation is shown using 3D finite difference time domain (FDTD) where the magnetization is represented by imaginary off-diagonal permittivity tensor elements. The isolator designs are optimized using perturbation theory, which successfully predicts increased isolation for rib waveguides and structures with non-magnetic dielectric layers. Our isolators are based on bismuth iron garnet and its compatible substrates; an isolation ratio of 10.7 dB/mm is achieved for TM modes.

  10. Enzymatic activity of lactic acid bacteria (with antimicrobial properties) isolated from a traditional Spanish cheese.

    PubMed

    González, Leticia; Sacristán, Noelia; Arenas, Ricardo; Fresno, José M; Eugenia Tornadijo, M

    2010-08-01

    Twenty-four strains of lactic acid bacteria (LAB) isolated from a traditional Spanish cheese (Genestoso cheese) were evaluated for their enzymatic activities (acidifying and proteolytic abilities and carboxypeptidase, aminopeptidase, dipeptidase, caseinolytic and esterase activities), in order to select indigenous strains of technical interest for the manufacture of cheese. These strains were selected on the basis of their antimicrobial activity relative to five reference strains and were identified as Lactococcus lactis subsp. lactis (thirteen strains), Leuconostoc mesenteroides (two strains), Leuconostoc pseudomesenteroides (one strain), Lactobacillus paracasei (two strains), Lactobacillus plantarum (one strain) and Enterococcus faecalis (five strains). Lactococcus strains were those that showed the greatest degree of acidifying and proteolytic activity. The cell-free extracts (CFE) of L. paracasei exhibited the highest level of aminopeptidase activity. The highest level of caseinolytic activity was shown by the CFE of one strain of L. lactis. High values were also obtained with the CFE of Lactobacillus and of several Leuconostoc. The highest level of dipeptidase activity was found amongst the strains of L. lactis. Carboxypeptidase activity was generally very low or undetectable for the majority of strains. The greatest degree of esterolytic activity was detected for Enterococcus.

  11. Antimicrobial activity and genetic profile of Enteroccoci isolated from hoopoes uropygial gland.

    PubMed

    Ruiz-Rodríguez, Magdalena; Valdivia, Eva; Martín-Vivaldi, Manuel; Martín-Platero, Antonio M; Martínez-Bueno, Manuel; Méndez, María; Peralta-Sánchez, Juan M; Soler, Juan J

    2012-01-01

    Symbiotic microorganisms may be directly transferred from parents to offspring or acquired from a particular environment that animals may be able to select. If benefits for hosts vary among microbial strains, natural selection may favour hosts holding the most beneficial one. Enterococci symbionts living in the hoopoe (Upupa epops) uropygial gland are able to synthesise bacteriocins (antimicrobial peptides that inhibit the growth of competitor bacteria). We explored variability in genetic profile (through RAPD-PCR analyses) and antimicrobial properties (by performing antagonistic tests against ten bacterial indicator strains) of the different isolates obtained from the uropygial glands of hoopoe females and nestlings. We found that the genetic profile of bacterial isolates was related to antimicrobial activity, as well as to individual host identity and the nest from which samples were obtained. This association suggest that variation in the inhibitory capacity of Enterococci symbionts should be under selection.

  12. Antimicrobial Activity and Genetic Profile of Enteroccoci Isolated from Hoopoes Uropygial Gland

    PubMed Central

    Ruiz-Rodríguez, Magdalena; Valdivia, Eva; Martín-Vivaldi, Manuel; Martín-Platero, Antonio M.; Martínez-Bueno, Manuel; Méndez, María; Peralta-Sánchez, Juan M.; Soler, Juan J.

    2012-01-01

    Symbiotic microorganisms may be directly transferred from parents to offspring or acquired from a particular environment that animals may be able to select. If benefits for hosts vary among microbial strains, natural selection may favour hosts holding the most beneficial one. Enterococci symbionts living in the hoopoe (Upupa epops) uropygial gland are able to synthesise bacteriocins (antimicrobial peptides that inhibit the growth of competitor bacteria). We explored variability in genetic profile (through RAPD-PCR analyses) and antimicrobial properties (by performing antagonistic tests against ten bacterial indicator strains) of the different isolates obtained from the uropygial glands of hoopoe females and nestlings. We found that the genetic profile of bacterial isolates was related to antimicrobial activity, as well as to individual host identity and the nest from which samples were obtained. This association suggest that variation in the inhibitory capacity of Enterococci symbionts should be under selection. PMID:22911858

  13. Fc gamma-receptor activity of isolated human placental syncytiotrophoblast plasma membrane.

    PubMed Central

    Brown, P J; Johnson, P M

    1981-01-01

    Fc gamma-receptor activity of isolated human placental syncytiotrophoblast microvillous plasma membrane (StMPM) vesicle preparations has been determined in an immunoradiometric assay using Sepharose-immobilized protein A to separate free 125I-labelled human IgG from membrane-bound 125I-IgG. This receptor assay has been optimalized in terms of buffer pH and molarity, and used to demonstrate that prior 60 min washing of isolated membranes in 3 M KCl to remove extrinsic membrane-bound protein substantially increases the membrane-binding capacity for IgG. Inhibition studies have determined the syncytiotrophoblast Fc gamma-receptor equilibrium constant for association (Ka) as 4.0 x 10(7) M-1 at 37 degrees and the number of available Fc gamma-receptor sites as 1.5 x 10(14) per mg membrane protein. PMID:7461733

  14. Latency is the major determinant of UDP-glucuronosyltransferase activity in isolated hepatocytes.

    PubMed

    Bánhegyi, G; Garzó, T; Fulceri, R; Benedetti, A; Mandl, J

    1993-08-09

    The glucuronidation of p-nitrophenol was measured in intact, saponin- and alamethicin-treated isolated mouse hepatocytes. In saponin-permeabilized cells the elevation of extrareticular UDP-glucuronic acid concentration enhanced the rate of glucuronidation threefold. When intracellular membranes were also permeabilized by alamethicin, a further tenfold increase in the glucuronidation of p-nitrophenol was present. Parallel measurements of the ER mannose 6-phosphatase activity revealed that saponin selectively permeabilized the plasma membrane, whereas alamethicin permeabilized both plasma membrane and ER membranes. The inhibition of p-nitrophenol glucuronidation by dbcAMP in intact hepatocytes was still present in saponin-treated cells and disappeared in alamethicin-permeabilized hepatocytes. It is suggested that the permeability of the endoplasmic reticulum membrane is a major determinant of glucuronidation not only in microsomes but in isolated hepatocytes as well.

  15. Occurrence and genetic diversity of Bacillus anthracis strains isolated in an active wool-cleaning factory.

    PubMed

    Wattiau, Pierre; Klee, Silke R; Fretin, David; Van Hessche, Mieke; Ménart, Marie; Franz, Tatjana; Chasseur, Camille; Butaye, Patrick; Imberechts, Hein

    2008-07-01

    Culturable microorganisms from various samples taken at an active factory performing wool and goat hair cleaning were isolated and analyzed. Bacillus anthracis was found i