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Sample records for potential bioactive materials

  1. Porous bioactive materials

    NASA Astrophysics Data System (ADS)

    Zhang, Kai

    Bioactive materials chemically bond to tissues through the development of biologically active apatite. Porous structures in biomaterials are designed to enhance bioactivity, grow artificial tissues and achieve better integration with host tissues in the body. The goal of this research is to design, fabricate and characterize novel porous bioactive materials. 3D ordered macroporous bioactive glasses (3DOM-BGs, pore size: 200--1000 nm) were prepared using a sol-gel process and colloidal crystal templates. 3DOM-BGs are more bioactive and degradable than mesoporous (pore size <50 nm) sol-gel BGs in simulated body fluid (SBF). Apatite formation and 3DOM-BG degradation rates increased with the decrease of soaking ratio. Apatite induction time in SBF increased with 3DOM-BG calcination temperature (600--800°C). Apatite formation and 3DOMBG degradation were slightly enhanced for a phosphate containing composition. Large 3DOM-BG particles formed less apatite and degraded less completely as compared with small particles. An increase in macropore size slowed down 3DOM-BG degradation and apatite formation processes. After heating the converted apatite at a temperature higher than 700°C, highly crystalline hydroxyapatite and a minor tri-calcium phosphate phase formed. 3DOM-BGs have potential applications as bone/periodontal fillers, and drugs and biological factors delivery agents. Anchoring artificial soft tissues (e.g., cartilage) to native bone presents a challenge. Porous polymer/bioactive glass composites are candidate materials for engineering artificial soft tissue/bone interfaces. Porous composites consisting of polymer matrices (e.g., polysulfone, polylactide, and polyurethane) and bioactive glass particles were prepared by polymer phase separation techniques adapted to include ceramic particles. Composites (thickness: 200--500 mum) have asymmetric structures with dense top layers and porous structures beneath. Porous structures consist of large pores (>100 mum) in a

  2. Bioactive hydrogel-nanosilica hybrid materials: a potential injectable scaffold for bone tissue engineering.

    PubMed

    Lewandowska-Łańcucka, Joanna; Fiejdasz, Sylwia; Rodzik, Łucja; Kozieł, Marcin; Nowakowska, Maria

    2015-02-10

    Novel bioactive organic-inorganic hybrid materials that can serve as injectable hydrogel systems for bone tissue regeneration were obtained. The silica nanoparticles (SiNP) prepared in situ by the Stöber method were dispersed in collagen, collagen-chitosan or chitosan sols, which were then subsequently crosslinked. Laser scanning confocal microscopy studies, in which fluorescent SiNP were applied, and SEM images indicated that the nanosilica particles were distributed in the whole volume of the hydrogel matrix. In vitro studies on fibroblast cell viability indicated that the hybrid materials are biocompatible. The silica nanoparticles dispersed in the biopolymer matrix had a positive effect on cell viability. Studies on the mineralization process under simulated body fluid (SBF) conditions confirmed the bioactivity of prepared materials. SEM images revealed mineral phase formation in the majority of the hybrid materials developed. EDS analysis indicated that these mineral phases are mainly composed of calcium and phosphorus. The XRD studies confirmed that mineral phases formed during SBF incubation of hybrid materials based on collagen are bone-like apatite minerals. The silica nanoparticles added to the hydrogel at the stage of synthesis induced the occurrence of mineralization. This process occurs not only at the surface of the material but in its entire volume, which is important for the preparation of scaffolds for bone tissue engineering. The ability of these materials to undergo in situ gelation under physiological temperature and their bioactivity as well as biocompatibility make them interesting candidates for bioactive injectable systems.

  3. Bioactive materials in endodontics.

    PubMed

    Enkel, Bénédicte; Dupas, Cécile; Armengol, Valérie; Akpe Adou, Jonas; Bosco, Julia; Daculsi, Guy; Jean, Alain; Laboux, Olivier; LeGeros, Racquel Z; Weiss, Pierre

    2008-07-01

    Endodontic treatment in dentistry is a delicate procedure and many treatment attempts fail. Despite constant development of new root canal filling techniques, the clinician is confronted with both a complex root canal system and the use of filling materials that are harmful for periapical tissues. This paper evaluates reported studies on biomaterials used in endodontics, including calcium hydroxide, mineral trioxide aggregate, calcium phosphate ceramics and calcium phosphate cements. Special emphasis is made on promising new biomaterials, such as injectable bone substitute and injectable calcium phosphate cements. These materials, which combine biocompatibility, bioactivity and rheological properties, could be good alternatives in endodontics as root canal fillers. They could also be used as drug-delivery vehicles (e.g., for antibiotics and growth factors) or as scaffolds in pulp tissue engineering.

  4. Immobilization of Trypsin in Lignocellulosic Waste Material to Produce Peptides with Bioactive Potential from Whey Protein.

    PubMed

    Bassan, Juliana Cristina; de Souza Bezerra, Thaís Milena; Peixoto, Guilherme; da Cruz, Clariana Zanutto Paulino; Galán, Julián Paul Martínez; Vaz, Aline Buda Dos Santos; Garrido, Saulo Santesso; Filice, Marco; Monti, Rubens

    2016-05-12

    In this study, trypsin (Enzyme Comission 3.4.21.4) was immobilized in a low cost, lignocellulosic support (corn cob powder-CCP) with the goal of obtaining peptides with bioactive potential from cheese whey. The pretreated support was activated with glyoxyl groups, glutaraldehyde and IDA-glyoxyl. The immobilization yields of the derivatives were higher than 83%, and the retention of catalytic activity was higher than 74%. The trypsin-glyoxyl-CCP derivative was thermally stable at 65 °C, a value that was 1090-fold higher than that obtained with the free enzyme. The trypsin-IDA-glyoxyl-CCP and trypsin-glutaraldehyde-CCP derivatives had thermal stabilities that were 883- and five-fold higher, respectively, then those obtained with the free enzyme. In the batch experiments, trypsin-IDA-glyoxyl-CCP retained 91% of its activity and had a degree of hydrolysis of 12.49%, while the values for trypsin-glyoxyl-CCP were 87% and 15.46%, respectively. The stabilized derivative trypsin-glyoxyl-CCP was also tested in an upflow packed-bed reactor. The hydrodynamic characterization of this reactor was a plug flow pattern, and the kinetics of this system provided a relative activity of 3.04 ± 0.01 U·g(-1) and an average degree of hydrolysis of 23%, which were suitable for the production of potentially bioactive peptides.

  5. Immobilization of Trypsin in Lignocellulosic Waste Material to Produce Peptides with Bioactive Potential from Whey Protein

    PubMed Central

    Bassan, Juliana Cristina; de Souza Bezerra, Thaís Milena; Peixoto, Guilherme; da Cruz, Clariana Zanutto Paulino; Galán, Julián Paul Martínez; Vaz, Aline Buda dos Santos; Garrido, Saulo Santesso; Filice, Marco; Monti, Rubens

    2016-01-01

    In this study, trypsin (Enzyme Comission 3.4.21.4) was immobilized in a low cost, lignocellulosic support (corn cob powder—CCP) with the goal of obtaining peptides with bioactive potential from cheese whey. The pretreated support was activated with glyoxyl groups, glutaraldehyde and IDA-glyoxyl. The immobilization yields of the derivatives were higher than 83%, and the retention of catalytic activity was higher than 74%. The trypsin-glyoxyl-CCP derivative was thermally stable at 65 °C, a value that was 1090-fold higher than that obtained with the free enzyme. The trypsin-IDA-glyoxyl-CCP and trypsin-glutaraldehyde-CCP derivatives had thermal stabilities that were 883- and five-fold higher, respectively, then those obtained with the free enzyme. In the batch experiments, trypsin-IDA-glyoxyl-CCP retained 91% of its activity and had a degree of hydrolysis of 12.49%, while the values for trypsin-glyoxyl-CCP were 87% and 15.46%, respectively. The stabilized derivative trypsin-glyoxyl-CCP was also tested in an upflow packed-bed reactor. The hydrodynamic characterization of this reactor was a plug flow pattern, and the kinetics of this system provided a relative activity of 3.04 ± 0.01 U·g−1 and an average degree of hydrolysis of 23%, which were suitable for the production of potentially bioactive peptides. PMID:28773482

  6. The agar diffusion scratch assay - A novel method to assess the bioactive and cytotoxic potential of new materials and compounds

    PubMed Central

    Pusnik, Mascha; Imeri, Minire; Deppierraz, Grégoire; Bruinink, Arie; Zinn, Manfred

    2016-01-01

    A profound in vitro evaluation not only of the cytotoxic but also of bioactive potential of a given compound or material is crucial for predicting potential effects in the in vivo situation. However, most of the current methods have weaknesses in either the quantitative or qualitative assessment of cytotoxicity and/or bioactivity of the test compound. Here we describe a novel assay combining the ISO 10993-5 agar diffusion test and the scratch also termed wound healing assay. In contrast to these original tests this assay is able to detect and distinguish between cytotoxic, cell migration modifying and cytotoxic plus cell migration modifying compounds, and this at higher sensitivity and in a quantitative way. PMID:26861591

  7. Evaluation of nystatin containing chitosan hydrogels as potential dual action bio-active restorative materials: in vitro approach.

    PubMed

    Perchyonok, V Tamara; Reher, Vanessa; Zhang, Shengmiao; Basson, Nicki; Grobler, Sias

    2014-11-28

    Healing is a specific biological process related to the general phenomenon of growth and tissue regeneration and is a process generally affected by several systemic conditions or as detrimental side-effects of chemotherapy- and radiotherapy-induced inflammation of the oral mucosa. The objectives of this study is to evaluate the novel chitosan based functional drug delivery systems, which can be successfully incorporated into "dual action bioactive restorative materials", capable of inducing in vitro improved wound healing prototype and containing an antibiotic, such as nystatin, krill oil as an antioxidant and hydroxyapatite as a molecular bone scaffold, which is naturally present in bone and is reported to be successfully used in promoting bone integration when implanted as well as promoting healing. The hydrogels were prepared using a protocol as previously reported by us. The physico-chemical features, including surface morphology (SEM), release behaviors, stability of the therapeutic agent-antioxidant-chitosan, were measured and compared to the earlier reported chitosan-antioxidant containing hydrogels. Structural investigations of the reactive surface of the hydrogel are reported. Release of nystatin was investigated for all newly prepared hydrogels. Bio-adhesive studies were performed in order to assess the suitability of these designer materials. Free radical defense capacity of the biomaterials was evaluated using established in vitro model. The bio-adhesive capacity of the materials in the in vitro system was tested and quantified. It was found that the favorable synergistic effect of free radical built-in defense mechanism of the new functional materials increased sustainable bio-adhesion and therefore acted as a functional multi-dimensional restorative material with potential application in wound healing in vitro.

  8. Bioactivity, cytocompatibility and thermal properties of experimental Bioglass-reinforced composites as potential root-canal filling materials.

    PubMed

    Alhashimi, Raghad Abdulrazzaq; Mannocci, Francesco; Sauro, Salvatore

    2017-05-01

    To evaluate the bioactivity and the cytocompatibility of experimental Bioglass-reinforced polyethylene-based root-canal filling materials. The thermal properties of the experimental materials were also evaluated using differential scanning calorimetry, while their radiopacity was assessed using a grey-scale value (GSV) aluminium step wedge and a phosphor plate digital system. Bioglass 45S5 (BAG), polyethylene and Strontium oxide (SrO) were used to create tailored composite fibres. The filler distribution within the composites was assessed using SEM, while their bioactivity was evaluated through infrared spectroscopy (FTIR) after storage in simulated body fluid (SBF). The radiopacity of the composite fibres and their thermal properties were determined using differential scanning calorimetry (DSC). The cytocompatibility of the experimental composites used in this study was assessed using human osteoblasts and statistically analysed using the Pairwise t-test (p<0.05). Bioglass and SrO fillers were well distributed within the resin matrix and increased both the thermal properties and the radiopacity of the polyethylene matrix. The FTIR showed a clear formation of calcium-phosphates, while, MTT and AlamrBlue tests demonstrated no deleterious effects on the metabolic activity of the osteoblast-like cells. BAG-reinforced polyethylene composites may be suitable as obturation materials for endodontic treatment. Since their low melting temperature, such innovative composites may be easily removed in case of root canal retreatment. Moreover, their biocompatibility and bioactivity may benefit proliferation of human osteoblast cells at the periapical area of the root.

  9. Bioactive materials for biomedical applications using sol-gel technology.

    PubMed

    Gupta, Radha; Kumar, Ashok

    2008-09-01

    This review paper focuses on the sol-gel technology that has been applied in many of the potential research areas and highlights the importance of sol-gel technology for preparing bioactive materials for biomedical applications. The versatility of sol-gel chemistry enables us to manipulate the characteristics of material required for particular applications. Sol-gel derived materials have proved to be good biomaterials for coating films and for the construction of super-paramagnetic nanoparticles, bioactive glasses and fiberoptic applicators for various biomedical applications. The introduction of the sol-gel route in a conventional method of preparing implants improves the mechanical strength, biocompatibility and bioactivity of scaffolds and prevents corrosion of metallic implants. The use of organically modified silanes (ORMOSILS) yields flexible and bioactive materials for soft and hard tissue replacement. A novel approach of nitric-oxide-releasing sol-gels as antibacterial coatings for reducing the infection around orthopedic implants has also been discussed.

  10. Bioactive Polymeric Materials for Tissue Repair

    PubMed Central

    Bienek, Diane R.; Tutak, Wojtek; Skrtic, Drago

    2017-01-01

    Bioactive polymeric materials based on calcium phosphates have tremendous appeal for hard tissue repair because of their well-documented biocompatibility. Amorphous calcium phosphate (ACP)-based ones additionally protect against unwanted demineralization and actively support regeneration of hard tissue minerals. Our group has been investigating the structure/composition/property relationships of ACP polymeric composites for the last two decades. Here, we present ACP’s dispersion in a polymer matrix and the fine-tuning of the resin affects the physicochemical, mechanical, and biological properties of ACP polymeric composites. These studies illustrate how the filler/resin interface and monomer/polymer molecular structure affect the material’s critical properties, such as ion release and mechanical strength. We also present evidence of the remineralization efficacy of ACP composites when exposed to accelerated acidic challenges representative of oral environment conditions. The utility of ACP has recently been extended to include airbrushing as a platform technology for fabrication of nanofiber scaffolds. These studies, focused on assessing the feasibility of incorporating ACP into various polymer fibers, also included the release kinetics of bioactive calcium and phosphate ions from nanofibers and evaluate the biorelevance of the polymeric ACP fiber networks. We also discuss the potential for future integration of the existing ACP scaffolds into therapeutic delivery systems used in the precision medicine field. PMID:28134776

  11. Incorporation of bioactive materials into integrated systems

    NASA Astrophysics Data System (ADS)

    Bunker, Bruce C.; Huber, Dale L.; Manginell, Ronald P.; Kim, Byung-Il; Boal, Andrew K.; Bachand, George D.; Rivera, Susan B.; Bauer, Joseph M.; Matzke, Carolyn M.

    2003-10-01

    Sandia is exploring two classes of integrated systems involving bioactive materials: 1) microfluidic systems that can be used to manipulate biomolecules for applications ranging from counter-terrorism to drug delivery systems, and 2) fluidic systems in which active biomolecules such as motor proteins provide specific functions such as active transport. An example of the first class involves the development of a reversible protein trap based on the integration of the thermally-switchable polymer poly(N-isopropylacrylamide)(PNIPAM) into a micro-hotplate device. To exemplify the second class, we describe the technical challenges associated with integrating microtubules and motor proteins into microfluidic systems for: 1) the active transport of nanoparticle cargo, or 2) templated growth of high-aspect ratio nanowires. These examples illustrate the functions of bioactive materials, synthesis and fabrication issues, mechanisms for switching surface chemistry and active transport, and new techniques such as the interfacial force microscope (IFM) that can be used to characterize bioactive surfaces.

  12. Surface properties of in vitro bioactive and non-bioactive sol-gel derived materials.

    PubMed

    Viitala, R; Jokinen, M; Peltola, T; Gunnelius, K; Rosenholm, J B

    2002-08-01

    The acid-base properties of several in vitro bioactive (able to form bone mineral-like calcium phosphate on their surfaces) and non-bioactive sol-gel processed oxides are studied. The amount of Lewis acid sites was calculated from the pyridine adsorption using the Langmuir adsorption model. The Henry adsorption model was used in cases where no specific affinity between the adsorbent and the probe molecule was observed. The results were used to calculate the specific amounts of acidic and basic sites on SiO2- and TiO2-based materials. The zeta potential was measured for dip-coated TiO2 films, calcium- and phosphate-doped TiO2 films and for a non-bioactive Al2O3 film. Also, the calcium phosphate formation in simulated body fluid on in vitro bioactive TiO2 film was studied with zeta potential measurements. The results showed dependence on the negative surface charge and the important role of calcium adsorption in the beginning of the calcium phosphate formation. Surface topography of the films was investigated with atomic force microscopy, including a detailed analysis of the peak heights and distribution over cross sections. It was observed that in vitro bioactivity was strongly dependent on the nanoscale dimensions. Consequently, the in vitro calcium phosphate formation seems to be due to both the chemical interactions and the surface structure.

  13. Marine bioactives and potential application in sports.

    PubMed

    Gammone, Maria Alessandra; Gemello, Eugenio; Riccioni, Graziano; D'Orazio, Nicolantonio

    2014-04-30

    An enriched diet with antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP), such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-κB), macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS) production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports.

  14. Marine Bioactives and Potential Application in Sports

    PubMed Central

    Gammone, Maria Alessandra; Gemello, Eugenio; Riccioni, Graziano; D’Orazio, Nicolantonio

    2014-01-01

    An enriched diet with antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP), such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-κB), macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS) production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports. PMID:24796298

  15. Methods of Manufacturing Bioactive Gels from Extracellular Matrix Material

    NASA Technical Reports Server (NTRS)

    Kentner, Kimberly A. (Inventor); Stuart, Katherine A. (Inventor); Janis, Abram D. (Inventor)

    2014-01-01

    The present invention is directed to methods of manufacturing bioactive gels from ECM material, i.e., gels which retain bioactivity, and can serve as scaffolds for preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. The manufacturing methods take advantage of a new recognition that bioactive gels from ECM material can be created by digesting particularized ECM material in an alkaline environment and neutralizing to provide bioactive gels.

  16. Methods of Manufacturing Bioactive Gels from Extracellular Matrix Material

    NASA Technical Reports Server (NTRS)

    Kentner, Kimberly A. (Inventor); Stuart, Katherine A. (Inventor); Janis, Abram D. (Inventor)

    2015-01-01

    The present invention is directed to methods of manufacturing bioactive gels from ECM material, i.e., gels which retain bioactivity, and can serve as scaffolds for preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. The manufacturing methods take advantage of a new recognition that bioactive gels from ECM material can be created by digesting particularized ECM material in an alkaline environment and neutralizing to provide bioactive gels.

  17. Methods of Manufacturing Bioactive Gels from Extracellular Matrix Material

    NASA Technical Reports Server (NTRS)

    Kentner, Kimberly A. (Inventor); Stuart, Katherine A. (Inventor); Janis, Abram D. (Inventor)

    2016-01-01

    The present invention is directed to methods of manufacturing bioactive gels from ECM material, i.e., gels which retain bioactivity, and can serve as scaffolds for preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. The manufacturing methods take advantage of a new recognition that bioactive gels from ECM material can be created by digesting particularized ECM material in an alkaline environment and neutralizing to provide bioactive gels.

  18. Methods of Manufacturing Bioactive Gels from Extracellular Matrix Material

    NASA Technical Reports Server (NTRS)

    Kentner, Kimberly A. (Inventor); Stuart, Katherine A. (Inventor); Janis, Abram D. (Inventor)

    2016-01-01

    The present invention is directed to methods of manufacturing bioactive gels from ECM material, i.e., gels which retain bioactivity, and can serve as scaffolds for preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. The manufacturing methods take advantage of a new recognition that bioactive gels from ECM material can be created by digesting particularized ECM material in an alkaline environment and neutralizing to provide bioactive gels.

  19. Radio-opaque nanosized bioactive glass for potential root canal application: evaluation of radiopacity, bioactivity and alkaline capacity.

    PubMed

    Mohn, D; Zehnder, M; Imfeld, T; Stark, W J

    2010-03-01

    To produce novel nanosized bioactive glass particles with radio-opaque properties and high alkaline capacity and to evaluate their performance as a potential bioactive root canal dressing or filling material. Flame spray-derived bioactive glass particles in the nanometre range were produced including bismuth oxide as a radiopacifier. Calcium hydroxide, barium sulphate and bismuth oxide served as controls. Corresponding materials were compressed to obtain dense specimens with increased alkaline capacity. Radiopacity was evaluated, and in vitro bioactivity was monitored using Raman spectroscopy and scanning electron microscopy. Leaching of bismuth was controlled using atomic absorption spectroscopy. Bioactive glass particles with up to 50 wt% bismuth oxide revealed radiopacity with an equivalent of 4.94-mm aluminium. The introduction of bismuth into the bioactive glass altered the alkaline capacity and the in vitro bioactivity only for high bismuth oxide quantities. Bismuth oxide leaching out of the glass matrix was hardly detectable. Bioactive glass can be modified with bismuth oxide to become radio-opaque.

  20. Marine bioactive peptides as potential antioxidants.

    PubMed

    Ngo, Dai-Hung; Kim, Se-Kwon

    2013-05-01

    Bioactive peptides derived from marine organisms are the focus of current studies because of their numerous health beneficial effects. They exert various biological roles, one of the most crucial of which is the antioxidant effect. Reverse relationship between antioxidant intake and diseases has been approved through plenty of studies. Antioxidant activity of marine peptides can be attributed to in vitro and in vivo free radical scavenging activities. Antioxidant peptides isolated from marine sources may be used as functional ingredients in food formulations to promote consumer health and improve the shelf life of food products. This chapter presents an overview of the antioxidant peptides derived marine resources with the potential utilization in the food as well as pharmaceutical industries.

  1. Bioactive potential of Streptomyces against fish and shellfish pathogens

    PubMed Central

    Selvakumar, D; Arun, K; Suguna, S; Kumar, D; Dhevendaran, K

    2010-01-01

    Background and Objectives In the present study, isolation of Streptomyces associated with marine sponges and its bioactive potential against fish and shellfish pathogens were assessed. The Streptomyces sp. were isolated from the marine sponges namely Callyspongia diffusa, Mycale mytilorum, Tedania anhelans and Dysidea fragilis collected from Vizhinjam port, situated in the South-West coast of India. Materials and Methods The Streptomyces associated with marine sponges were isolated using specific ISP media. The isolates of Streptomyces were characterized for their colony characteristics, morphological properties, physiological and biochemical properties and were tentatively identified. The strains were cultivated on a lab scale level as shake-flask cultures and the crude extracts of the bioactive compounds obtained with ethyl acetate were screened biologically and chemically. By biological screening, the extracts were analyzed for their activity against fish and shellfish pathogens namely Aeromonas hydrophila, Serratia sp. and Vibrio spp, using the disk and agar-well diffusion bioassay method, while by chemical screening the crude culture extracts were analyzed by TLC and UV–Vis spectrophotometer. Results Ninety-four isolates were found to be associated with marine sponges, among them only seven strains showed antagonism against fish and shellfish pathogens. Analysis of morphological, physiological and biochemical characteristics suggested that these strains belonged to the genus Streptomyces. The initial screening of the isolates by spot inoculation method exhibited antibacterial activity against Aeromonas hydrophila. In-vitro screening of the submerge culture extracts showed positive inhibition against the fish and shellfish pathogens namely Aeromonas hydrophila, Serratia sp. and Vibrio spp. The screening of bioactive compounds confirmed the production of polyene substances by UV spectrum, which resulted in absorbance peaks ranging from 225 to 245 nm and TLC

  2. Planetary Interchange of Bioactive Material: Probability Factors and Implications

    NASA Astrophysics Data System (ADS)

    Clark, Benton C.

    2001-02-01

    It is now well-accepted that both lunar and martian materials are represented in the meteorite collections. Early suggestions that viable organisms might survive natural transport between planets have not yet been thoroughly examined. The concept of Planetary Interchange of Bioactive Material (PIBM) is potentially relevant to the conditions under which life originated. PIBM has been also invoked to infer that the potential danger to Earth from martian materials is non-existent, an inference with, however, many pitfalls. Numerous impediments to efficient transfer of viable organisms exist. In this work, the lethality of space radiation during long transients and the biasing of launched objects toward materials unlikely to host abundant organisms are examined and shown to reduce the likelihood of successful transfer by orders of magnitude. It is also shown that martian meteorites studied to date assuredly have been subjected to sterilizing levels of ionizing radiation in space. PIBM considerations apply to both the solar system locale(s) of the origin of life and to the applicability of planetary protection protocols to preserve the biospheres of planetary bodies, including our own.

  3. Interactions of bioactive glass materials in the oral environment

    NASA Astrophysics Data System (ADS)

    Efflandt, Sarah Elizabeth

    The aim of this research was to investigate bioactive glass materials for their use in dental restorations. Mechanical properties such as strength, toughness and wear resistance were considered initially, but the focus of this thesis was the biological properties such as reactions with saliva and interactions with natural dental tissues. Bioactive composite materials were created by incorporating bioactive glass and alumina powders into an aqueous suspension, slip casting, and infiltrating with resin. Microstructure, mechanical properties and wear resistance were evaluated. Mechanically, the composites are comparable to natural dental tissues and current dental materials with a strength of 206 +/- 18.7 MPa and a toughness of 1.74 +/- 0.08 MPa(m)1/2. Interfacial reactions were examined using bulk bioactive glasses. Disks were prepared from a melt, placed in saliva and incubated at 37°C. Surfaces were analyzed at 2, 5, 10, 21, and 42 days using scanning electron microscopy (SEM) and microdiffraction. Results showed changes at 2 days with apatite crystallization by 10 days. These glass disks were then secured against extracted human dentin and incubated in saliva for 21 or 42 days. Results from SEM, electron microprobe analysis (EMPA) and microdiffraction showed that dentin and bioactive glasses adhered in this in vitro environment due to attraction of collagen to bioactive glasses and growth of an interfacial apatite. After investigating these bulk glass responses, particulate bioactive glasses were placed in in vitro and in vivo set-ups for evaluation. Particles immersed in biologically buffered saliva showed crystallization of apatite at 3 days. These bioactive glass particles were placed in the molars of mini-pigs and left in vivo. After 30 days the bioactive paste was evaluated using SEM, EMPA and microdiffraction analyses. Results showed that the paste gained structural integrity and had chemical changes in vivo. These sets of experiments show that bioactive

  4. Littoral lichens as a novel source of potentially bioactive Actinobacteria.

    PubMed

    Parrot, Delphine; Antony-Babu, Sanjay; Intertaglia, Laurent; Grube, Martin; Tomasi, Sophie; Suzuki, Marcelino T

    2015-10-30

    Cultivable Actinobacteria are the largest source of microbially derived bioactive molecules. The high demand for novel antibiotics highlights the need for exploring novel sources of these bacteria. Microbial symbioses with sessile macro-organisms, known to contain bioactive compounds likely of bacterial origin, represent an interesting and underexplored source of Actinobacteria. We studied the diversity and potential for bioactive-metabolite production of Actinobacteria associated with two marine lichens (Lichina confinis and L. pygmaea; from intertidal and subtidal zones) and one littoral lichen (Roccella fuciformis; from supratidal zone) from the Brittany coast (France), as well as the terrestrial lichen Collema auriforme (from a riparian zone, Austria). A total of 247 bacterial strains were isolated using two selective media. Isolates were identified and clustered into 101 OTUs (98% identity) including 51 actinobacterial OTUs. The actinobacterial families observed were: Brevibacteriaceae, Cellulomonadaceae, Gordoniaceae, Micrococcaceae, Mycobacteriaceae, Nocardioidaceae, Promicromonosporaceae, Pseudonocardiaceae, Sanguibacteraceae and Streptomycetaceae. Interestingly, the diversity was most influenced by the selective media rather than lichen species or the level of lichen thallus association. The potential for bioactive-metabolite biosynthesis of the isolates was confirmed by screening genes coding for polyketide synthases types I and II. These results show that littoral lichens are a source of diverse potentially bioactive Actinobacteria.

  5. Littoral lichens as a novel source of potentially bioactive Actinobacteria

    PubMed Central

    Parrot, Delphine; Antony-Babu, Sanjay; Intertaglia, Laurent; Grube, Martin; Tomasi, Sophie; Suzuki, Marcelino T.

    2015-01-01

    Cultivable Actinobacteria are the largest source of microbially derived bioactive molecules. The high demand for novel antibiotics highlights the need for exploring novel sources of these bacteria. Microbial symbioses with sessile macro-organisms, known to contain bioactive compounds likely of bacterial origin, represent an interesting and underexplored source of Actinobacteria. We studied the diversity and potential for bioactive-metabolite production of Actinobacteria associated with two marine lichens (Lichina confinis and L. pygmaea; from intertidal and subtidal zones) and one littoral lichen (Roccella fuciformis; from supratidal zone) from the Brittany coast (France), as well as the terrestrial lichen Collema auriforme (from a riparian zone, Austria). A total of 247 bacterial strains were isolated using two selective media. Isolates were identified and clustered into 101 OTUs (98% identity) including 51 actinobacterial OTUs. The actinobacterial families observed were: Brevibacteriaceae, Cellulomonadaceae, Gordoniaceae, Micrococcaceae, Mycobacteriaceae, Nocardioidaceae, Promicromonosporaceae, Pseudonocardiaceae, Sanguibacteraceae and Streptomycetaceae. Interestingly, the diversity was most influenced by the selective media rather than lichen species or the level of lichen thallus association. The potential for bioactive-metabolite biosynthesis of the isolates was confirmed by screening genes coding for polyketide synthases types I and II. These results show that littoral lichens are a source of diverse potentially bioactive Actinobacteria. PMID:26514347

  6. High-pressure processing as emergent technology for the extraction of bioactive ingredients from plant materials.

    PubMed

    Jun, Xi

    2013-01-01

    High-pressure processing is a food processing technique that has shown great potentials in the food industry. Recently, it was developed to extract bioactive ingredients from plant materials, known as ultrahigh pressure extraction (UPE), taking advantages of time saving, higher extraction yields, fewer impurities in the extraction solution, minimal heat and can avoid thermal degradation on the activity and structure of bioactive components, and so on. This review provides an overview of the developments in the UPE of bioactive ingredients from plant material. Apart from a brief presentation of the theories of UPE and extraction equipment systems, the principal parameters that influence the extraction efficiency to be optimized in the UPE (e.g., solvent, pressure, temperature, extraction time, and the number of cycle) were discussed in detail, and finally the more recent applications of UPE for the extraction of active compounds from plant materials were summarized.

  7. Microgel particles for the delivery of bioactive materials

    SciTech Connect

    Frechet, Jean M. J.; Murthy Niren

    2010-03-23

    Novel microgels, microparticles and related polymeric materials capable of delivering bioactive materials to cells for use as vaccines or therapeutic agents. The materials are made using a crosslinker molecule that contains a linkage cleavable under mild acidic conditions. The crosslinker molecule is exemplified by a bisacryloyl acetal crosslinker. The new materials have the common characteristic of being able to degrade by acid hydrolysis under conditions commonly found within the endosomal or lysosomal compartments of cells thereby releasing their payload within the cell. The materials can also be used for the delivery of therapeutics to the acidic regions of tumors and sites of inflammation.

  8. Microgel particles for the delivery of bioactive materials

    DOEpatents

    Frechet, Jean M.; Murthy, Niren

    2006-06-06

    Novel microgels, microparticles and related polymeric materials capable of delivering bioactive materials to cells for use as vaccines or therapeutic agents. The materials are made using a crosslinker molecule that contains a linkage cleavable under mild acidic conditions. The crosslinker molecule is exemplified by a bisacryloyl acetal crosslinker. The new materials have the common characteristic of being able to degrade by acid hydrolysis under conditions commonly found within the endosomal or lysosomal compartments of cells thereby releasing their payload within the cell. The materials can also be used for the delivery of therapeutics to the acidic regions of tumors and sites of inflammation.

  9. Potential of fruit wastes as natural resources of bioactive compounds.

    PubMed

    Deng, Gui-Fang; Shen, Chen; Xu, Xiang-Rong; Kuang, Ru-Dan; Guo, Ya-Jun; Zeng, Li-Shan; Gao, Li-Li; Lin, Xi; Xie, Jie-Feng; Xia, En-Qin; Li, Sha; Wu, Shan; Chen, Feng; Ling, Wen-Hua; Li, Hua-Bin

    2012-01-01

    Fruit wastes are one of the main sources of municipal waste. In order to explore the potential of fruit wastes as natural resources of bioactive compounds, the antioxidant potency and total phenolic contents (TPC) of lipophilic and hydrophilic components in wastes (peel and seed) of 50 fruits were systematically evaluated. The results showed that different fruit residues had diverse antioxidant potency and the variation was very large. Furthermore, the main bioactive compounds were identified and quantified, and catechin, cyanidin 3-glucoside, epicatechin, galangin, gallic acid, homogentisic acid, kaempferol, and chlorogenic acid were widely found in these residues. Especially, the values of ferric-reducing antioxidant power (FRAP), trolox equivalent antioxidant capacity (TEAC) and TPC in the residues were higher than in pulps. The results showed that fruit residues could be inexpensive and readily available resources of bioactive compounds for use in the food and pharmaceutical industries.

  10. The chemotherapeutic potential of Terminalia ferdinandiana: Phytochemistry and bioactivity

    PubMed Central

    Mohanty, S.; Cock, Ian E.

    2012-01-01

    Plants contain a myriad of natural compounds which exhibit important bioactive properties. These compounds may provide alternatives to current medications and afford a significant avenue for new drug discovery. Despite this, little information is available in the literature regarding native Australian plants and their potential for medicinal and industrial uses. Recent studies have reported Terminalia ferdinandiana to be an extremely good source of antioxidants. Indeed, T. ferdinandiana has been reported to have ascorbic acid levels per gram of fruit more than 900 times higher than blueberries. T. ferdinandiana also has high levels of a variety of other antioxidants, including phenolic compounds and anthocyanins. Antioxidants have been associated with the prevention of cancer, cardiovascular diseases, and neurological degenerative disorders. They are also linked with antidiabetic bioactivities and have been associated with the reduction of obesity. Antioxidants can directly scavenge free radicals, protecting cells against oxidative stress-related damage to proteins, lipids, and nucleic acids. Therefore, T. ferdinandiana has potential in the treatment of a variety of diseases and disorders and its potential bioactivities warrant further investigation. PMID:22654402

  11. Self assembling bioactive materials for cell adhesion in tissue repair

    NASA Astrophysics Data System (ADS)

    Hwang, Julia J.

    This work involved the study of biodegradable and biocompatible materials that have the potential to modify tissue engineering scaffolds through self assembly, generating multiple layers that deliver bioactivity. Diblock biomaterials containing cholesteryl moieties and oligomers of lactic acid units were found to form single crystals when precipitated from hot ethanol and smectic liquid crystalline phases when cast as a film. Cell culture experiments on these films with 3T3 and 3T6 fibroblasts indicated that these ordered materials form surfaces with specific chemistries that favored cell adhesion, spreading, and proliferation suggesting the potential of mediating human tissue repair. The author believes the cholesteryl moieties found on the surface play a key role in determining cell behavior. Cholesteryl-(L-lactic acid) diblock molecules were then functionalized with moieties including vitamin Bx, cholesterol, and the anti-inflammatory drug indomethacin. An unstable activated ester between indomethacin and the diblock molecule resulted in the release of indomethacin into the culture medium which inhibited the proliferation of 3T3 fibroblasts. Finally, a series of molecules were designed to incorporate dendrons based on amino acids at the termini of the diblock structures. It was determined that lysine, a basic amino acid, covalently coupled to cholesteryl-(L-lactic acid) can promote cell adhesion and spreading while negatively charged and zwitterionic 2nd generation dendrons based on aspartic acid do not. Incorporation of the well known arginine-glycine-aspartic acid (RGD) sequence, which is found in many adhesive proteins, to the dendrons imparted integrin-mediated cell adhesion as evidenced by the formation of stress fibers. We also explored the capacity of integrin receptors to bind to ligands that are not the linear form of RGD, but have R, G, and D spatially positioned to mimic the linear RGD environments. For this purpose, the arms of the 2 nd generation

  12. Bioactive glass-based materials with hierarchical porosity for medical applications: Review of recent advances.

    PubMed

    Baino, Francesco; Fiorilli, Sonia; Vitale-Brovarone, Chiara

    2016-09-15

    Bioactive glasses have been traditionally used in the clinical practice to fill and restore osseous defects due to their unique ability to bond to host bone and stimulate new bone growth. In the last decade, a new set of bioactive glasses characterized by a highly ordered mesoporous texture has been developed and studied as a smart platform for the controlled release of biomolecules, in situ therapy and regenerative applications. This review points out the great potential carried by hierarchical bioactive glass scaffolds that exhibit pore scales from the meso- to the macro-range, and their impact in the broad field of tissue engineering, including the emerging applications in contact with soft tissues and diagnostics. Recent advances in the preparation methods of these multiscale constructs (e.g. mono- or multi-phase scaffolds, fibrous meshes, coated systems, porous nanospheres, and composites) are examined, along with their strengths and weaknesses. A bright future is expected for hierarchical systems based on biocompatible mesoporous materials as they can provide a unique set of functionalities, including enhanced bioactivity, local release of ions and drugs to elicit specific therapeutic effects (improved osteogenesis and angiogenesis, antibacterial properties), and implant/drug tracking, which were unthinkable when research on bioactive glasses began. The advent of mesoporous bioactive glasses led to the birth of a new class of multifunctional biomaterials that have been proposed as smart platforms for local drug release and bone regeneration. Furthermore, mesoporous materials have been recently employed in the development of hierarchical macro-mesoporous scaffolds, composites and implantable systems. This reviews summarizes the latest applications of these multiscale biomaterials in tissue engineering, including the emerging applications in contact with soft tissues and diagnostics. The preparation methods, current uses and potential of these constructs and

  13. Development of bioactive materials using reticulated ceramics for bone substitute

    NASA Astrophysics Data System (ADS)

    Jiang, Gengwei

    For hard tissue prosthetics, it is necessary to seek novel synthesis routes by which a real structural bone can be simulated in terms of bioactivity, porosity, and mechanical behavior. The work presented here deals with the development of such a component by a novel synthesis route for bone implantation. To enhance the mechanical properties, an industrial alumina has been selected as the substrate. Alumina is not only bio inert but also mechanically strong which makes it an ideal substrate for bone substitute. The high porosity is achieved via a sponge technique by which both pore size and density can be changed easily. The bioactivity is induced by coating a highly bioactive HA film onto the inner pore surfaces of the reticulated alumina. Based on this concept, the research has focused on the coating of HA onto inner pore surfaces of the reticulated alumina via several effective methods that are developed in our laboratory. No previous studies have so far been reported on coating inner surfaces of small-diameter pores ranging from 0.1--1.0 mm. The key materials processing issues dealt with in this work include precursor chemistry, coating procedures, synthesis of coated component, interface structure study, film adhesion strength testing, and mechanical properties of the component. This novel approach has shown great promise in synthesizing bone substitutes. To determine the applicability of the coated component in hard tissue prosthetics, a bioactivity study has been carried out. By immersing the synthetic HA into simulated body fluid (SBF), the bioresponse has been measured for a variety of samples with different processing conditions. Fundamental aspects of this study are centered on the effects of structural characteristics of HA on the bioactivity. Based on extensive IR and XRD experimental data, it has been found that the bioactivity of HA is sensitively controlled by the structural crystallinity of the HA and its specific surface area. Furthermore, based on

  14. Bioactive compounds and antioxidant potential fruit of Ximenia americana L.

    PubMed

    Almeida, Maria Lucilania Bezerra; Freitas, Wallace Edelky de Souza; de Morais, Patrícia Lígia Dantas; Sarmento, José Dárcio Abrantes; Alves, Ricardo Elesbão

    2016-02-01

    The caatinga ecoregion in northeast Brazil presents a wide variety in plant species. However, the potential of these species as a source of energy, carbohydrates, vitamins, minerals and bioactive properties beneficial to health is still unknown. Among these species we can find the wild plum (Ximenia americana). Due to its various phytotherapeutic properties and absence of studies on the chemical composition of the fruit this article aimed to evaluate the bioactive compounds and antioxidant potential of the X. americana in different stages of maturation. The fruits of X. americana showed considerable amounts of bioactive compounds, as well as antioxidant activity and antioxidant enzymes. The fruits at green maturity stage showed higher content of yellow flavonoids (22.07 mg/100g), anthocyanins (1.92 mg/100 g), polyphenols (3051.62 mg/100 g), starch (4.22%), antioxidant activity (489.40 g fruit/g DPPH and 198.77 μmol Trolox/g) and activity of antioxidant enzymes; the antioxidant activity allocated to the fruit was shown to be related to the contents of extractable polyphenols, yellow flavonoids, total anthocyanins and antioxidant enzymes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Marine bioactives: pharmacological properties and potential applications against inflammatory diseases.

    PubMed

    D'Orazio, Nicolantonio; Gammone, Maria Alessandra; Gemello, Eugenio; De Girolamo, Massimo; Cusenza, Salvatore; Riccioni, Graziano

    2012-04-01

    Inflammation is a hot topic in medical research, because it plays a key role in inflammatory diseases: rheumatoid arthritis (RA) and other forms of arthritis, diabetes, heart diseases, irritable bowel syndrome, Alzheimer's disease, Parkinson's disease, allergies, asthma, even cancer and many others. Over the past few decades, it was realized that the process of inflammation is virtually the same in different disorders, and a better understanding of inflammation may lead to better treatments for numerous diseases. Inflammation is the activation of the immune system in response to infection, irritation, or injury, with an influx of white blood cells, redness, heat, swelling, pain, and dysfunction of the organs involved. Although the pathophysiological basis of these conditions is not yet fully understood, reactive oxygen species (ROS) have often been implicated in their pathogenesis. In fact, in inflammatory diseases the antioxidant defense system is compromised, as evidenced by increased markers of oxidative stress, and decreased levels of protective antioxidant enzymes in patients with rheumatoid arthritis (RA). An enriched diet containing antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic substances, has been suggested to improve symptoms by reducing disease-related oxidative stress. In this respect, the marine world represents a largely untapped reserve of bioactive ingredients, and considerable potential exists for exploitation of these bioactives as functional food ingredients. Substances such as n-3 oils, carotenoids, vitamins, minerals and peptides provide a myriad of health benefits, including reduction of cardiovascular diseases, anticarcinogenic and anti-inflammatory activities. New marine bioactives are recently gaining attention, since they could be helpful in combating chronic inflammatory degenerative conditions. The aim of this review is to examine the published studies concerning the potential pharmacological properties and

  16. Marine Bioactives: Pharmacological Properties and Potential Applications against Inflammatory Diseases

    PubMed Central

    D’Orazio, Nicolantonio; Gammone, Maria Alessandra; Gemello, Eugenio; De Girolamo, Massimo; Cusenza, Salvatore; Riccioni, Graziano

    2012-01-01

    Inflammation is a hot topic in medical research, because it plays a key role in inflammatory diseases: rheumatoid arthritis (RA) and other forms of arthritis, diabetes, heart diseases, irritable bowel syndrome, Alzheimer’s disease, Parkinson’s disease, allergies, asthma, even cancer and many others. Over the past few decades, it was realized that the process of inflammation is virtually the same in different disorders, and a better understanding of inflammation may lead to better treatments for numerous diseases. Inflammation is the activation of the immune system in response to infection, irritation, or injury, with an influx of white blood cells, redness, heat, swelling, pain, and dysfunction of the organs involved. Although the pathophysiological basis of these conditions is not yet fully understood, reactive oxygen species (ROS) have often been implicated in their pathogenesis. In fact, in inflammatory diseases the antioxidant defense system is compromised, as evidenced by increased markers of oxidative stress, and decreased levels of protective antioxidant enzymes in patients with rheumatoid arthritis (RA). An enriched diet containing antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic substances, has been suggested to improve symptoms by reducing disease-related oxidative stress. In this respect, the marine world represents a largely untapped reserve of bioactive ingredients, and considerable potential exists for exploitation of these bioactives as functional food ingredients. Substances such as n-3 oils, carotenoids, vitamins, minerals and peptides provide a myriad of health benefits, including reduction of cardiovascular diseases, anticarcinogenic and anti-inflammatory activities. New marine bioactives are recently gaining attention, since they could be helpful in combating chronic inflammatory degenerative conditions. The aim of this review is to examine the published studies concerning the potential pharmacological properties and

  17. Stem cell homing-based tissue engineering using bioactive materials

    NASA Astrophysics Data System (ADS)

    Yu, Yinxian; Sun, Binbin; Yi, Chengqing; Mo, Xiumei

    2017-06-01

    Tissue engineering focuses on repairing tissue and restoring tissue functions by employing three elements: scaffolds, cells and biochemical signals. In tissue engineering, bioactive material scaffolds have been used to cure tissue and organ defects with stem cell-based therapies being one of the best documented approaches. In the review, different biomaterials which are used in several methods to fabricate tissue engineering scaffolds were explained and show good properties (biocompatibility, biodegradability, and mechanical properties etc.) for cell migration and infiltration. Stem cell homing is a recruitment process for inducing the migration of the systemically transplanted cells, or host cells, to defect sites. The mechanisms and modes of stem cell homing-based tissue engineering can be divided into two types depending on the source of the stem cells: endogenous and exogenous. Exogenous stem cell-based bioactive scaffolds have the challenge of long-term culturing in vitro and for endogenous stem cells the biochemical signal homing recruitment mechanism is not clear yet. Although the stem cell homing-based bioactive scaffolds are attractive candidates for tissue defect therapies, based on in vitro studies and animal tests, there is still a long way before clinical application.

  18. Development of implants composed of bioactive materials for bone repair

    NASA Astrophysics Data System (ADS)

    Xiao, Wei

    The purpose of this Ph.D. research was to address the clinical need for synthetic bioactive materials to heal defects in non-loaded and loaded bone. Hollow hydroxyapatite (HA) microspheres created in a previous study were evaluated as a carrier for controlled release of bone morphogenetic protein-2 (BMP2) in bone regeneration. New bone formation in rat calvarial defects implanted with BMP2-loaded microspheres (43%) was significantly higher than microspheres without BMP2 (17%) at 6 weeks postimplantation. Then hollow HA microspheres with a carbonate-substituted composition were prepared to improve their resorption rate. Hollow HA microspheres with 12 wt. % of carbonate showed significantly higher new bone formation (73 +/- 8%) and lower residual HA (7 +/- 2%) than stoichiometric HA microspheres (59 +/- 2% new bone formation; 21 +/- 3% residual HA). The combination of carbonate-substituted hollow HA microspheres and clinically-safe doses of BMP2 could provide promising implants for healing non-loaded bone defects. Strong porous scaffolds of bioactive silicate (13-93) glass were designed with the aid of finite-element modeling, created by robocasting and evaluated for loaded bone repair. Scaffolds with a porosity gradient to mimic human cortical bone showed a compressive strength of 88 +/- 20 MPa, a flexural strength of 34 +/- 5 MPa and the ability to support bone infiltration in vivo. The addition of a biodegradable polylactic acid (PLA) layer to the external surface of these scaffolds increased their load-bearing capacity in four-point bending by 50% and dramatically enhanced their work of fracture, resulting in a "ductile" mechanical response. These bioactive glass-PLA composites, combining bioactivity, high strength, high work of fracture and an internal architecture conducive to bone infiltration, could provide optimal implants for structural bone repair.

  19. Alkali and heat treatment of titanium implant material for bioactivity.

    PubMed

    Hamouda, Ibrahim M; Enan, Enas T; Al-Wakeel, Essam E; Yousef, Mostafa K M

    2012-01-01

    This study was conducted to evaluate alkali- and heat-treated titanium implant material. Ninety-eight square plates of commercially pure titanium were divided into three groups. Group 1 plates were left untreated, and groups 2 and 3 were subjected to anodization and alkali treatment for 24 and 48 hours, respectively. Treated specimens were then subdivided into three equal subgroups (a, b, and c), which were heat treated for 1 hour at temperatures of 500°C, 700°C, and 800°C, respectively. Changes in the crystalline structure were analyzed using x-ray diffractometry. Surface roughness was measured using a surface roughness tester. Selected specimens were immersed in a specially prepared simulated body fluid for 10 days. Calcium and phosphorous deposition on the specimens was detected using energy dispersive x-ray analysis. Increasing the alkali treatment period and heat treatment temperature positively affected surface roughness and formation of a bioactive sodium titanium oxide (sodium titanate) layer on the titanium surface, especially after heat treatment at 800°C. There was a significantly higher calcium deposition on specimens of group 3 in comparison with those of groups 1 and 2. The results of pH and ion concentration changes of the used simulated body fluid confirmed the results of energy dispersive x-ray analysis. Alkali and heat treatment of titanium implant materials created better treatment conditions for obtaining a bioactive implant material.

  20. Direct pulp capping in an immature incisor using a new bioactive material

    PubMed Central

    Bhat, Sham S.; Hegde, Sundeep K.; Adhikari, Fardin; Bhat, Vidya S.

    2014-01-01

    Preservation of the pulp in a traumatized immature fractured incisor tooth is of prime importance in order to achieve apexogenesis, a natural apical closure. The main factor influencing this is pulpal protection by a bioactive material proving optimum marginal seal in preventing any microleakage. This case report presents an 8-year-old female diagnosed with Ellis Class 3 fracture of immature tooth 11 involving the mesial pulp horn. Under rubber dam isolation, a partial pulpotomy was performed and the pulp was sealed using a new bioactive material BIODENTINE to stimulate apexogenesis, dentine replacement and pulp protection. The fractured segment was reattached for optimum esthetics, which was a concern for the patient. The patient was followed-up for 1, 3, 6 and 12 months, which revealed continued apical closure and maintenance of pulp vitality. The patient remained asymptomatic. This case report provides evidence for the potential use of Biodentine as an effective pulp capping material in the future. PMID:25191081

  1. Bioactive ceramic-based materials with designed reactivity for bone tissue regeneration

    PubMed Central

    Ohtsuki, Chikara; Kamitakahara, Masanobu; Miyazaki, Toshiki

    2009-01-01

    Bioactive ceramics have been used clinically to repair bone defects owing to their biological affinity to living bone; i.e. the capability of direct bonding to living bone, their so-called bioactivity. However, currently available bioactive ceramics do not satisfy every clinical application. Therefore, the development of novel design of bioactive materials is necessary. Bioactive ceramics show osteoconduction by formation of biologically active bone-like apatite through chemical reaction of the ceramic surface with surrounding body fluid. Hence, the control of their chemical reactivity in body fluid is essential to developing novel bioactive materials as well as biodegradable materials. This paper reviews novel bioactive materials designed based on chemical reactivity in body fluid. PMID:19158015

  2. The use of bioactive peptides to modify materials for bone tissue repair.

    PubMed

    Wang, Cunyang; Liu, Yan; Fan, Yubo; Li, Xiaoming

    2017-06-01

    It has been well recognized that the modification of biomaterials with appropriate bioactive peptides could further enhance their functions. Especially, it has been shown that peptide-modified bone repair materials could promote new bone formation more efficiently compared with conventional ones. The purpose of this article is to give a general review of recent studies on bioactive peptide-modified materials for bone tissue repair. Firstly, the main peptides for inducing bone regeneration and commonly used methods to prepare peptide-modified bone repair materials are introduced. Then, current in vitro and in vivo research progress of peptide-modified composites used as potential bone repair materials are reviewed and discussed. Generally speaking, the recent related studies have fully suggested that the modification of bone repair materials with osteogenic-related peptides provide promising strategies for the development of bioactive materials and substrates for enhanced bone regeneration and the therapy of bone tissue diseases. Furthermore, we have proposed some research trends in the conclusion and perspectives part.

  3. The use of bioactive peptides to modify materials for bone tissue repair

    PubMed Central

    Wang, Cunyang; Liu, Yan; Fan, Yubo

    2017-01-01

    Abstract It has been well recognized that the modification of biomaterials with appropriate bioactive peptides could further enhance their functions. Especially, it has been shown that peptide-modified bone repair materials could promote new bone formation more efficiently compared with conventional ones. The purpose of this article is to give a general review of recent studies on bioactive peptide-modified materials for bone tissue repair. Firstly, the main peptides for inducing bone regeneration and commonly used methods to prepare peptide-modified bone repair materials are introduced. Then, current in vitro and in vivo research progress of peptide-modified composites used as potential bone repair materials are reviewed and discussed. Generally speaking, the recent related studies have fully suggested that the modification of bone repair materials with osteogenic-related peptides provide promising strategies for the development of bioactive materials and substrates for enhanced bone regeneration and the therapy of bone tissue diseases. Furthermore, we have proposed some research trends in the conclusion and perspectives part. PMID:28596916

  4. The major bioactive components of seaweeds and their mosquitocidal potential.

    PubMed

    Yu, Ke-Xin; Jantan, Ibrahim; Ahmad, Rohani; Wong, Ching-Lee

    2014-09-01

    Seaweeds are one of the most widely studied natural resources for their biological activities. Novel seaweed compounds with unique chemical structures have been reported for their pharmacological properties. The urge to search for novel insecticidal compound with a new mode of action for development of botanical insecticides supports the relevant scientific research on discovering the bioactive compounds in seaweeds. The mosquitocidal potential of seaweed extracts and their isolated compounds are documented in this review paper, along with the discussion on bioactivities of the major components of seaweeds such as polysaccharides, phenolics, proteins, terpenes, lipids, and halogenated compounds. The effects of seaweed extracts and compounds toward different life stages of mosquito (egg, larva, pupa, and adult), its growth, development, and reproduction are elaborated. The structure-activity relationships of mosquitocidal compounds are discussed to extrapolate the possible chemical characteristics of seaweed compounds responsible for insecticidal properties. Furthermore, the possible target sites and mode of actions of the mosquitocidal seaweed compounds are included in this paper. The potential synergistic effects between seaweeds and commercial insecticides as well as the toxic effects of seaweed extracts and compounds toward other insects and non-target organisms in the same habitat are also described. On top of that, various factors that influence the mosquitocidal potential of seaweeds, such as abiotic and biotic variables, sample preparation, test procedures, and considerations for a precise experimental design are discussed. The potential of active seaweed extracts and compounds in the development of effective bioinsecticide are also discussed.

  5. Bioprospecting potential of the soil metagenome: novel enzymes and bioactivities.

    PubMed

    Lee, Myung Hwan; Lee, Seon-Woo

    2013-09-01

    The microbial diversity in soil ecosystems is higher than in any other microbial ecosystem. The majority of soil microorganisms has not been characterized, because the dominant members have not been readily culturable on standard cultivation media; therefore, the soil ecosystem is a great reservoir for the discovery of novel microbial enzymes and bioactivities. The soil metagenome, the collective microbial genome, could be cloned and sequenced directly from soils to search for novel microbial resources. This review summarizes the microbial diversity in soils and the efforts to search for microbial resources from the soil metagenome, with more emphasis on the potential of bioprospecting metagenomics and recent discoveries.

  6. From flab to fab: transforming surgical waste into an effective bioactive coating material.

    PubMed

    Luo, Baiwen; Yuan, Shaojun; Foo, Selin Ee Min; Wong, Marcus Thien Chong; Lim, Thiam Chye; Tan, Nguan Soon; Choong, Cleo

    2015-03-11

    Cellular events are regulated by the interaction between integrin receptors in the cell membrane and the extracellular matrix (ECM). Hence, ECM, as a material, can potentially play an instructive role in cell-material interactions. Currently, adipose tissue in the form of lipoaspirate is often discarded. Here, it is demonstrated how our chemical-free decellularization method could be used to obtain ECM from human lipoaspirate waste material. These investigations show that the main biological components are retained in the lipoaspirate-derived ECM (LpECM) material and that this LpECM material could subsequently be used as a coating material to confer bioactivity to an otherwise inert biodegradable material (i.e., polycaprolactone). Overall, lipoaspirate material, a complex blend of endogenous proteins, is effectively used a bioactive coating material. This work is an important stepping-stone towards the development of biohybrid scaffolds that contain cellular benefits without requiring the use of additional biologics based on commonly discarded lipoaspirate material. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Bioactive Glass Nanoparticles: From Synthesis to Materials Design for Biomedical Applications.

    PubMed

    Vichery, Charlotte; Nedelec, Jean-Marie

    2016-04-14

    Thanks to their high biocompatibility and bioactivity, bioactive glasses are very promising materials for soft and hard tissue repair and engineering. Because bioactivity and specific surface area intrinsically linked, the last decade has seen a focus on the development of highly porous and/or nano-sized materials. This review emphasizes the synthesis of bioactive glass nanoparticles and materials design strategies. The first part comprehensively covers mainly soft chemistry processes, which aim to obtain dispersible and monodispersed nanoparticles. The second part discusses the use of bioactive glass nanoparticles for medical applications, highlighting the design of materials. Mesoporous nanoparticles for drug delivery, injectable systems and scaffolds consisting of bioactive glass nanoparticles dispersed in a polymer, implant coatings and particle dispersions will be presented.

  8. Magnetoelastic materials as novel bioactive coatings for the control of cell adhesion.

    PubMed

    Vlaisavljevich, Eli; Janka, Logan P; Ong, Keat Ghee; Rajachar, Rupak M

    2011-03-01

    Interfacial fibrosis is known to dramatically decrease the lifespan, stability, and function of biomedical implants and bone-anchored prosthetics. Bioactive coatings aimed at mitigating fibrous adhesions are one of the approaches to alleviate the problem. In this paper, we are developing a bioactive coating based upon a magnetoelastic (ME) material that vibrates in response to an ac magnetic field. In order to establish these coatings for this purpose, the ME material was first rendered bioactive through the sequential addition of polyurethane and chitosan thin films. Indirect live/dead assays were performed showing increased cell viability for polyurethane and chitosan-coated sensors compared to the uncoated controls. Direct adhesion experiments were performed to test the response of fibroblasts cultured on static and vibrated ME materials. Results showed cells adherent to static but not vibrated coatings. Detached cells showed no viability loss compared to controls. The finding that submicrometer ME vibrations can prevent cell adhesion in vitro without inducing cell death suggests the potential of these coatings to effectively control interfacial fibrosis. Future work will address the effect of vibrations on cell morphology and local gene expression in vitro, as well as fibrous tissue formation in vivo.

  9. Bioactivities of alternative protein sources and their potential health benefits.

    PubMed

    Pihlanto, A; Mattila, P; Mäkinen, S; Pajari, A-M

    2017-08-14

    Increasing the utilisation of plant proteins is needed to support the production of protein-rich foods that could replace animal proteins in the human diet so as to reduce the strain that intensive animal husbandry poses to the environment. Lupins, quinoa and hempseed are significant sources of energy, high quality proteins, fibre, vitamins and minerals. In addition, they contain compounds such as polyphenols and bioactive peptides that can increase the nutritional value of these plants. From the nutritional standpoint, the right combination of plant proteins can supply sufficient amounts of essential amino acids for human requirements. This review aims at providing an overview of the current knowledge of the nutritional properties, beneficial and non-nutritive compounds, storage proteins, and potential health benefits of lupins, quinoa and hempseed.

  10. Marine fish-derived bioactive peptides as potential antihypertensive agents.

    PubMed

    Kim, Se-Kwon; Ngo, Dai-Hung; Vo, Thanh-Sang

    2012-01-01

    Hypertension is the most widespread risk factor for many serious cardiovascular diseases. Angiotensin-converting enzyme (ACE) plays a crucial role in cardiovascular physiological regulation by converting angiotensin I to a potent vasoconstrictor, angiotensin II. Hence, the inhibition of ACE is a key target for antihypertensive activity. Recently, potent antihypertensive peptides have been purified widely by enzymatic hydrolysis of muscle protein, skin collagen, and gelatin of many different kinds of marine fishes. Marine fish-derived bioactive peptides can be developed as antihypertensive components in functional foods or nutraceuticals. This contribution presents an overview of the ACE inhibitory peptides derived from marine fishes and discusses their future prospects to be used as potential drug candidates for preventing and treating high blood pressure. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Bone response to porous alumina implants coated with bioactive materials, observed using different characterization techniques.

    PubMed

    Camilo, Claudia C; Silveira, Celey A E; Faeda, Rafael S; de Almeida Rollo, João M D; Purquerio, Benedito de Moraes; Fortulan, Carlos Alberto

    2017-07-27

    Implants or implantable devices should integrate into the host tissue faster than fibrous capsule formation, in which the design of the interface is one of the biggest challenges. Generally, bioactive materials are not viable for load-bearing applications, so inert biomaterials are proposed. However, the surface must be modified through techniques such as coating with bioactive materials, roughness and sized pores. The aim of this research was to validate an approach for the evaluation of the tissue growth on implants of porous alumina coated with bioactive materials. Porous alumina implants were coated with 45S5 Bioglass® (BG) and hydroxyapatite (HA) and implanted in rat tibiae for a period of 28 days. Ex vivo resections were performed to analyze osseointegration, along with histological analysis, Scanning Electron Microscopy with Energy Dispersive X-Ray spectroscopy (SEM-EDX) line scanning, radiography and biomechanical testing. Given that the process of implant integration needs with the bone tissue to be accelerated, it was then seen that BG acted to start the rapid integration, and HA acted to sustaining the process. Inert materials coated with bioglass and HA present a potential for application as bone substitutes, preferably with pores of diameters between 100 μm and 400 μm and, restrict for smaller than 100 μm, because it prevents pores without organized tissue formation or vacant. Designed as functional gradient material, stand out for applications in bone tissue under load, where, being the porous surface responsible for the osseointegration and the inner material to bear and to transmit the loads.

  12. [Preparation and characteristics of aerogel-based bioactive materials used in dentistry].

    PubMed

    Lázár, István; Kuttor, Andrea; Győri, Enikö; Veres, Péter; Fábián, István; Manó, Sándor; Hegedüs, Csaba

    2015-03-01

    A variety of bioactive materials have been investigated as substitute materials for diseased or damaged bone tissues in dentistry. The aim of this study was to prepare mesoporous silica containing biomaterials by sol-gel technology. These materials may be combinated with hydroxyapatite and β-tricalcium phosphate, as bioactive agents. The synthesis and testing of important physical parameters were performed. Based on these measurements, the silica aerogel can be an applicable material in the dental field in the future.

  13. Atmospheric-Pressure Cold Plasmas Used to Embed Bioactive Compounds in Matrix Material for Active Packaging of Fruits and Vegetables

    NASA Astrophysics Data System (ADS)

    Fernandez, Sulmer; Pedrow, Patrick; Powers, Joseph; Pitts, Marvin

    2009-10-01

    Active thin film packaging is a technology with the potential to provide consumers with new fruit and vegetable products-if the film can be applied without deactivating bioactive compounds.Atmospheric pressure cold plasma (APCP) processing can be used to activate monomer with concomitant deposition of an organic plasma polymerized matrix material and to immobilize a bioactive compound all at or below room temperature.Aims of this work include: 1) immobilize an antimicrobial in the matrix; 2) determine if the antimicrobial retains its functionality and 3) optimize the reactor design.The plasma zone will be obtained by increasing the voltage on an electrode structure until the electric field in the feed material (argon + monomer) yields electron avalanches. Results will be described using Red Delicious apples.Prospective matrix precursors are vanillin and cinnamic acid.A prospective bioactive compound is benzoic acid.

  14. Preparation and application of highly porous aerogel-based bioactive materials in dentistry

    NASA Astrophysics Data System (ADS)

    Kuttor, Andrea; Szalóki, Melinda; Rente, Tünde; Kerényi, Farkas; Bakó, József; Fábián, István; Lázár, István; Jenei, Attila; Hegedüs, Csaba

    2014-03-01

    In this study, the possibility of preparation and application of highly porous silica aerogel-based bioactive materials are presented. The aerogel was combined with hydroxyapatite and β-tricalcium phosphate as bioactive and osteoinductive agents. The porosity of aerogels was in the mesoporous region with a maximum pore diameter of 7.4 and 12.7 nm for the composite materials. The newly developed bioactive materials were characterized by scanning electron microscopy. The in vitro biological effect of these modified surfaces was also tested on SAOS-2 osteogenic sarcoma cells by confocal laser scanning microscopy.

  15. Potential Bioactive Compounds from Seaweed for Diabetes Management.

    PubMed

    Sharifuddin, Yusrizam; Chin, Yao-Xian; Lim, Phaik-Eem; Phang, Siew-Moi

    2015-08-21

    Diabetes mellitus is a group of metabolic disorders of the endocrine system characterised by hyperglycaemia. Type II diabetes mellitus (T2DM) constitutes the majority of diabetes cases around the world and are due to unhealthy diet, sedentary lifestyle, as well as rise of obesity in the population, which warrants the search for new preventive and treatment strategies. Improved comprehension of T2DM pathophysiology provided various new agents and approaches against T2DM including via nutritional and lifestyle interventions. Seaweeds are rich in dietary fibres, unsaturated fatty acids, and polyphenolic compounds. Many of these seaweed compositions have been reported to be beneficial to human health including in managing diabetes. In this review, we discussed the diversity of seaweed composition and bioactive compounds which are potentially useful in preventing or managing T2DM by targeting various pharmacologically relevant routes including inhibition of enzymes such as α-glucosidase, α-amylase, lipase, aldose reductase, protein tyrosine phosphatase 1B (PTP1B) and dipeptidyl-peptidase-4 (DPP-4). Other mechanisms of action identified, such as anti-inflammatory, induction of hepatic antioxidant enzymes' activities, stimulation of glucose transport and incretin hormones release, as well as β-cell cytoprotection, were also discussed by taking into consideration numerous in vitro, in vivo, and human studies involving seaweed and seaweed-derived agents.

  16. Potential Bioactive Compounds from Seaweed for Diabetes Management

    PubMed Central

    Sharifuddin, Yusrizam; Chin, Yao-Xian; Lim, Phaik-Eem; Phang, Siew-Moi

    2015-01-01

    Diabetes mellitus is a group of metabolic disorders of the endocrine system characterised by hyperglycaemia. Type II diabetes mellitus (T2DM) constitutes the majority of diabetes cases around the world and are due to unhealthy diet, sedentary lifestyle, as well as rise of obesity in the population, which warrants the search for new preventive and treatment strategies. Improved comprehension of T2DM pathophysiology provided various new agents and approaches against T2DM including via nutritional and lifestyle interventions. Seaweeds are rich in dietary fibres, unsaturated fatty acids, and polyphenolic compounds. Many of these seaweed compositions have been reported to be beneficial to human health including in managing diabetes. In this review, we discussed the diversity of seaweed composition and bioactive compounds which are potentially useful in preventing or managing T2DM by targeting various pharmacologically relevant routes including inhibition of enzymes such as α-glucosidase, α-amylase, lipase, aldose reductase, protein tyrosine phosphatase 1B (PTP1B) and dipeptidyl-peptidase-4 (DPP-4). Other mechanisms of action identified, such as anti-inflammatory, induction of hepatic antioxidant enzymes’ activities, stimulation of glucose transport and incretin hormones release, as well as β-cell cytoprotection, were also discussed by taking into consideration numerous in vitro, in vivo, and human studies involving seaweed and seaweed-derived agents. PMID:26308010

  17. Synthesis, bioactivity and zeta potential investigations of chlorine and fluorine substituted hydroxyapatite.

    PubMed

    Fahami, Abbas; Beall, Gary W; Betancourt, Tania

    2016-02-01

    Chlorine and fluorine substituted hydroxyapatites (HA-Cl-F) with different degrees of ion replacement were successfully prepared by the one step mechanochemical activation method. X-ray diffraction (XRD) and FT-IR spectra indicated that substitution of these anions in milled powders resulted in the formation of pure hydroxyapatite phase except for the small observed change in the lattice parameters and unit cell volumes of the resultant hydroxyapatite. Microscopic observations showed that the milled product had a cluster-like structure made up of polygonal and spherical particles with an average particle size of approximately ranged from 20±5 to 70±5nm. The zeta potential of milled samples was performed at three different pH (5, 7.4, and 9). The obtained zeta potential values were negative for all three pH values. Negative zeta potential was described to favor osseointegration, apatite nucleation, and bone regeneration. The bioactivity of samples was investigated on sintered pellets soaked in simulated body fluid (SBF) solution and apatite crystals formed on the surface of the pellets after being incubated for 14days. Zeta potential analysis and bioactivity experiment suggested that HA-Cl-F will lead to the formation of new apatite particles and therefore be a potential implant material.

  18. Antibacterial and antifungal potential of Ga-bioactive glass and Ga-bioactive glass/polymeric hydrogel composites.

    PubMed

    Keenan, T J; Placek, L M; Hall, M M; Wren, A W

    2016-03-21

    A bioactive glass series (0.42SiO2 -0.10Na2 O-0.08CaO-(0.40 - x)ZnO-(x)Ga2 O3 ) was synthesized, and it is efficacy against the Gram (-ve) bacteria Escherichia coli (E. coli), the Gram (+ve) bacteria Staphylococcus aureus (S. aureus), and the fungus Candida albicans (C. albicans), were characterized through liquid broth analysis. The glass series was also seeded in CMC-Dex hydrogels at three different loadings (0.05, 0.10, and 0.25 m(2) ), and the antibacterial and antifungal efficacies of the resulting composites were characterized using both liquid broth and agar diffusion analysis. Liquid broth analysis was conducted using liquid extracts, which for glass samples were obtained after incubation for up to 30 days in both ultrapure water and phosphate buffered saline (PBS), while glass-hydrogel extracts were obtained solely in PBS. Glass extracts (water) decreased C. albicans viability, while those obtained in PBS decreased the viability of both E. coli and C. albicans. Glass-hydrogel extracts exhibited slight inhibition of E. coli and C. albicans. However, none of the liquid extracts decreased S. aureus viability. Glass-hydrogel composites produced inhibition zones in all three microbial cultures, with the greatest efficacy against C. albicans. The results of this study suggest these materials have potential as bone void-filling materials which display antifungal, and possibly, antibacterial properties. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2016.

  19. Production of the bioactive polysaccharide schizophyllan from renewable cellulosic materials

    USDA-ARS?s Scientific Manuscript database

    Schizophyllan is a bioactive homoglucan with a ß-1,3-linked backbone and ß-1,6-linked side chains of single glucose units at every other residue. It is produced by the ubiquitous mushroom, Schizophyllum commune. Schizophyllan acts as a biological response modifier and a non-specific stimulator of ...

  20. Therapeutic potential of dairy bioactive peptides: A Contemporary Perspectives.

    PubMed

    Sultan, Saira; Huma, Nuzhat; Butt, Masood Sadiq; Aleem, Muhammad; Abbas, Munawar

    2016-02-06

    Dairy products are associated with numerous health benefits. They are good source of nutrients like carbohydrates, protein (bioactive peptides), lipids, minerals and vitamins which are essential for growth, development and maintenance of the human body. Accordingly, dairy bioactive peptides are one of targeted compounds present in different dairy products. Dairy bioactive compounds can be classified as anti-hypertensive, anti-oxidative, immmunomodulant, anti-mutagenic, anti-microbial, opoid, anti-thrombotic, anti-obesity and mineral-binding agents depending upon biological functions. These bioactive peptides can easily be produced by enzymatic hydrolysis, during fermentation and gastrointestinal digestion. For the reason, fermented dairy products like yogurt, cheese and sour milk are gaining popularity worldwide and considered excellent sources of dairy peptides. Furthermore, fermented and non-fermented dairy products are associated with lower risks of hypertension, coagulopathy, stroke and cancer insurgences. The current review article is an attempt to disseminate general information about dairy peptides and their health claims to scientists, allied stakeholders and certainly readers.

  1. Evaluation of the efficacy of a bioactive synthetic graft material in the treatment of intrabony periodontal defects

    PubMed Central

    Grover, Vishakha; Kapoor, Anoop; Malhotra, Ranjan; Uppal, Ranjit Singh

    2013-01-01

    Background: Bioactive ceramic fillers are synthetic materials which have shown the potential to enhance bone formation. The purpose of this study was to evaluate the efficacy of a bioactive synthetic graft material in the treatment of intrabony periodontal defects. Materials and Methods: Fourteen intrabony defects in twelve systemically healthy subjects having moderate to severe chronic periodontitis were evaluated after bone grafting with bioactive ceramic filler for a period of 6 months. Clinical and radiographic evaluations were made at baseline, at 3 and 6 months following surgery. Results: Mean radiographic defect fill of 64.76% (2.49±0.5 mm) was observed in 6 months, which was statistically significant. A statistically significant relative attachment level gain of 2.71±1.13 mm and probing pocket depth reduction of 4.21±1.18 mm was recorded at the end of the study. A significant decrease in mobility and gingival index was observed. Conclusions: Bioactive glass is an efficacious treatment option for the reconstruction of intrabony periodontal defects as it led to statistically significant improvements in the clinical and radiographic parameters. PMID:23633783

  2. Dental repair material: a resin-modified glass-ionomer bioactive ionic resin-based composite.

    PubMed

    Croll, Theodore P; Berg, Joel H; Donly, Kevin J

    2015-01-01

    This report documents treatment and repair of three carious teeth that were restored with a new dental repair material that features the characteristics of both resin-modified glass-ionomer restorative cement (RMGI) and resin-based composite (RBC). The restorative products presented are reported by the manufacturer to be the first bioactive dental materials with an ionic resin matrix, a shock-absorbing resin component, and bioactive fillers that mimic the physical and chemical properties of natural teeth. The restorative material and base/liner, which feature three hardening mechanisms, could prove to be a notable advancement in the adhesive dentistry restorative materials continuum.

  3. Bioactive proteins and peptides isolated from Chinese medicines with pharmaceutical potential.

    PubMed

    Wong, Kam Lok; Wong, Ricky Ngok Shun; Zhang, Liang; Liu, Wing Keung; Ng, Tzi Bun; Shaw, Pang Chui; Kwok, Philip Chi Lip; Lai, Yau Ming; Zhang, Zhang Jin; Zhang, Yanbo; Tong, Yao; Cheung, Ho-Pan; Lu, Jia; Sze, Stephen Cho Wing

    2014-01-01

    Some protein pharmaceuticals from Chinese medicine have been developed to treat cardiovascular diseases, genetic diseases, and cancer. Bioactive proteins with various pharmacological properties have been successfully isolated from animals such as Hirudo medicinalis (medicinal leech), Eisenia fetida (earthworm), and Mesobuthus martensii (Chinese scorpion), and from herbal medicines derived from species such as Cordyceps militaris, Ganoderma, Momordica cochinchinensis, Viscum album, Poria cocos, Senna obtusifolia, Panax notoginseng, Smilax glabra, Ginkgo biloba, Dioscorea batatas, and Trichosanthes kirilowii. This article reviews the isolation methods, molecular characteristics, bioactivities, pharmacological properties, and potential uses of bioactive proteins originating from these Chinese medicines.

  4. Bioactive proteins and peptides isolated from Chinese medicines with pharmaceutical potential

    PubMed Central

    2014-01-01

    Some protein pharmaceuticals from Chinese medicine have been developed to treat cardiovascular diseases, genetic diseases, and cancer. Bioactive proteins with various pharmacological properties have been successfully isolated from animals such as Hirudo medicinalis (medicinal leech), Eisenia fetida (earthworm), and Mesobuthus martensii (Chinese scorpion), and from herbal medicines derived from species such as Cordyceps militaris, Ganoderma, Momordica cochinchinensis, Viscum album, Poria cocos, Senna obtusifolia, Panax notoginseng, Smilax glabra, Ginkgo biloba, Dioscorea batatas, and Trichosanthes kirilowii. This article reviews the isolation methods, molecular characteristics, bioactivities, pharmacological properties, and potential uses of bioactive proteins originating from these Chinese medicines. PMID:25067942

  5. Evaluation of the efficacy of a bioactive synthetic graft material in the treatment of intrabony periodontal defects.

    PubMed

    Grover, Vishakha; Kapoor, Anoop; Malhotra, Ranjan; Uppal, Ranjit Singh

    2013-01-01

    Bioactive ceramic fillers are synthetic materials which have shown the potential to enhance bone formation. The purpose of this study was to evaluate the efficacy of a bioactive synthetic graft material in the treatment of intrabony periodontal defects. Fourteen intrabony defects in twelve systemically healthy subjects having moderate to severe chronic periodontitis were evaluated after bone grafting with bioactive ceramic filler for a period of 6 months. Clinical and radiographic evaluations were made at baseline, at 3 and 6 months following surgery. Mean radiographic defect fill of 64.76% (2.49±0.5 mm) was observed in 6 months, which was statistically significant. A statistically significant relative attachment level gain of 2.71±1.13 mm and probing pocket depth reduction of 4.21±1.18 mm was recorded at the end of the study. A significant decrease in mobility and gingival index was observed. Bioactive glass is an efficacious treatment option for the reconstruction of intrabony periodontal defects as it led to statistically significant improvements in the clinical and radiographic parameters.

  6. Strategies to develop endogenous stem cell-recruiting bioactive materials for tissue repair and regeneration.

    PubMed

    Pacelli, Settimio; Basu, Sayantani; Whitlow, Jonathan; Chakravarti, Aparna; Acosta, Francisca; Varshney, Arushi; Modaresi, Saman; Berkland, Cory; Paul, Arghya

    2017-07-19

    A leading strategy in tissue engineering is the design of biomimetic scaffolds that stimulate the body's repair mechanisms through the recruitment of endogenous stem cells to sites of injury. Approaches that employ the use of chemoattractant gradients to guide tissue regeneration without external cell sources are favored over traditional cell-based therapies that have limited potential for clinical translation. Following this concept, bioactive scaffolds can be engineered to provide a temporally and spatially controlled release of biological cues, with the possibility to mimic the complex signaling patterns of endogenous tissue regeneration. Another effective way to regulate stem cell activity is to leverage the inherent chemotactic properties of extracellular matrix (ECM)-based materials to build versatile cell-instructive platforms. This review introduces the concept of endogenous stem cell recruitment, and provides a comprehensive overview of the strategies available to achieve effective cardiovascular and bone tissue regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Bio-active restorative materials with antibacterial effects: new dimension of innovation in restorative dentistry.

    PubMed

    Imazato, Satoshi

    2009-01-01

    Restorative materials in the new era should be "bio-active", and antibacterial effects are highlighted as one of the important properties. In order to achieve resin-based restoratives with antibacterial effects, an antibacterial monomer MDPB has been developed. The primer incorporating MDPB demonstrated cavity-disinfecting effects, and the world's first antibacterial adhesive system employing the MDPB-containing primer was successfully commercialized. MDPB is potentially applicable to various restoratives since immobilization of the antibacterial component by polymerization of MDPB enables no deterioration in mechanical properties of cured resins and exhibition of inhibitory effects against bacterial growth on their surfaces. For glass-ionomer cements used for atraumatic restorative treatment, the approach to provide antibacterial activity has been attempted by addition of chlorhexidine. Incorporation of 1% chlorhexidine diacetate was found to be optimal to give appropriate antibacterial and physical properties, being effective to reduce the bacteria in affected and infected dentin in vivo.

  8. Experimental studies on a new bioactive material: HAIonomer cements.

    PubMed

    Yap, A U J; Pek, Y S; Kumar, R A; Cheang, P; Khor, K A

    2002-02-01

    promising material, which possess good mechanical properties. Potential uses of this new material include bone cements and performed implants for hard tissue replacement in the field of otological, oral-maxillofacial and orthopedic surgery.

  9. Bioactive treatment promotes osteoblast differentiation on titanium materials fabricated by selective laser melting technology.

    PubMed

    Tsukanaka, Masako; Fujibayashi, Shunsuke; Takemoto, Mitsuru; Matsushita, Tomiharu; Kokubo, Tadashi; Nakamura, Takashi; Sasaki, Kiyoyuki; Matsuda, Shuichi

    2016-01-01

    Selective laser melting (SLM) technology is useful for the fabrication of porous titanium implants with complex shapes and structures. The materials fabricated by SLM characteristically have a very rough surface (average surface roughness, Ra=24.58 µm). In this study, we evaluated morphologically and biochemically the specific effects of this very rough surface and the additional effects of a bioactive treatment on osteoblast proliferation and differentiation. Flat-rolled titanium materials (Ra=1.02 µm) were used as the controls. On the treated materials fabricated by SLM, we observed enhanced osteoblast differentiation compared with the flat-rolled materials and the untreated materials fabricated by SLM. No significant differences were observed between the flat-rolled materials and the untreated materials fabricated by SLM in their effects on osteoblast differentiation. We concluded that the very rough surface fabricated by SLM had to undergo a bioactive treatment to obtain a positive effect on osteoblast differentiation.

  10. Marine carotenoids: Bioactivities and potential benefits to human health.

    PubMed

    Chuyen, Hoang Van; Eun, Jong-Bang

    2017-08-13

    Among natural pigments, carotenoids play important roles in physiological functions. The characteristics of carotenoids and their effects on human health have been reported for a long time, but most studies have focused on carotenoids from vegetables, fruits, and other parts of higher plants. Few reports are available on carotenoids from marine sources, such as seaweeds, microalgae, and marine animals, which have attracted attention in recent decades. Hundreds of carotenoids have been identified and isolated from marine organisms and their beneficial physiological functions, such as anticancer, antiobesity, antidiabetic, anti-inflammatory, and cardioprotective activities have been reported. The purpose of this review is to discuss the literature on the beneficial bioactivities of some of the most abundant marine carotenoids, including fucoxanthin, astaxanthin, cantaxanthin, peridinin, fucoxanthinol, and halocynthiaxanthin.

  11. Cancer Stem Cells: Potential Target for Bioactive Food Components

    PubMed Central

    Kim, Young S.; Farrar, William; Colburn, Nancy H.; Milner, John A.

    2015-01-01

    Cancer stem cells often have phenotypic and functional characteristics similar to normal stem cells including the properties of self-renewal and differentiation. Recent findings suggest that uncontrolled self-renewal may explain cancer relapses and may represent a critical target for cancer prevention. It is conceivable that the loss of regulatory molecules resulting from inappropriate consumption of specific foods and their constituents may foster the aberrant self-renewal of cancer stem cells. In fact, increasing evidence points to the network delivering signals for self-renewal from extracellular compartments to the nucleus including changes in stem cell environments, inducible expression of microRNAs, hyperplastic nuclear chromatin structures, and the on/off of differentiation process as possible sites of action for bioactive food components. Diverse dietary constituents such as vitamins A and D, genistein, (−)-epigallocatechin-3-gallate (EGCG), sulforaphane, curcumin, piperine, theanine, and choline have been shown to modify self-renewal properties of cancer stem cells. The ability of these bioactive food components to influence the balance between proliferative and quiescent cells by regulating critical feedback molecules in the network including dickkopf 1 (DKK-1), secreted frizzled-related protein 2 (sFRP2), B-cell-specific Moloney murine leukemia virus integration site 1 (Bmi-1), and cyclin-dependent kinase 6 (CDK6) may account for their biological response. Overall, the response to food components does not appear to be tissue or organ specific, suggesting there may be common cellular mechanisms. Unquestionably, additional studies are needed to clarify the physiological role of these dietary components in preventing the resistance of tumor cells to traditional drugs and cancer recurrence. PMID:22704055

  12. Preparation, bioactivity, and application of novel biocidal materials

    NASA Astrophysics Data System (ADS)

    Wu, Rong

    In this study, several novel N-halamine precursors were synthesized. These surface coupling agents were bonded to the surfaces of cotton fabric, cotton gauze, paper, glass, and sand. Once they were activated using household bleach, the surfaces and materials became biocidal. Possible uses for the biocidal cotton are in protective garments for hospital personnel and those who must fight against bioterrorism. The treated cotton gauze may be used to make an antimicrobial mask to stop infective pathogen transcontamination. Biocidal sand has the potential to be used as a disinfectant in a filter for wastewater or municipal water treatment. In fact, the N-halamine siloxanes can be applied to many other surfaces. The results of biocidal efficacy of some of the treated surfaces will be presented in this study. Several new hydantoinyl diols and quaternary ammonium hydantoinyl diols were prepared in this work also. They were copolymerized with commercial water borne acrylic polyol and commercial isocyanate to form polyurethane coatings. The biocidal polyurethane coatings were produced after activation by chlorination. Those diols also reacted with a two-component epoxy paint to render the paint antimicrobial. Several novel biocidal polymeric resins were synthesized by attachment of N-halamine moieties to the commercial polymer supported beads such as Merrifield resin and Amberlite IRA-67 ionic resin. The Merrifield resin and Amberlite IRA-67 ionic resin also were grafted with N-halamine functionality as well as with the N,N-dimethyl-dodecylamine moiety via 1,2-dichloroethane. Finally, several quaternary ammonium N-halamine polymers were prepared. Direct copolymerization of (triethoxysilyl)propyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro-[4,5]-decane-2,4-dione (TTDD-Si), or 3-(trimethoxysilyl)propyl-5,5-dimethylhydantoin (BA-1 ') with 3-(trimethoxysilylpropyl)dimethyloctadecyl ammonium chloride (DC 5700) produced dual functionality and water soluble biocidal materials and

  13. Design of in vitro bioactive hybrid materials from the first generation of amine dendrimers as nanobuilding blocks.

    PubMed

    González, Blanca; Colilla, Montserrat; Vallet-Regí, María

    2013-04-08

    In this work, the first generation of poly(propyleneimine) dendrimers were functionalized with alkoxysilane terminal groups and subjected to one of two different sol-gel process that followed two different catalytic pathways, that is base- or acid-catalyzed pathways. Thus, two series of new organic-inorganic hybrid materials were obtained in the form of monolithic pieces with differences in terms of both morphology and silanol content, which originated from the different sol-gel pathway that was followed. Moreover, calcium ions were added into the hybrid composition to promote in vitro bioactivity and phosphorous sources were used during the sol-gel step to obtain an earlier bioactive response. Characterization of these organic-inorganic hybrid materials was performed by means of thermogravimetric and elemental analyses, Fourier transform infrared spectroscopy (FTIR), solid state (13)C, (29)Si and (31)P magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy, N2-adsorption isotherms, mercury-intrusion porosimetry, and ζ-potential measurements. The in vitro bioactivity of the dendritic hybrid networks was evaluated by soaking the materials in simulated body fluid and the results were explained in terms of the composition of the hybrids and the sol-gel route that was followed to prepare them. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Bioactive compounds from marine sponges and their symbiotic microbes: a potential source of nutraceuticals.

    PubMed

    Kim, Se-Kwon; Dewapriya, Pradeep

    2012-01-01

    Sponges are considered as the chemical factory in marine environment because of its immense production of chemically diverse compounds. Other than the chemical diversity, these compounds possess remarkable bioactivities. This great potential has aroused applications of sponge-derived compounds as therapeutics and at present, a number of promising compounds are in clinical and preclinical trials. Recently, nutraceuticals have received considerable interest among the health conscious community because of its multiple therapeutic effects. Natural health-promoting substances gain continuous popularity as nutraceuticals due to its reduced risk of side effects. This overview discusses the potentials of marine sponge-derived bioactivities as natural health-promoting compounds.

  15. Biological activities and potential health benefits of bioactive peptides derived from marine organisms.

    PubMed

    Ngo, Dai-Hung; Vo, Thanh-Sang; Ngo, Dai-Nghiep; Wijesekara, Isuru; Kim, Se-Kwon

    2012-11-01

    Marine organisms have been recognized as rich sources of bioactive compounds with valuable nutraceutical and pharmaceutical potentials. Recently, marine bioactive peptides have gained much attention because of their numerous health beneficial effects. Notably, these peptides exhibit various biological activities such as antioxidant, anti-hypertensive, anti-human immunodeficiency virus, anti-proliferative, anticoagulant, calcium-binding, anti-obesity and anti-diabetic activities. This review mainly presents biological activities of peptides from marine organisms and emphasizing their potential applications in foods as well as pharmaceutical areas.

  16. Optimization of liquid culture conditions of Philippine wild edible mushrooms as potential source of bioactive lipids

    USDA-ARS?s Scientific Manuscript database

    With remarkable bioactivities and delightful taste, mushrooms have been a commercial nutraceutical around the world. Mushrooms are cultivated on solid materials. Here we report the successful cultivation of four Philippine edible mushrooms in liquid medium. This work highlights the optimal liquid cu...

  17. Research on the preparation, biocompatibility and bioactivity of magnesium matrix hydroxyapatite composite material.

    PubMed

    Linsheng, Li; Guoxiang, Lin; Lihui, Li

    2016-08-12

    In this paper, magnesium matrix hydroxyapatite composite material was prepared by electrophoretic deposition method. The optimal process parameters of electrophoretic deposition were HA suspension concentration of 0.02 kg/L, aging time of 10 days and voltage of 60 V. Animal experiment and SBF immersion experiment were used to test the biocompatibility and bioactivity of this material respectively. The SD rats were divided into control group and implant group. The implant surrounding tissue was taken to do tissue biopsy, HE dyed and organizational analysis after a certain amount of time in the SD rat body. The biological composite material was soaked in SBF solution under homeothermic condition. After 40 days, the bioactivity of the biological composite material was evaluated by testing the growth ability of apatite on composite material. The experiment results showed that magnesium matrix hydroxyapatite biological composite material was successfully prepared by electrophoretic deposition method. Tissue hyperplasia, connective tissue and new blood vessels appeared in the implant surrounding soft tissue. No infiltration of inflammatory cells of lymphocytes and megakaryocytes around the implant was found. After soaked in SBF solution, a layer bone-like apatite was found on the surface of magnesium matrix hydroxyapatite biological composite material. The magnesium matrix hydroxyapatite biological composite material could promot calcium deposition and induce bone-like apatite formation with no cytotoxicity and good biocompatibility and bioactivity.

  18. Therapeutic potential of abalone and status of bioactive molecules: A comprehensive review.

    PubMed

    Suleria, H A R; Masci, P P; Gobe, G C; Osborne, S A

    2017-05-24

    Marine organisms are increasingly being investigated as sources of bioactive molecules with therapeutic applications as nutraceuticals and pharmaceuticals. In particular, nutraceuticals are gaining popularity worldwide owing to their therapeutic potential and incorporation in functional foods and dietary supplements. Abalone, a marine gastropod, contains a variety of bioactive compounds with anti-oxidant, anti-thrombotic, anti-inflammatory, anti-microbial, and anti-cancer activities. For thousands of years different cultures have used abalone as a traditional functional food believing consumption provides health benefits. Abalone meat is one of the most precious commodities in Asian markets where it is considered a culinary delicacy. Recent research has revealed that abalone is composed of many vital moieties like polysaccharides, proteins, and fatty acids that provide health benefits beyond basic nutrition. A review of past and present research is presented with relevance to the therapeutic potential of bioactive molecules from abalone.

  19. Potential interaction of natural dietary bioactive compounds with COX-2.

    PubMed

    Maldonado-Rojas, Wilson; Olivero-Verbel, Jesus

    2011-09-01

    Bioactive natural products present in the diet play an important role in several biological processes, and many have been involved in the alleviation and control of inflammation-related diseases. These actions have been linked to both gene expression modulation of pro-inflammatory enzymes, such as cyclooxygenase 2 (COX-2), and to an action involving a direct inhibitory binding on this protein. In this study, several food-related compounds with known gene regulatory action on inflammation have been examined in silico as COX-2 ligands, utilizing AutoDock Vina, GOLD and Surflex-Dock (SYBYL) as docking protocols. Curcumin and all-trans retinoic acid presented the maximum absolute AutoDock Vina-derived binding affinities (9.3 kcal/mol), but genistein, apigenin, cyanidin, kaempferol, and docosahexaenoic acid, were close to this value. AutoDock Vina affinities and GOLD scores for several known COX-2 inhibitors significatively correlated with reported median inhibitory concentrations (R² = 0.462, P < 0.001 and R² = 0.238, P = 0.029, respectively), supporting the computational reliability of the predictions made by our docking simulations. Moreover, docking analysis insinuate the synergistic action of curcumin on celecoxib-induced inhibition of COX-2 may occur allosterically, as this natural compound docks to a place different from the inhibitor binding site. These results suggest that the anti-inflammatory properties of some food-derived molecules could be the result of their direct binding capabilities to COX-2, and this process can be modeled using protein-ligand docking methodologies.

  20. Sorghum (Sorghum bicolor L.): Nutrients, bioactive compounds, and potential impact on human health.

    PubMed

    de Morais Cardoso, Leandro; Pinheiro, Soraia Silva; Martino, Hércia Stampini Duarte; Pinheiro-Sant'Ana, Helena Maria

    2017-01-22

    Sorghum is the fifth most produced cereal in the world and is a source of nutrients and bioactive compounds for the human diet. We summarize the recent findings concerning the nutrients and bioactive compounds of sorghum and its potential impact on human health, analyzing the limitations and positive points of the studies and proposing directions for future research. Sorghum is basically composed of starch, which is more slowly digested than that of other cereals, has low digestibility proteins and unsaturated lipids, and is a source of some minerals and vitamins. Furthermore, most sorghum varieties are rich in phenolic compounds, especially 3-deoxyanthocyanidins and tannins. The results obtained in vitro and in animals have shown that phenolics compounds and fat soluble compounds (polycosanols) isolated from sorghum benefit the gut microbiota and parameters related to obesity, oxidative stress, inflammation, diabetes, dyslipidemia, cancer, and hypertension. The effects of whole sorghum and its fractions on human health need to be evaluated. In conclusion, sorghum is a source of nutrients and bioactive compounds, especially 3-deoxyanthocyanidins, tannins, and polycosanols, which beneficially modulate, in vitro and in animals, parameters related to noncommunicable diseases. Studies should be conducted to evaluate the effects of different processing on protein and starch digestibility of sorghum as well as on the profile and bioavailability of its bioactive compounds, especially 3-deoxyanthocyanidins and tannins. Furthermore, the benefits resulting from the interaction of bioactive compounds in sorghum and human microbiota should be studied.

  1. Potential anticancer properties of bioactive compounds of Gymnema sylvestre and its biofunctionalized silver nanoparticles.

    PubMed

    Arunachalam, Kantha Deivi; Arun, Lilly Baptista; Annamalai, Sathesh Kumar; Arunachalam, Aarrthy M

    2015-01-01

    Gymnema sylvestre is an ethno-pharmacologically important medicinal plant used in many polyherbal formulations for its potential health benefits. Silver nanoparticles (SNPs) were biofunctionalized using aqueous leaf extracts of G. sylvestre. The anticancer properties of the bioactive compounds and the biofunctionalized SNPs were compared using the HT29 human adenoma colon cancer cell line. The preliminary phytochemical screening for bioactive compounds from aqueous extracts revealed the presence of alkaloids, triterpenes, flavonoids, steroids, and saponins. Biofunctionalized SNPs were synthesized using silver nitrate and characterized by ultraviolet-visible spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, and X-ray diffraction for size and shape. The characterized biofunctionalized G. sylvestre were tested for its in vitro anticancer activity against HT29 human colon adenocarcinoma cells. The biofunctionlized G. sylvestre SNPs showed the surface plasmon resonance band at 430 nm. The scanning electron microscopy images showed the presence of spherical nanoparticles of various sizes, which were further determined using the Scherrer equation. In vitro cytotoxic activity of the biofunctionalized green-synthesized SNPs (GSNPs) indicated that the sensitivity of HT29 human colon adenocarcinoma cells for cytotoxic drugs is higher than that of Vero cell line for the same cytotoxic agents and also higher than the bioactive compound of the aqueous extract. Our results show that the anticancer properties of the bioactive compounds of G. sylvestre can be enhanced through biofunctionalizing the SNPs using the bioactive compounds present in the plant extract without compromising their medicinal properties.

  2. Effect of postharvest handling practices on phytochemical concentrations and bioactive potential in wild blueberry fruit

    USDA-ARS?s Scientific Manuscript database

    In this study, we quantified anthocyanin (ANC), proanthocyanidin (PAC), and chlorogenic acid (CA) concentrations in wild blueberry fruit (WBB) exposed to a variety of postharvest handling practices relevant to consumers and to industry. Additionally, we analyzed the bioactive potential of WBB subjec...

  3. Bioactivity evaluation of three calcium silicate-based endodontic materials.

    PubMed

    Han, L; Okiji, T

    2013-09-01

    To compare white ProRoot MTA (WMTA), EndoSequence BC sealer (BC sealer) and Biodentine with regard to their ability to produce apatites and cause Ca and Si incorporation in adjacent human root canal dentine after immersion in phosphate-buffered saline (PBS). Root sections of human single-rooted teeth were filled with one of the materials and immersed in PBS for 1, 7, 30 or 90 days (n = 5 each). Morphology and elemental composition of surface precipitates and interfacial dentine were analysed using a wavelength-dispersive X-ray spectroscopy electron probe microanalyser with image observation function. Ca- and Si-incorporation depths in the interfacial dentine were measured. In addition, the amount of Ca ions released from the test materials was measured by EDTA titration. All materials produced surface precipitates of acicular or lath-like morphology with Ca/P ratio of 1.6 : 2.0. Within dentinal tubules, the three materials formed tag-like structures that were frequently composed of Ca- and P-rich and Si-poor materials, suggesting intratubular precipitation. Ca- and Si-incorporation depths were in the order of Biodentine > WMTA > BC sealer, with a significant difference between BC sealer and the others at several time-points (P < 0.05, anova and Tukey's honestly significant difference test). The concentration of released Ca ions was in the order of Biodentine > WMTA > BC sealer with significant differences between the materials (P < 0.05). Compared with Biodentine and WMTA, BC sealer showed less Ca ion release and did not show Ca and Si incorporation as deeply in human root canal dentine when immersed in PBS for up to 90 days. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  4. Lipoic Acid Gold Nanoparticles Functionalized with Organic Compounds as Bioactive Materials

    PubMed Central

    Turcu, Ioana; Zarafu, Irina; Popa, Marcela; Chifiriuc, Mariana Carmen; Bleotu, Coralia; Culita, Daniela; Ghica, Corneliu; Ionita, Petre

    2017-01-01

    Water soluble gold nanoparticles protected by lipoic acid were obtained and further functionalized by standard coupling reaction with 1-naphtylamine, 4-aminoantipyrine, and 4′-aminobenzo-15-crown-5 ether. Derivatives of lipoic acid with 1-naphtylamine, 4-aminoantipyrine, and 4′-aminobenzo-15-crown-5 ether were also obtained and characterized. All these were tested for their antimicrobial activity, as well as for their influence on mammalian cell viability and cellular cycle. In all cases a decreased antimicrobial activity of the obtained bioactive nanoparticles was observed as compared with the organic compounds, proving that a possible inactivation of the bioactive groups could occur during functionalization. However, both the gold nanoparticles as well as the functionalized bioactive nanosystems proved to be biocompatible at concentrations lower than 50 µg/mL, as revealed by the cellular viability and cell cycle assay, demonstrating their potential for the development of novel antimicrobial agents. PMID:28336877

  5. Chemical, Bioactive, and Antioxidant Potential of Twenty Wild Culinary Mushroom Species.

    PubMed

    Sharma, S K; Gautam, N

    2015-01-01

    The chemical, bioactive, and antioxidant potential of twenty wild culinary mushroom species being consumed by the people of northern Himalayan regions has been evaluated for the first time in the present study. Nutrients analyzed include protein, crude fat, fibres, carbohydrates, and monosaccharides. Besides, preliminary study on the detection of toxic compounds was done on these species. Bioactive compounds evaluated are fatty acids, amino acids, tocopherol content, carotenoids (β-carotene, lycopene), flavonoids, ascorbic acid, and anthocyanidins. Fruitbodies extract of all the species was tested for different types of antioxidant assays. Although differences were observed in the net values of individual species all the species were found to be rich in protein, and carbohydrates and low in fat. Glucose was found to be the major monosaccharide. Predominance of UFA (65-70%) over SFA (30-35%) was observed in all the species with considerable amounts of other bioactive compounds. All the species showed higher effectiveness for antioxidant capacities.

  6. Chemical, Bioactive, and Antioxidant Potential of Twenty Wild Culinary Mushroom Species

    PubMed Central

    Sharma, S. K.; Gautam, N.

    2015-01-01

    The chemical, bioactive, and antioxidant potential of twenty wild culinary mushroom species being consumed by the people of northern Himalayan regions has been evaluated for the first time in the present study. Nutrients analyzed include protein, crude fat, fibres, carbohydrates, and monosaccharides. Besides, preliminary study on the detection of toxic compounds was done on these species. Bioactive compounds evaluated are fatty acids, amino acids, tocopherol content, carotenoids (β-carotene, lycopene), flavonoids, ascorbic acid, and anthocyanidins. Fruitbodies extract of all the species was tested for different types of antioxidant assays. Although differences were observed in the net values of individual species all the species were found to be rich in protein, and carbohydrates and low in fat. Glucose was found to be the major monosaccharide. Predominance of UFA (65–70%) over SFA (30–35%) was observed in all the species with considerable amounts of other bioactive compounds. All the species showed higher effectiveness for antioxidant capacities. PMID:26199938

  7. Bioactive peptides derived from milk proteins and their health beneficial potentials: an update.

    PubMed

    Nagpal, Ravinder; Behare, Pradip; Rana, Rajiv; Kumar, Ashwani; Kumar, Manoj; Arora, Sanu; Morotta, Fransesco; Jain, Shalini; Yadav, Hariom

    2011-01-01

    It has been well recognized that dietary proteins provide a rich source of biologically active peptides. Today, milk proteins are considered the most important source of bioactive peptides and an increasing number of bioactive peptides have been identified in milk protein hydrolysates and fermented dairy products. Bioactive peptides derived from milk proteins offer a promising approach for the promotion of health by means of a tailored diet and provide interesting opportunities to the dairy industry for expansion of its field of operation. The potential health benefits of milk protein-derived peptides have been a subject of growing commercial interest in the context of health-promoting functional foods. Hence, these peptides are being incorporated in the form of ingredients in functional and novel foods, dietary supplements and even pharmaceuticals with the purpose of delivering specific health benefits.

  8. Polydopamine-mediated immobilization of multiple bioactive molecules for the development of functional vascular graft materials.

    PubMed

    Lee, Yu Bin; Shin, Young Min; Lee, Ji-Hye; Jun, Indong; Kang, Jae Kyeong; Park, Jong-Chul; Shin, Heungsoo

    2012-11-01

    In this study, we introduced a simple method for polydopamine-mediated immobilization of dual bioactive factors for the preparation of functionalized vascular graft materials. Polydopamine was deposited on elastic and biodegradable poly(lactic acid-co-ɛ-caprolactone) (PLCL) films, and a cell adhesive RGD-containing peptide and basic fibroblast growth factor were subsequently immobilized by simple dipping. We used an enzyme-linked immunosorbent assay and fluorescamine assay to confirm that we had stably immobilized bioactive molecules on the polydopamine-coated PLCL film in a reaction time-dependent manner. When human umbilical vein endothelial cells (HUVEC) were cultured on the prepared substrates, the number of adherent cells and proliferation of HUVEC for up to 14 days were greatest on the film immobilized with dual factors. On the other hand, the film immobilized with RGD peptide exhibited the highest migration speed compared to the other groups. The expression of cluster of differentiation 31 and von Willebrand factor, which indicates maturation of endothelial cells, was highly stimulated in the dual factor-immobilized group, and passively adsorbed factors showed a negligible effect. The immobilization of bioactive molecules inspired by polydopamine was successful, and adhesion, migration, proliferation and differentiation of HUVEC were synergistically accelerated by the presence of multiple signaling factors. Collectively, our results have demonstrated that a simple coating with polydopamine enables the immobilization of multiple bioactive molecules for preparation of polymeric functionalized vascular graft materials. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Sugar-decorated hydroxyapatite: an inorganic material bioactivated with carbohydrates.

    PubMed

    Russo, Laura; Landi, Elena; Tampieri, Anna; Natalello, Antonino; Doglia, Silvia M; Gabrielli, Luca; Cipolla, Laura; Nicotra, Francesco

    2011-09-06

    An efficient method for the direct and covalent decoration of granules of nanostructured apatite with a sample monosaccharide is presented; the hydroxyapatite material was directly functionalised with a short azido-containing spacer arm, to which α-propargyl glucopyranoside has been chemoselectively ligated by Huisgen-type cycloaddition. The 'glycosylated' hydroxypatite was characterised by its ability to interact with glucose recognising lectins. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Investigation of Mg and Zn doped 45S5 bioactive materials by XRD, FTIR and SEM techniques

    NASA Astrophysics Data System (ADS)

    Anand, Vikas; Singh, K. J.; Kaur, Kulwinder

    2014-04-01

    Magnesium and zinc doped 45S5 samples were prepared in the laboratory by sol gel technique., Structural properties of the samples have been studied by XRD, FTIR and SEM techniques. Both FTIR and XRD data indicate the primary bioactive behavior of the samples. Presented results may be useful to improve the antibacterial as well as osteoblast properties of the currently available bioactive materials.

  11. A review on anticancer potential of bioactive heterocycle quinoline.

    PubMed

    Afzal, Obaid; Kumar, Suresh; Haider, Md Rafi; Ali, Md Rahmat; Kumar, Rajiv; Jaggi, Manu; Bawa, Sandhya

    2015-06-05

    The advent of Camptothecin added a new dimension in the field anticancer drug development containing quinoline motif. Quinoline scaffold plays an important role in anticancer drug development as their derivatives have shown excellent results through different mechanism of action such as growth inhibitors by cell cycle arrest, apoptosis, inhibition of angiogenesis, disruption of cell migration, and modulation of nuclear receptor responsiveness. The anti-cancer potential of several of these derivatives have been demonstrated on various cancer cell lines. In this review we have compiled and discussed specifically the anticancer potential of quinoline derivatives, which could provide a low-height flying bird's eye view of the quinoline derived compounds to a medicinal chemist for a comprehensive and target oriented information for development of clinically viable anticancer drugs. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  12. Milk-derived bioactive peptides and their health promoting effects: a potential role in atherosclerosis.

    PubMed

    Marcone, Simone; Belton, Orina; Fitzgerald, Desmond J

    2017-01-01

    Bioactive peptides derived from milk proteins are food components that, in addition to their nutritional value, retain many biological properties and have therapeutic effects in several health disorders, including cardiovascular disease. Amongst these, atherosclerosis is the underlying cause of heart attack and strokes. It is a progressive dyslipidaemic and inflammatory disease where accumulation of oxidized lipids and inflammatory cells leads to the formation of an atherosclerotic plaque in the vessel wall. Milk-derived bioactive peptides can be released during gastrointestinal digestion, food processing or by enzymatic and bacterial fermentation and are considered to promote diverse beneficial effects such as lipid lowering, antihypertensive, immnomodulating, anti-inflammatory and antithrombotic effects. In this review, an overview of the diverse biological effects of these compounds is given, particularly focusing on their beneficial properties on cardiovascular disease and proposing novel mechanisms of action responsible for their bioactivity. Attempts to prevent cardiovascular diseases target modifications of several risk factors such as high blood pressure, obesity, high blood concentrations of lipids or insulin resistance. Milk-derived bioactive peptides are a source of health-enhancing components and the potential health benefit of these compounds has a growing commercial potential. Consequently, they have been incorporated as ingredients in functional foods, as dietary supplements and as pharmaceuticals to promote health and reduce risk of chronic diseases. © 2016 The British Pharmacological Society.

  13. Bioactive sterols from marine resources and their potential benefits for human health.

    PubMed

    Kim, Se-Kwon; Van Ta, Quang

    2012-01-01

    Bioactive agents from marine resources have shown their valuable health beneficial effects. Therefore, increase knowledge on novel functional ingredients with biological activities from marine animal and microbe has gained much attention. Sterols are recognized as potential in development functional food ingredients and pharmaceutical agents. Marine resources, with a great diversity, can be a very interesting natural resource of sterols. This chapter focuses on biological activities of marine animal and microbe sterols with potential health beneficial applications in functional foods and pharmaceuticals.

  14. Evaluation of bioactive potential of an Aloe vera sterol extract.

    PubMed

    Bawankar, Raksha; Deepti, V C; Singh, Pooja; Subashkumar, Rathinasamy; Vivekanandhan, Govindasamy; Babu, Subramanian

    2013-06-01

    We prepared a crude gel material from Aloe vera succulent leaf tissues. The ethanolic extract of lyophilized A. vera gel was used for the GC-MS analysis. Hexadecanoic acid (22.22%) was identified as major compound. Sitosterol and stigmasterol were found to be 2.89% and 2.1% in the extract. HPLC analysis was carried out to confirm the presence of stigmasterol. The concentration of sterol extract needed to scavenge DPPH free radical by 50% was calculated as 5.2 mg mL(-1). In the FRAP assay, the sterol extract showed significant hydroxyl radical scavenging in a dose-dependent manner (IC50 value 1.17 µg mL(-1)). Concentration of the sample required to reduce lipid peroxidation was found to be 4.18 µg mL(-1), and the extract also possessed acetylcholinesterase activity (IC50 - 5.26 µg mL(-1)). Catalase activity was 0.196 μM H2 O2 decomposed min(-1) µg(-1) protein, whereas the peroxidase activity was 17.01 μM of pyragallol oxidized min(-1) µg(-1) protein. The extract recorded higher activity against growth of S. greseus and C. albicans in the experiments carried out to determine antibacterial and antifungal activity, respectively. Copyright © 2012 John Wiley & Sons, Ltd.

  15. Anti-cholelithogenic potential of dietary spices and their bioactives.

    PubMed

    Srinivasan, Krishnapura

    2017-05-24

    Dietary hypocholesterolemic spices-curcumin (active compound of turmeric (Curcuma longa)) and capsaicin (active compound of red pepper (Capsicum annuum)), the active principles of spices-turmeric (Curcuma longa) and red pepper (Capsicum annuum), fenugreek (Trigonella foenum-graecum) seeds, garlic (Allium sativum), and onion (Allium cepa) are documented to have anti-cholelithogenic property in animal model. These spices prevent the induction of cholesterol gallstones by lithogenic high cholesterol diet and also regress the pre-established cholesterol gallstones, by virtue of their hypolipidemic potential. The antilithogenic influence of these spices is primarily attributable to their hypocholesterolemic effect. Increased cholesterol saturation index, cholesterol:phospholipid ratio and cholesterol:bile acid ratio in the bile caused by the lithogenic diet was countered by these spices. The antilithogenicity of these hypocholesterolemic spices was considered to be due also to their influence on biliary proteins that have pro-nucleating activity and anti-nucleating activity. Investigations on the involvement of biliary proteins in cholesterol crystal nucleation revealed that in an in vitro bile model, low molecular weight biliary proteins of the lithogenic diet fed animals have a pro-nucleating activity. On the contrary, low molecular weight biliary proteins of the animals fed hypocholesterolemic spices along with lithogenic diet showed a potent anti-nucleating activity.

  16. In Vitro Wound Healing Potential and Identification of Bioactive Compounds from Moringa oleifera Lam

    PubMed Central

    Muhammad, Abubakar Amali; Pauzi, Nur Aimi Syarina; Arulselvan, Palanisamy; Abas, Faridah; Fakurazi, Sharida

    2013-01-01

    Moringa oleifera Lam. (M. oleifera) from the monogeneric family Moringaceae is found in tropical and subtropical countries. The present study was aimed at exploring the in vitro wound healing potential of M. oleifera and identification of active compounds that may be responsible for its wound healing action. The study included cell viability, proliferation, and wound scratch test assays. Different solvent crude extracts were screened, and the most active crude extract was further subjected to differential bioguided fractionation. Fractions were also screened and most active aqueous fraction was finally obtained for further investigation. HPLC and LC-MS/MS analysis were used for identification and confirmation of bioactive compounds. The results of our study demonstrated that aqueous fraction of M. oleifera significantly enhanced proliferation and viability as well as migration of human dermal fibroblast (HDF) cells compared to the untreated control and other fractions. The HPLC and LC-MS/MS studies revealed kaempferol and quercetin compounds in the crude methanolic extract and a major bioactive compound Vicenin-2 was identified in the bioactive aqueous fraction which was confirmed with standard Vicenin-2 using HPLC and UV spectroscopic methods. These findings suggest that bioactive fraction of M. oleifera containing Vicenin-2 compound may enhance faster wound healing in vitro. PMID:24490175

  17. The potential of Ganoderma lucidum extracts as bioactive ingredients in topical formulations, beyond its nutritional benefits.

    PubMed

    Taofiq, Oludemi; Heleno, Sandrina A; Calhelha, Ricardo C; Alves, Maria José; Barros, Lillian; González-Paramás, Ana M; Barreiro, Maria F; Ferreira, Isabel C F R

    2017-10-01

    Ganoderma lucidum was characterized in terms of nutritional value and chemical composition. Thereafter, ethanolic Soxhlet extracts were evaluated for antioxidant, anti-inflammatory, antityrosinase, antimicrobial and cytotoxic effects, and further characterized in terms of phenolic acids, polysaccharides and triterpenoids. Finally, the obtained extracts were tested as cosmeceutical ingredients. G. lucidum proved to be a source of macronutrients and important bioactive compounds such as terpenoids, specially triterpenoids, and polysaccharides. In the extracts, ganoderic acids C2, A and H were the most abundant triterpenic acids and protocatechuic, p-hydroxibenzoic and syringic acids the identified phenolics. The developed cosmeceutical formulation preserved the extract bioactivities, presented a light-yellow colour and a pH of 4.6, which is considered appropriate for cosmeceutical's design. Behind the important nutritional/bioactive composition of G. lucidum, a potential towards its valorisation in the field of cosmeceuticals is foreseeable, as deduced from the bioactivities of its ethanolic extract and preservation in the tested formulation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Evaluation of the potential of squash pumpkin by-products (seeds and shell) as sources of antioxidant and bioactive compounds.

    PubMed

    Saavedra, M J; Aires, A; Dias, C; Almeida, J A; De Vasconcelos, M C B M; Santos, P; Rosa, E A

    2015-02-01

    The transformation of byproducts and wastes generated by agro-food companies is of high importance since only a small portion of plant material is utilized directly for human consumption. Squash pumpkin is greatly used in Portugal and as by-products of its processing are generated tons of shell and seeds. In this study we aim to evaluate the potential of these wastes as sources of beneficial and bioactive compounds (antioxidants and antimicrobials), studying the effect of different extraction solvents and drying methods. The samples (fresh and cooked) were freeze-dried and oven-dried followed by extraction with different solvents that revealed the following decreasing order of efficiency: 70 % ethanol, 70 % methanol, 70 % acetone, ultra-pure water and 100 % dichloromethane. The oven-dried samples showed higher values of antioxidant activity and phenolic content, with exception of the values of phenolics for the seeds material. The shell samples presented higher values (1.47 - 70.96 % inhibition) of antioxidant activity and total phenolic content (2.00 - 10.69 mg GAE/g DW). A positive correlation was found between these two parameters on the shell samples, however the squash seeds revealed a negative correlation between the phenolic content and the antioxidant activity. The results show that these industrial agro-food residues are potentially good sources of bioactive compounds with health benefits.

  19. "Potential health benefits of lunasin: a multifaceted soy-derived bioactive peptide".

    PubMed

    Lule, Vaibhao Kisanrao; Garg, Sheenam; Pophaly, Sarang Dilip; Hitesh; Tomar, Sudhir Kumar

    2015-03-01

    Bioactive peptides are small protein fragments derived from enzymatic hydrolysis of food proteins, fermentation with proteolytic starter cultures, and gastrointestinal digestion. These peptides have positive impacts on a number of physiological functions in living beings. Lunasin, a soy-derived bioactive peptide, is one of the most promising among them. Lunasin encoded within 2S albumin (GM2S-1) gene, identified as a novel peptide extracted from soybean seed. It is composed of 43 amino acid residues with a molecular weight of 5.5 kDa. Extensive scientific studies have shown that lunasin possesses inherent antioxidative, anti-inflammatory, anticancerous properties and could also play a vital role in regulating of cholesterol biosynthesis in the body. Its high bioavailability and heat stable nature allow its potential use as dietary supplement. The present review summarizes some of the potential health and therapeutic benefits of lunasin reported hitherto. © 2015 Institute of Food Technologists®

  20. Difluorocyclobutylacetylenes as positive allosteric modulators of mGluR5 with reduced bioactivation potential.

    PubMed

    Degnan, Andrew P; Maxwell, Darrell; Balakrishnan, Anand; Brown, Jeffrey M; Easton, Amy; Gulianello, Michael; Hanumegowda, Umesh; Hill-Drzewi, Melissa; Miller, Regina; Santone, Kenneth S; Senapati, Arun; Shields, Eric E; Sivarao, Digavalli V; Westphal, Ryan; Whiterock, Valerie J; Zhuo, Xiaoliang; Bronson, Joanne J; Macor, John E

    2016-12-15

    Schizophrenia is a serious illness that affects millions of patients and has been associated with N-methyl-d-aspartate receptor (NMDAR) hypofunction. It has been demonstrated that activation of metabotropic glutamate receptor 5 (mGluR5) enhances NMDA receptor function, suggesting the potential utility of mGluR5 positive allosteric modulators (PAMs) in the treatment of schizophrenia. Herein we describe the optimization of an mGluR5 PAM by replacement of a phenyl with aliphatic heterocycles and carbocycles as a strategy to reduce bioactivation in a biaryl acetylene chemotype. Replacement with a difluorocyclobutane followed by further optimization culminated in the identification of compound 32, a low fold shift PAM with reduced bioactivation potential. Compound 32 demonstrated favorable brain uptake and robust efficacy in mouse novel object recognition (NOR) at low doses.

  1. Hydroxyapatite-based materials of marine origin: a bioactivity and sintering study.

    PubMed

    Piccirillo, C; Pullar, R C; Costa, E; Santos-Silva, A; Pintado, M M E; Castro, P M L

    2015-06-01

    Single phase hydroxyapatite (HAp) and biphasic material hydroxyapatite/β-tricalcium phosphate (HAp/β-TCP) were obtained from a marine source (Atlantic cod fish bones). Here we report a study on the biological properties of these materials, including cytotoxicity, bioactivity and haemocompatibility. Results showed that the materials are not cytotoxic, neither in their powder nor in pellet form; indeed growth of Saos-2 cells was comparable to that of commercial. The haemolysis rate was lower than 2%; hence the materials can be classified as non-haemolytic. Moreover, when immersed in Simulated Body Fluid (SBF), crystal formation was observed on the surface of both materials. The sintering behaviour of the samples was also studied; both powders showed very high sinterability (density higher than 95% of the theoretical value). Overall, these results confirm the suitability of these materials for biomedical applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Potential role of bioactive peptides in prevention and treatment of chronic diseases: a narrative review.

    PubMed

    Cicero, Arrigo F G; Fogacci, Federica; Colletti, Alessandro

    2017-06-01

    In the past few years, increasing interest has been directed to bioactive peptides of animal and plant origin: in particular, researchers have focused their attention on their mechanisms of action and potential role in the prevention and treatment of cancer, cardiovascular and infective diseases. We have developed a search strategy to identify these studies in PubMed (January 1980 to May 2016); particularly those papers presenting comprehensive reviews or meta-analyses, plus in vitro and in vivo studies and clinical trials on those bioactive peptides that affect cardiovascular diseases, immunity or cancer, or have antioxidant, anti-inflammatory and antimicrobial effects. In this review we have mostly focused on evidence-based healthy properties of bioactive peptides from different sources. Bioactive peptides derived from fish, milk, meat and plants have demonstrated significant antihypertensive and lipid-lowering activity in clinical trials. Many bioactive peptides show selective cytotoxic activity against a wide range of cancer cell lines in vitro and in vivo, whereas others have immunomodulatory and antimicrobial effects. Furthermore, some peptides exert anti-inflammatory and antioxidant activity, which could aid in the prevention of chronic diseases. However, clinical evidence is at an early stage, and there is a need for solid pharmacokinetic data and for standardized extraction procedures. Further studies on animals and randomized clinical trials are required to confirm these effects, and enable these peptides to be used as preventive or therapeutic treatments. This article is part of a themed section on Principles of Pharmacological Research of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.11/issuetoc. © 2016 The British Pharmacological Society.

  3. Potential anticancer properties of bioactive compounds of Gymnema sylvestre and its biofunctionalized silver nanoparticles

    PubMed Central

    Arunachalam, Kantha Deivi; Arun, Lilly Baptista; Annamalai, Sathesh Kumar; Arunachalam, Aarrthy M

    2015-01-01

    Background Gymnema sylvestre is an ethno-pharmacologically important medicinal plant used in many polyherbal formulations for its potential health benefits. Silver nanoparticles (SNPs) were biofunctionalized using aqueous leaf extracts of G. sylvestre. The anticancer properties of the bioactive compounds and the biofunctionalized SNPs were compared using the HT29 human adenoma colon cancer cell line. Methods The preliminary phytochemical screening for bioactive compounds from aqueous extracts revealed the presence of alkaloids, triterpenes, flavonoids, steroids, and saponins. Biofunctionalized SNPs were synthesized using silver nitrate and characterized by ultraviolet–visible spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, and X-ray diffraction for size and shape. The characterized biofunctionalized G. sylvestre were tested for its in vitro anticancer activity against HT29 human colon adenocarcinoma cells. Results The biofunctionlized G. sylvestre SNPs showed the surface plasmon resonance band at 430 nm. The scanning electron microscopy images showed the presence of spherical nanoparticles of various sizes, which were further determined using the Scherrer equation. In vitro cytotoxic activity of the biofunctionalized green-synthesized SNPs (GSNPs) indicated that the sensitivity of HT29 human colon adenocarcinoma cells for cytotoxic drugs is higher than that of Vero cell line for the same cytotoxic agents and also higher than the bioactive compound of the aqueous extract. Conclusion Our results show that the anticancer properties of the bioactive compounds of G. sylvestre can be enhanced through biofunctionalizing the SNPs using the bioactive compounds present in the plant extract without compromising their medicinal properties. PMID:25565802

  4. The effect of plasma surface treatment on the bioactivity of titanium implant materials (in vitro).

    PubMed

    Abdelrahim, Ramy A; Badr, Nadia A; Baroudi, Kusai

    2016-01-01

    The surface of an implantable biomaterial plays a very important role in determining the biocompatibility, osteoinduction, and osteointegration of implants because it is in intimate contact with the host bone and soft tissues. This study was aimed to assess the effect of plasma surface treatment on the bioactivity of titanium alloy (Ti-6Al-4V). Fifteen titanium alloy samples were used in this study. The samples were divided into three groups (with five samples in each group). Five samples were kept untreated and served as control (group A). Another five plasma samples were sprayed for nitrogen ion implantation on their surfaces (group B) and the last five samples were pre-etched with acid before plasma treatment (group C). All the investigated samples were immersed for 7 days in Hank's balanced salt solution (HBSS) which was used as a simulating body fluid (SBF) at pH 7.4 and 37°C. HBSS was renewed every 3 days. The different surfaces were characterized by X-ray diffraction (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDXA), and Fourier Transformation Infrared Spectroscopy (FTIR). Nitriding of Ti-alloy samples via plasma nitrogen ion implantation increased the bioactivity of titanium. Moreover, the surface topography affected the chemical structure of the formed apatite. Increasing the surface roughness enhanced the bioactivity of the implant material. Nitridation can be exploited as an effective way to promote the formation of bone-like material on the implant surface.

  5. Structure and bioactivity studies of new polysiloxane-derived materials for orthopedic applications

    NASA Astrophysics Data System (ADS)

    Paluszkiewicz, Czesława; Gumuła, Teresa; Podporska, Joanna; Błażewicz, Marta

    2006-07-01

    The aim of this work was to examine the structure of new calcium silicate bioactive ceramic implant material for bone surgery applications. The bioceramic material was obtained by thermal treatment of active fillers-containing organosilicon polymer precursor. Different ceramic active fillers, namely Ca(OH) 2, CaCO 3, Na 2HPO 4 and SiO 2 powders were used. The phase composition of ceramic samples obtained by thermal transformation of active fillers containing polysiloxane was investigated. Morphology and structure of ceramic phases were characterized by means of scanning electron microscopy (SEM) with EDS point analysis, FTIR spectroscopy and XRD analysis. It was found that thermal treatment of active fillers-containing organosilicon precursor lead to the formation of wollastonite-containing ceramic material. This ceramic material showed bioactivity in 'in vitro' conditions studied by immersing the samples in simulated body fluid (SBF). The surface of wollastonite-containing ceramic before and after immersion in SBF was analysed. It can be concluded that this kind of ceramic material may be useful as bone substitute. FTIR spectroscopy is an adequate device for the determination of such derived materials structure.

  6. Synthesis of Bioactive Chlorogenic Acid-Silica Hybrid Materials via the Sol–Gel Route and Evaluation of Their Biocompatibility

    PubMed Central

    Pacifico, Severina

    2017-01-01

    Natural phenol compounds are gaining a great deal of attention because of their potential use as prophylactic and therapeutic agents in many diseases, as well as in applied science for their preventing role in oxidation deterioration. With the aim to synthetize new phenol-based materials, the sol–gel method was used to embed different content of the phenolic antioxidant chlorogenic acid (CGA) within silica matrices to obtain organic-inorganic hybrid materials. Fourier transform infrared (FTIR) measurements were used to characterize the prepared materials. The new materials were screened for their bioactivity and antioxidant potential. To this latter purpose, direct DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid) methods were applied: radical scavenging capability appeared strongly dependent on the phenol amount in investigated hybrids, and became pronounced, mainly toward the ABTS radical cation, when materials with CGA content equal to 15 wt% and 20 wt% were analyzed. The in vitro biocompatibility of the synthetized materials was estimated by using the MTT assay towards fibroblast NIH 3T3 cells, human keratinocyte HaCaT cells, and the neuroblastoma SH-SY5Y cell line. As cell viability and morphology of tested cell lines seemed to be unaffected by new materials, the attenuated total reflectance (ATR)-FTIR method was applied to deeply measure the effects of the hybrids in the three different cell lines. PMID:28773198

  7. Synthesis of Bioactive Chlorogenic Acid-Silica Hybrid Materials via the Sol-Gel Route and Evaluation of Their Biocompatibility.

    PubMed

    Catauro, Michelina; Pacifico, Severina

    2017-07-21

    Natural phenol compounds are gaining a great deal of attention because of their potential use as prophylactic and therapeutic agents in many diseases, as well as in applied science for their preventing role in oxidation deterioration. With the aim to synthetize new phenol-based materials, the sol-gel method was used to embed different content of the phenolic antioxidant chlorogenic acid (CGA) within silica matrices to obtain organic-inorganic hybrid materials. Fourier transform infrared (FTIR) measurements were used to characterize the prepared materials. The new materials were screened for their bioactivity and antioxidant potential. To this latter purpose, direct DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2'-azinobis-(3-ethylbenzothiazolin-6-sulfonic acid) methods were applied: radical scavenging capability appeared strongly dependent on the phenol amount in investigated hybrids, and became pronounced, mainly toward the ABTS radical cation, when materials with CGA content equal to 15 wt% and 20 wt% were analyzed. The in vitro biocompatibility of the synthetized materials was estimated by using the MTT assay towards fibroblast NIH 3T3 cells, human keratinocyte HaCaT cells, and the neuroblastoma SH-SY5Y cell line. As cell viability and morphology of tested cell lines seemed to be unaffected by new materials, the attenuated total reflectance (ATR)-FTIR method was applied to deeply measure the effects of the hybrids in the three different cell lines.

  8. Comparison of sealing ability of bioactive bone cement, mineral trioxide aggregate and Super EBA as furcation repair materials: A dye extraction study

    PubMed Central

    Balachandran, Janani; Gurucharan

    2013-01-01

    Context: Sealing ability of furcation repair material. Aims: To evaluate the sealing ability of bioactive bone cement, mineral trioxide aggregate (MTA) and Super Ethoxybenzoic Acid (EBA) as furcation repair materials in mandibular molars using a dye extraction leakage model. Settings and Design: In vitro, dye extraction study. Materials and Methods: Forty mandibular molars were randomly divided according to the material used to repair perforation: Group I-MTA, Group II-bioactive bone cement, Group III-Super EBA, Group IV-Control (furcation left unrepaired). All samples were subject to ortho grade and retrograde methylene blue dye challenge followed by dye extraction with 65% nitric acid. Samples were then analyzed using Ultra violet (UV) Visible Spectrophotometer. Statistical Analysis Used: One way analysis of variance (ANOVA), Tukey-Kramer Multiple Comparisons Test. Results: MTA and bioactive bone cement showed almost similar and lower absorbance values in comparison to Super EBA. Conclusions: Bioactive bone cement provi ded an excellent seal for furcal perforation repair and at the same time it provided comfortable handling properties, which could overcome the potential disadvantages as faced with MTA. PMID:23833460

  9. Genome mining reveals unlocked bioactive potential of marine Gram-negative bacteria.

    PubMed

    Machado, Henrique; Sonnenschein, Eva C; Melchiorsen, Jette; Gram, Lone

    2015-03-07

    Antibiotic resistance in bacteria spreads quickly, overtaking the pace at which new compounds are discovered and this emphasizes the immediate need to discover new compounds for control of infectious diseases. Terrestrial bacteria have for decades been investigated as a source of bioactive compounds leading to successful applications in pharmaceutical and biotech industries. Marine bacteria have so far not been exploited to the same extent; however, they are believed to harbor a multitude of novel bioactive chemistry. To explore this potential, genomes of 21 marine Alpha- and Gammaproteobacteria collected during the Galathea 3 expedition were sequenced and mined for natural product encoding gene clusters. Independently of genome size, bacteria of all tested genera carried a large number of clusters encoding different potential bioactivities, especially within the Vibrionaceae and Pseudoalteromonadaceae families. A very high potential was identified in pigmented pseudoalteromonads with up to 20 clusters in a single strain, mostly NRPSs and NRPS-PKS hybrids. Furthermore, regulatory elements in bioactivity-related pathways including chitin metabolism, quorum sensing and iron scavenging systems were investigated both in silico and in vitro. Genes with siderophore function were identified in 50% of the strains, however, all but one harboured the ferric-uptake-regulator gene. Genes encoding the syntethase of acylated homoserine lactones were found in Roseobacter-clade bacteria, but not in the Vibrionaceae strains and only in one Pseudoalteromonas strains. The understanding and manipulation of these elements can help in the discovery and production of new compounds never identified under regular laboratory cultivation conditions. High chitinolytic potential was demonstrated and verified for Vibrio and Pseudoalteromonas species that commonly live in close association with eukaryotic organisms in the environment. Chitin regulation by the ChiS histidine-kinase seems to be a

  10. Role of electrostatic potential in the in silico prediction of molecular bioactivation and mutagenesis.

    PubMed

    Ford, Kevin A

    2013-04-01

    Electrostatic potential (ESP) is a useful physicochemical property of a molecule that provides insights into inter- and intramolecular associations, as well as prediction of likely sites of electrophilic and nucleophilic metabolic attack. Knowledge of sites of metabolic attack is of paramount importance in DMPK research since drugs frequently fail in clinical trials due to the formation of bioactivated metabolites which are often difficult to measure experimentally due to their reactive nature and relatively short half-lives. Computational chemistry methods have proven invaluable in recent years as a means to predict and study bioactivated metabolites without the need for chemical syntheses, or testing on experimental animals. Additional molecular properties (heat of formation, heat of solvation and E(LUMO) - E(HOMO)) are discussed in this paper as complementary indicators of the behavior of metabolites in vivo. Five diverse examples are presented (acetaminophen, aniline/phenylamines, imidacloprid, nefazodone and vinyl chloride) which illustrate the utility of this multidimensional approach in predicting bioactivation, and in each case the predicted data agreed with experimental data described in the scientific literature. A further example of the usefulness of calculating ESP, in combination with the molecular properties mentioned above, is provided by an examination of the use of these parameters in providing an explanation for the sites of nucleophilic attack of the nucleic acid cytosine. Exploration of sites of nucleophilic attack of nucleic acids is important as adducts of DNA have the potential to result in mutagenesis.

  11. Bioactive peptides and depsipeptides with anticancer potential: sources from marine animals.

    PubMed

    Suarez-Jimenez, Guadalupe-Miroslava; Burgos-Hernandez, Armando; Ezquerra-Brauer, Josafat-Marina

    2012-05-01

    Biologically active compounds with different modes of action, such as, antiproliferative, antioxidant, antimicrotubule, have been isolated from marine sources, specifically algae and cyanobacteria. Recently research has been focused on peptides from marine animal sources, since they have been found as secondary metabolites from sponges, ascidians, tunicates, and mollusks. The structural characteristics of these peptides include various unusual amino acid residues which may be responsible for their bioactivity. Moreover, protein hydrolysates formed by the enzymatic digestion of aquatic and marine by-products are an important source of bioactive peptides. Purified peptides from these sources have been shown to have antioxidant activity and cytotoxic effect on several human cancer cell lines such as HeLa, AGS, and DLD-1. These characteristics imply that the use of peptides from marine sources has potential for the prevention and treatment of cancer, and that they might also be useful as molecular models in anticancer drug research. This review focuses on the latest studies and critical research in this field, and evidences the immense potential of marine animals as bioactive peptide sources.

  12. Bioactive Peptides and Depsipeptides with Anticancer Potential: Sources from Marine Animals

    PubMed Central

    Suarez-Jimenez, Guadalupe-Miroslava; Burgos-Hernandez, Armando; Ezquerra-Brauer, Josafat-Marina

    2012-01-01

    Biologically active compounds with different modes of action, such as, antiproliferative, antioxidant, antimicrotubule, have been isolated from marine sources, specifically algae and cyanobacteria. Recently research has been focused on peptides from marine animal sources, since they have been found as secondary metabolites from sponges, ascidians, tunicates, and mollusks. The structural characteristics of these peptides include various unusual amino acid residues which may be responsible for their bioactivity. Moreover, protein hydrolysates formed by the enzymatic digestion of aquatic and marine by-products are an important source of bioactive peptides. Purified peptides from these sources have been shown to have antioxidant activity and cytotoxic effect on several human cancer cell lines such as HeLa, AGS, and DLD-1. These characteristics imply that the use of peptides from marine sources has potential for the prevention and treatment of cancer, and that they might also be useful as molecular models in anticancer drug research. This review focuses on the latest studies and critical research in this field, and evidences the immense potential of marine animals as bioactive peptide sources. PMID:22822350

  13. Diversity and bioactive potentials of culturable heterotrophic bacteria from the surficial sediments of the Arabian Sea.

    PubMed

    Anas, Abdulaziz; Nilayangod, Charulatha; Jasmin, C; Vinothkumar, Saradavey; Parameswaran, P S; Nair, Shanta

    2016-12-01

    Marine sediments accommodate plethora of diverse microorganisms with varying ecological functions. In the present study, we isolated bacteria from surficial sediments of south east Arabian Sea (AS) and evaluated their bioactive potentials. A total of 131 isolates belonging to the phylum: γ-Proteobacteria (63%), Bacillales (34%) and Micrococcaceae (3%) were isolated. Among these, about 40% of the isolates showed the presence of secondary metabolite biosynthetic genes such as PKS or NRPS or both. Organic extracts of nearly 50% of these organisms were cytotoxic to human breast cancer MCF-7 cells and were bactericidal to human pathogens, Escherichia coli and Pseudomonas sp., while 20-30% of them were bactericidal to Vibrio sp. and Staphylococcus sp. too. In all, 8 isolates, belonging to Pseudomonas spp., Bacillus sp. and/or Lysinibacillus sp. displayed high level of bactericidal/cytotoxic properties. The study proposes AS sediment as a rich source for microorganisms with prospective bioactive molecules.

  14. Marine Bioactives as Functional Food Ingredients: Potential to Reduce the Incidence of Chronic Diseases

    PubMed Central

    Lordan, Sinéad; Ross, R. Paul; Stanton, Catherine

    2011-01-01

    The marine environment represents a relatively untapped source of functional ingredients that can be applied to various aspects of food processing, storage, and fortification. Moreover, numerous marine-based compounds have been identified as having diverse biological activities, with some reported to interfere with the pathogenesis of diseases. Bioactive peptides isolated from fish protein hydrolysates as well as algal fucans, galactans and alginates have been shown to possess anticoagulant, anticancer and hypocholesterolemic activities. Additionally, fish oils and marine bacteria are excellent sources of omega-3 fatty acids, while crustaceans and seaweeds contain powerful antioxidants such as carotenoids and phenolic compounds. On the basis of their bioactive properties, this review focuses on the potential use of marine-derived compounds as functional food ingredients for health maintenance and the prevention of chronic diseases. PMID:21747748

  15. Advance on the bioactivity and potential applications of dietary fibre from grape pomace.

    PubMed

    Zhu, Fengmei; Du, Bin; Zheng, Lihong; Li, Jun

    2015-11-01

    The winemaking grape pomaces are rich in bioactive phytochemicals and dietary fibre (DF). DFs are phenolic-rich DF matrix and are dietary supplement with benefits on human health. As a result of the increased attention to sustainability of winemaking by-products, efforts have been made to use grape pomace in different bio-industries. In this review, we summarize the existing knowledge on the bioactivity and potential applications of DF from grape pomace, as well as the chemical compositions of DF. Furthermore, the biological activities of DF such as, anti-cancer activity, antibacterial activity, anti-inflammatory activity, antioxidant activity, improving gastrointestinal health activity, anti-apoptotic activity, preventing cardiovascular disease activity, anti-hypercholesterolemic activity, are discussed. Finally, the possible applications and future prospects of grape pomace DF in various fields are also summarised.

  16. Marine bioactives as functional food ingredients: potential to reduce the incidence of chronic diseases.

    PubMed

    Lordan, Sinéad; Ross, R Paul; Stanton, Catherine

    2011-01-01

    The marine environment represents a relatively untapped source of functional ingredients that can be applied to various aspects of food processing, storage, and fortification. Moreover, numerous marine-based compounds have been identified as having diverse biological activities, with some reported to interfere with the pathogenesis of diseases. Bioactive peptides isolated from fish protein hydrolysates as well as algal fucans, galactans and alginates have been shown to possess anticoagulant, anticancer and hypocholesterolemic activities. Additionally, fish oils and marine bacteria are excellent sources of omega-3 fatty acids, while crustaceans and seaweeds contain powerful antioxidants such as carotenoids and phenolic compounds. On the basis of their bioactive properties, this review focuses on the potential use of marine-derived compounds as functional food ingredients for health maintenance and the prevention of chronic diseases.

  17. Bioactive glasses as accelerators of apatite bioactivity.

    PubMed

    Vallet-Regí, M; Rámila, A; Padilla, S; Muñoz, B

    2003-09-01

    Synthetic carbonatehydroxyapatite is the ceramic closest to the mineral component of human bone and seems, therefore, the optimum material to use in osseous implants. However, in vitro assays performed to determine its bioactivity have shown no positive results after 2 months of assay. With the aim of improving this bioactivity, a new biphasic material was synthesized composed mainly of synthetic carbonatehydroxyapatite and only 5% of a sol-gel bioactive glass. In vitro assays were assessed to determine the bioactive behavior of this new material and revealed that the addition of a minimal amount of bioactive glass is enough to induce bioactivity on synthetic carbonatehydroxyapatites.

  18. Main chain acid-degradable polymers for the delivery of bioactive materials

    DOEpatents

    Frechet, Jean M. J. [Oakland, CA; Standley, Stephany M [Evanston, IL; Jain, Rachna [Milpitas, CA; Lee, Cameron C [Cambridge, MA

    2012-03-20

    Novel main chain acid degradable polymer backbones and drug delivery systems comprised of materials capable of delivering bioactive materials to cells for use as vaccines or other therapeutic agents are described. The polymers are synthesized using monomers that contain acid-degradable linkages cleavable under mild acidic conditions. The main chain of the resulting polymers readily degrade into many small molecules at low pH, but remain relatively stable and intact at physiological pH. The new materials have the common characteristic of being able to degrade by acid hydrolysis under conditions commonly found within the endosomal or lysosomal compartments of cells thereby releasing their payload within the cell. The materials can also be used for the delivery of therapeutics to the acidic regions of tumors and other sites of inflammation.

  19. Preparation, bioactivity and mechanism of nano-hydroxyapatite/sodium alginate/chitosan bone repair material.

    PubMed

    Liao, Jianguo; Li, Yanqun; Li, Haiyan; Liu, Jingxian; Xie, Yufen; Wang, Jianping; Zhang, Yongxiang

    2017-08-11

    As the major inorganic component of natural bone, nano-hydroxyapatite (n-HA) on its own is limited in its use in bone repair, due to its brittleness. Chitosan (CS) and sodium alginate (SAL) are used to reduce its brittleness and tendency to degradation. However, the compressive strength of the composite is still low, and its biological performance needs further study. Nano-hydroxyapatite/sodium alginate/chitosan (n-HA/SAL/CS) composite was prepared via an in situ synthesis method. Further, we prepared the n-HA/SAL/CS self-setting bone repair material by mixing n-HA/SAL/CS powder with a curing liquid (20 wt.% citric acid). In addition, the in vitro bioactivity and cell cytotoxicity were also explored. Transmission electron microscopy photos revealed that the n-HA crystals were uniformly distributed throughout the polymer matrix. Infrared IR spectroscopy indicated that the HA interacted with the COO- of SAL and NH2- of CS. The compressive strength of the n-HA/SAL/CS bone cement was 34.3 MPa and matched the demands of weight-bearing bones. Soaking in vitro in simulated body fluid demonstrated that the composite material had reasonably good bioactivity, while cytotoxicity tests indicated that the n-HA/SAL/CS cement could promote cell proliferation and was biocompatible. Compressive strength of n-HA/SAL/CS can satisfy the needs of cancellous bone, and in vitro bioactivity and cytotoxicity tests results indicated that the n-HA/SAL/CS composite could act as an optimal bone repair material.

  20. The effect of plasma surface treatment on the bioactivity of titanium implant materials (in vitro)

    PubMed Central

    Abdelrahim, Ramy A.; Badr, Nadia A.; Baroudi, Kusai

    2016-01-01

    Background: The surface of an implantable biomaterial plays a very important role in determining the biocompatibility, osteoinduction, and osteointegration of implants because it is in intimate contact with the host bone and soft tissues. Objective: This study was aimed to assess the effect of plasma surface treatment on the bioactivity of titanium alloy (Ti–6Al–4V). Materials and Methods: Fifteen titanium alloy samples were used in this study. The samples were divided into three groups (with five samples in each group). Five samples were kept untreated and served as control (group A). Another five plasma samples were sprayed for nitrogen ion implantation on their surfaces (group B) and the last five samples were pre-etched with acid before plasma treatment (group C). All the investigated samples were immersed for 7 days in Hank's balanced salt solution (HBSS) which was used as a simulating body fluid (SBF) at pH 7.4 and 37°C. HBSS was renewed every 3 days. The different surfaces were characterized by X-ray diffraction (XRD), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDXA), and Fourier Transformation Infrared Spectroscopy (FTIR). Results: Nitriding of Ti-alloy samples via plasma nitrogen ion implantation increased the bioactivity of titanium. Moreover, the surface topography affected the chemical structure of the formed apatite. Increasing the surface roughness enhanced the bioactivity of the implant material. Conclusions: Nitridation can be exploited as an effective way to promote the formation of bone-like material on the implant surface. PMID:27011927

  1. Sustained prolonged topical delivery of bioactive human insulin for potential treatment of cutaneous wounds.

    PubMed

    Hrynyk, Michael; Martins-Green, Manuela; Barron, Annelise E; Neufeld, Ronald J

    2010-10-15

    Skin damaged by heat, radiation, or chemical exposure is difficult to treat and slow to heal. Indeed full restoration of the tissue is difficult to obtain. Sub-dermal insulin injection was recently shown to stimulate wound healing of the skin by accelerating wound closure, stimulating angiogenesis and inducing a regenerative process of healing. We have developed a topical delivery vehicle that is capable of releasing therapeutic levels of bioactive insulin for several weeks with the potential to stimulate and sustain healing. By encapsulating the crystalline form of insulin within poly(d,l-lactide-co-glycolide) microspheres, we succeeded in stabilizing and then releasing bioactive insulin for up to 25 days. To measure bioactivity we used Rat L6 myofibroblasts, stimulated them with this slow release insulin and determined activation of the receptors on the cell surface by quantifying AKT phosphorylation. There was only a minor and gradual decrease in AKT phosphorylation over time. To determine whether the slow release insulin could stimulate keratinocyte migration, wounding was simulated by scratching confluent cultures of human keratinocytes (HaCaT). Coverage of the scratch "wounds" was significantly faster in the presence of insulin released from microspheres than in the insulin-free control. Extended and sustained topical delivery of active insulin from a stable protein crystal-based reservoir shows promise in promoting tissue healing. Copyright 2010 Elsevier B.V. All rights reserved.

  2. Bioactive properties and potentials cosmeceutical applications of phlorotannins isolated from brown seaweeds: A review.

    PubMed

    Sanjeewa, Kalu Kapuge Asanka; Kim, Eun-A; Son, Kwang-Tae; Jeon, You-Jin

    2016-09-01

    Currently, natural ingredients are becoming more attractive for the industries such as functional food, nutraceuticals, cosmeceutical and pharmaceutical industries as people starting to believe naturally occurring compounds are safer to humans than artificial compounds. Seaweeds are one of the most interesting organisms found in oceans around the earth, which are carrying great ecological importance and contribute to increase the biodiversity of ecosystems where they were originated and habitat. Within last few decades, discovery of secondary metabolites with biological activities from seaweeds has been significantly increased. Further, the unique secondary metabolites isolated from seaweeds including polysaccharides, carotenoids and polyphenols possess range of bioactive properties that make them potential ingredient for many industrial applications. Among those groups of compounds phlorotannins isolated from brown seaweeds have shown interesting bioactive properties including anti-cancer, anti-inflammation, anti-oxidant, anti-allergic, anti-wrinkling and hair growth promotion properties. Moreover, these properties associated with phlorotannins make them an ideal compounds to use as a functional ingredient in cosmeceutical products. Up to now no report has been reviewed about discuss properties of phlorotannins related to the cosmeceutical application. In the present review primary attention is given to the collect scientific data published about bioactive properties of brown algal phlorotannins related to the cosmeceutical industry.

  3. Bioactive and yield potential of jelly palms (Butia odorata Barb. Rodr.).

    PubMed

    Beskow, Günter Timm; Hoffmann, Jessica Fernanda; Teixeira, Andrea Miranda; Fachinello, José Carlos; Chaves, Fábio Clasen; Rombaldi, Cesar Valmor

    2015-04-01

    In this descriptive study, Butia odorata genotypes were evaluated for yield, fruit number, pulp yield, bioactive content (including phenolic compounds, carotenoid, anthocyanin, L-ascorbic acid, and fibre content), antioxidant potential, and phenotypic characteristics. Genotype 117 was the highest yielding, with an estimated fruit yield of 22,000 kg ha(-1) and pulp yield of 12,000 kg ha(-1). On the other hand, the lowest yielding genotype, accession 49, showed an estimated fruit yield of 8400 kg ha(-1). Jelly palm fruit were generally rich in phenolic content (280.50-398.50 mg 100(-1)g), carotenoid content (2.80-4.08 mg 100 g(-1)), and L-ascorbic acid content (34.63-63.84 mg 100g(-1)). While the highest yielding genotype was not the richest in bioactive content, the lowest yielding genotype showed the highest l-ascorbic acid content. Although fruit yield and phytochemical composition are desirable attributes in jelly palm fruit, none of the genotypes evaluated showed high levels of both. Therefore, fruit yield and bioactive phytochemical content appear to be inversely proportional.

  4. Intertidal marine sediment harbours Actinobacteria with promising bioactive and biosynthetic potential.

    PubMed

    Jose, Polpass Arul; Jha, Bhavanath

    2017-08-30

    Actinobacteria are the major source of bioactive natural products that find their value in research and drug discovery programmes. Antimicrobial resistance and the resulting high demand for novel antibiotics underscore the need for exploring novel sources of these bacteria endowed with biosynthetic potential. Intertidal ecosystems endure regular periods of immersion and emersion, and represent an untapped source of Actinobacteria. In this study, we studied the diversity and biosynthetic potential of cultivable Actinobacteria from intertidal sediments of Diu Island in the Arabian Sea. A total of 148 Actinobacteria were selectively isolated using a stamping method with eight isolation media. Isolates were grouped into OTUs based on their 16S rRNA gene sequence, and categorized within actinobacterial families such as Glycomycetaceae, Micromonosporaceae, Nocardiaceae, Nocardiopsaceae, Pseudonocardiaceae, Streptomycetaceae, and Thermomonosporaceae. The biosynthetic potential of the Actinobacteria, necessary for secondary metabolite biosynthesis, was screened and confirmed by extensive fingerprinting approaches based on genes coding for polyketide synthases and nonribosomal peptide synthetases. The observed biosynthetic potential was correlated with the antibacterial activity exhibited by these isolates in laboratory conditions. Ultimately, the results demonstrate that intertidal sediment is a rich source of diverse cultivable Actinobacteria with high potential to synthesize novel bioactive compounds in their genomes.

  5. Bioactive magnetic nanoparticles of Fe-Ga synthesized by sol-gel for their potential use in hyperthermia treatment.

    PubMed

    Sánchez, J; Cortés-Hernández, D A; Escobedo-Bocardo, J C; Jasso-Terán, R A; Zugasti-Cruz, A

    2014-10-01

    Hyperthermia is one of the most recents therapies for cancer treatment using particles with nanometric size and appropriate magnetic properties for destroying cancer cells. Magnetic nanoparticles (MNP's) of Fe-Ga and synthesized using a polycondensation reaction by sol-gel method were obtained. MNP's of Fe(1.4)Ga(1.6)O(4) that possess an inverse spinel structure were identified by X-Ray Diffraction, Transmission Electron Microscopy, Scanning Electron Microscopy and Energy Dispersive Spectroscopy. The results showed that the MNP's are composed only by Fe, Ga and O and their size is between 15 and 20 nm. The magnetic properties measured by Vibration Sample Magnetometry demonstrated a saturation magnetization value of 37.5 emu/g. To induce the MNP's bioactivity, a biomimetic method was used which consisted in the immersion of MNP's in a Simulated Body Fluid (SBF) for different periods of time (7, 14 and 21 d) along with a wollastonite disk. The formation of a bioactive layer, which closely resembles that formed on the existing bioactive systems and with a Ca/P atomic ratio within a range of 1.37-1.73 was observed on the MNP's. Cytotoxicity of MNP's was evaluated by in vitro hemolysis testing using human red blood cells at concentrations between 0.25 and 6.0 mg/mL. It was found that the MNP's were not cytotoxic at none of the concentrations used. The results indicate that Fe-Ga MNP's are potential materials for cancer treatment of both hard and soft tissue by hyperthermia and drug carriers, among other applications.

  6. Therapeutic and nutraceutical potential of bioactive compounds extracted from fruit residues.

    PubMed

    Babbar, Neha; Oberoi, Harinder Singh; Sandhu, Simranjeet Kaur

    2015-01-01

    The growing interest in the substitution of synthetic food antioxidants by natural ones has fostered research in identifying new low-cost antioxidants having commercial potential. Fruits such as mango, banana, and those belonging to the citrus family leave behind a substantial amount of residues in the form of peels, pulp, seeds, and stones. Due to lack of infrastructure to handle a huge quantity of available biomass, lack of processing facilities, and high processing cost, these residues represent a major disposal problem, especially in developing countries. Because of the presence of phenolic compounds, which impart nutraceutical properties to fruit residues, such residues hold tremendous potential in food, pharmaceutical, and cosmetic industries. The biological properties such as anticarcinogenicity, antimutagenicity, antiallergenicity, and antiageing activity have been reported for both natural as well as synthetic antioxidants. Special attention is focused on extraction of bioactive compounds from inexpensive or residual sources. The purpose of this review is to characterize different phenolics present in the fruit residues, discuss the antioxidant potential of such residues and the assays used in determination of antioxidant properties, discuss various methods for efficient extraction of the bioactive compounds, and highlight the importance of fruit residues as potential nutraceutical resources and biopreservatives.

  7. Fish viscera protein hydrolysates: Production, potential applications and functional and bioactive properties.

    PubMed

    Villamil, Oscar; Váquiro, Henry; Solanilla, José F

    2017-06-01

    The aquaculture and fishery chain is an important part of the economy of many countries around the world; in recent years it has experienced significant growth that generates more and more quantities of waste, which are mostly discarded, impacting the environment, despite having a useful chemical composition in various industrial sectors. This article presents a review of the agroindustrial potential of fish wastes, especially viscera, as a source for obtaining native protein and hydrolysates, explaining their production process, chemical composition and functional and bioactive properties that are important to the agricultural, cosmetic, pharmaceutical, food and nutraceutical industry.

  8. Natural resins and bioactive natural products thereof as potential antimicrobial agents.

    PubMed

    Termentzi, Aikaterini; Fokialakis, Nikolas; Skaltsounis, Alexios Leandros

    2011-01-01

    Natural products and their derivatives have historically been invaluable as a source of therapeutic agents and have contributed to the discovery of antimicrobial agents. However, today with the development of drug-resistant strains, new scaffolds and new sources of bioactive compounds are needed. To this end, plant derived natural resins are reviewed for their potential application as antimicrobial agents. Natural gums, extracts of the whole resins, as well as specific extracts, fractions, essential oils and isolated compounds from the above resins are discussed in terms of their antifungal, antibacterial, and antiprotozoal activity.

  9. Antihistamine Effect of a Pure Bioactive Compound Isolated from Slug (Diplosolenodes occidentalis) Material

    PubMed Central

    Jacob, AS; Simon, OR; Wheatle, D; Ruddock, P; McCook, K

    2014-01-01

    ABSTRACT Objective: Folklore claims of the therapeutic effect of garden slug (Diplosolenodes occidentalis) extract used to relieve bronchoconstriction in asthmatic individuals were never validated scientifically. The aim of this study was to isolate the pure bioactive compound from slug extract causing this effect. Methods: The crude ground material was prepared in ethanol and after filtration, separation by flash column chromatography method was done. The structure was elucidated by data from hydrogen and carbon nuclear magnetic resonance (NMR) profiles. The bioactive compound was assessed for dose dependent response effects on guinea pig tracheal smooth muscle pre-contracted with histamine. Receptor specificity studies were done by using HTMT dimaleate (H1 agonist). The type of antagonism was also identified. Results: The pure component isolated from garden slug material was identified by spectral studies as glyceryl trilinolenate. It caused dose-dependent relaxation in guinea pig tracheal smooth muscle strips pre-contracted with histamine, it acted via H1 type receptors and showed non-competitive antagonism. Conclusion: Glyceryl trilinolenate produced dose-dependent relaxation in tracheal smooth muscle strips in the presence of the agonist histamine. Glyceryl trilinolenate displayed non-competitive antagonism at H1 receptors in the trachea. This agent was able to alleviate bronchoconstriction in individuals presenting with atopic asthma in rural agricultural areas in Jamaica (verbal communications). It is possible that glyceryl trilinolenate can be used therapeutically to produce tracheal smooth muscle relaxation in individuals presenting with atopic asthma. PMID:25781274

  10. Bioactive Potential of Actinomycetes from Less Explored Ecosystems against Mycobacterium tuberculosis and Other Nonmycobacterial Pathogens

    PubMed Central

    Venugopal, Gopikrishnan; Subramaniam, Balaji; Ramasamy, Balagurunathan

    2014-01-01

    Bioactive potential of actinomycetes isolated from certain less explored Indian ecosystems against Mycobacterium tuberculosis and other nonmycobacterial pathogens was investigated. Actinomycetes were isolated from the soil samples collected from desert, coffee plantation, rubber forest, and hill area and their cultural and micromorphological characteristics were studied. Crude extracts were prepared by agar surface fermentation and tested against M. tuberculosis isolates by luciferase reporter phage (LRP) assay at 100 µg/mL. Activity against nonmycobacterial pathogens was studied by agar plug method. Totally 54 purified cultures of actinomycetes including 43 Streptomyces and 11 non-Streptomyces were isolated. While screening for antitubercular activity, extracts of 39 actinomycetes showed activity against one or more M. tuberculosis isolates whereas 27 isolates exhibited antagonistic activity against nonmycobacterial pathogens. In particular crude extracts from sixteen actinomycete isolates inhibited all the three M. tuberculosis isolates tested. Findings of the present study concluded that less explored ecosystems investigated in this study are the potential resource for bioactive actinomycetes. Further purification and characterization of active molecule from the potential extracts will pave the way for determination of MIC, toxicity, and specificity studies. PMID:27437460

  11. Application of Bioactive Natural Materials-based Products on Five Women's Diseases

    PubMed Central

    Yi, Sun Shin; Hwang, Eunmi; Baek, Hye Kyung; Kim, Tae-Hee; Lee, Hae-Hyeog

    2015-01-01

    Women's health has been threatened by various diseases mainly including heart disease, breast cancer, osteoporosis, depression, and autoimmune disease. But development of medication for these diseases has been restricted by high development costs and low success rates. Herein the attempt to develop valid bioactive materials from a traditional natural material has been made. Resveratrol has been reported to be effective in treatment of breast cancer and heart disease. Goji berry has received attention as a natural based therapeutic material to treat a diabetes, cardiovascular disease, and osteoporosis. Leonurus family has been reported to be effective particularly in pregnant women due to high contents of vitamin as well as stimulation of uterine contraction. Annona family has effects such as anti-anxiety, anticonvulsant and recently it is proposed to be as a therapeutic material to cure depression based on its strong antidepressant effect. Shiraia bambusicola has been utilized to cure angiogenesis-related disease from ancient China and furthermore recently it was proved to be effective in rheumatoid arthritis. Getting an understanding of utilization of these traditional natural materials not only enhances the interest in development of therapeutic materials for preventing and treating various women's diseases, but also makes it possible to develop novel therapeutic materials. PMID:26793675

  12. Application of Bioactive Natural Materials-based Products on Five Women's Diseases.

    PubMed

    Yi, Sun Shin; Hwang, Eunmi; Baek, Hye Kyung; Kim, Tae-Hee; Lee, Hae-Hyeog; Jun, Hyun Sik; Kim, Sung-Jo

    2015-12-01

    Women's health has been threatened by various diseases mainly including heart disease, breast cancer, osteoporosis, depression, and autoimmune disease. But development of medication for these diseases has been restricted by high development costs and low success rates. Herein the attempt to develop valid bioactive materials from a traditional natural material has been made. Resveratrol has been reported to be effective in treatment of breast cancer and heart disease. Goji berry has received attention as a natural based therapeutic material to treat a diabetes, cardiovascular disease, and osteoporosis. Leonurus family has been reported to be effective particularly in pregnant women due to high contents of vitamin as well as stimulation of uterine contraction. Annona family has effects such as anti-anxiety, anticonvulsant and recently it is proposed to be as a therapeutic material to cure depression based on its strong antidepressant effect. Shiraia bambusicola has been utilized to cure angiogenesis-related disease from ancient China and furthermore recently it was proved to be effective in rheumatoid arthritis. Getting an understanding of utilization of these traditional natural materials not only enhances the interest in development of therapeutic materials for preventing and treating various women's diseases, but also makes it possible to develop novel therapeutic materials.

  13. Picocyanobacteria from a clade of marine Cyanobium revealed bioactive potential against microalgae, bacteria, and marine invertebrates.

    PubMed

    Costa, Maria Sofia; Costa, Margarida; Ramos, Vítor; Leão, Pedro N; Barreiro, Aldo; Vasconcelos, Vítor; Martins, Rosário

    2015-01-01

    The production of bioactive compounds either toxic or with pharmacological applications by cyanobacteria is well established. However, picoplanktonic forms within this group of organisms have rarely been studied in this context. In this study, the toxicological potential of picocyanobacteria from a clade of marine Cyanobium strains isolated from the Portuguese coast was examined using different biological models. First, strains were identified by applying morphological and molecular approaches and cultured under lab conditions. A crude extract and three fractions reflecting a preliminary segregation of lipophilic metabolites were tested for toxicity with the marine microalga Nannochloropsis sp., the bacteria Pseudomonas sp., the brine shrimp Artemia salina, and fertilized eggs of the sea urchin Paracentrotus lividus. No significant apparent adverse effects were noted against Artemia salina. However, significant adverse effects were found in all other assays, with an inhibition of Nannochloropsis sp. and Pseudomonas sp. growth and marked reduction in Paracentrotus lividus larvae length. The results obtained indicated that Cyanobium genus may serve as a potential source of interesting bioactive compounds and emphasize the importance of also studying smaller picoplanktonic fractions of marine cyanobacteria.

  14. Gastrointestinal Endogenous Protein-Derived Bioactive Peptides: An in Vitro Study of Their Gut Modulatory Potential.

    PubMed

    Dave, Lakshmi A; Hayes, Maria; Mora, Leticia; Montoya, Carlos A; Moughan, Paul J; Rutherfurd, Shane M

    2016-04-01

    A recently proposed paradigm suggests that, like their dietary counterparts, digestion of gastrointestinal endogenous proteins (GEP) may also produce bioactive peptides. With an aim to test this hypothesis, in vitro digests of four GEP namely; trypsin (TRYP), lysozyme (LYS), mucin (MUC), serum albumin (SA) and a dietary protein chicken albumin (CA) were screened for their angiotensin-I converting (ACE-I), renin, platelet-activating factor-acetylhydrolase (PAF-AH) and dipeptidyl peptidase-IV inhibitory (DPP-IV) and antioxidant potential following simulated in vitro gastrointestinal digestion. Further, the resultant small intestinal digests were enriched to obtain peptides between 3-10 kDa in size. All in vitro digests of the four GEP were found to inhibit ACE-I compared to the positive control captopril when assayed at a concentration of 1 mg/mL, while the LYS < 3-kDa permeate fraction inhibited renin by 40% (±1.79%). The LYS < 10-kDa fraction inhibited PAF-AH by 39% (±4.34%), and the SA < 3-kDa fraction inhibited DPP-IV by 45% (±1.24%). The MUC < 3-kDa fraction had an ABTS-inhibition antioxidant activity of 150 (±24.79) µM trolox equivalent and the LYS < 10-kDa fraction inhibited 2,2-Diphenyl-1-picrylhydrazyl (DPPH) by 54% (±1.62%). Moreover, over 190 peptide-sequences were identified from the bioactive GEP fractions. The findings of the present study indicate that GEP are a significant source of bioactive peptides which may influence gut function.

  15. Gastrointestinal Endogenous Protein-Derived Bioactive Peptides: An in Vitro Study of Their Gut Modulatory Potential

    PubMed Central

    Dave, Lakshmi A.; Hayes, Maria; Mora, Leticia; Montoya, Carlos A.; Moughan, Paul J.; Rutherfurd, Shane M.

    2016-01-01

    A recently proposed paradigm suggests that, like their dietary counterparts, digestion of gastrointestinal endogenous proteins (GEP) may also produce bioactive peptides. With an aim to test this hypothesis, in vitro digests of four GEP namely; trypsin (TRYP), lysozyme (LYS), mucin (MUC), serum albumin (SA) and a dietary protein chicken albumin (CA) were screened for their angiotensin-I converting (ACE-I), renin, platelet-activating factor-acetylhydrolase (PAF-AH) and dipeptidyl peptidase-IV inhibitory (DPP-IV) and antioxidant potential following simulated in vitro gastrointestinal digestion. Further, the resultant small intestinal digests were enriched to obtain peptides between 3–10 kDa in size. All in vitro digests of the four GEP were found to inhibit ACE-I compared to the positive control captopril when assayed at a concentration of 1 mg/mL, while the LYS < 3-kDa permeate fraction inhibited renin by 40% (±1.79%). The LYS < 10-kDa fraction inhibited PAF-AH by 39% (±4.34%), and the SA < 3-kDa fraction inhibited DPP-IV by 45% (±1.24%). The MUC < 3-kDa fraction had an ABTS-inhibition antioxidant activity of 150 (±24.79) µM trolox equivalent and the LYS < 10-kDa fraction inhibited 2,2-Diphenyl-1-picrylhydrazyl (DPPH) by 54% (±1.62%). Moreover, over 190 peptide-sequences were identified from the bioactive GEP fractions. The findings of the present study indicate that GEP are a significant source of bioactive peptides which may influence gut function. PMID:27043546

  16. SAR analysis and bioactive potentials of freshwater and terrestrial cyanobacterial compounds: a review.

    PubMed

    Nagarajan, M; Maruthanayagam, V; Sundararaman, M

    2013-05-01

    Freshwater and terrestrial cyanobacteria resemble the marine forms in producing divergent chemicals such as linear, cyclic and azole containing peptides, alkaloids, cyclophanes, terpenes, lactones, etc. These metabolites have wider biomedical potentials in targeting proteases, cancers, parasites, pathogens and other cyanobacteria and algae (allelopathy). Among the various families of non-marine cyanobacterial peptides reported, many of them are acting as serine protease inhibitors. While the micropeptin family has a preference for chymotrypsin inhibition rather than other serine proteases, the aeruginosin family targets trypsin and thrombin. In addition, cyanobacterial compounds such as scytonemide A, lyngbyazothrins C and D and cylindrocyclophanes were found to inhibit 20S proteosome. Apart from proteases, metabolites blocking the other targets of cancer pathways may exhibit cytotoxic effect. Colon and rectum, breast, lung and prostate are the worst affecting cancers in humans and are deduced to be inhibited by both peptidic and non-peptidic compounds. Moreover, the growth of infections causing parasites such as Plasmodium, Leishmania and Trypanosoma are well controlled by peptides: aerucyclamides A-D, tychonamides and alkaloids: nostocarboline and calothrixins. Likewise, varieties of cyanobacterial compounds tend to inhibit serious infectious disease causing bacterial, fungal and viral agents. Interestingly, portoamides, spiroidesin, nostocyclamide and kasumigamide are the allelopathic peptides determined to suppress the growth of toxic cyanobacteria and nuisance algae. Thus cyanobacterial compounds have a broad bioactive spectrum; the analysis of SAR studies will not only assist to find out the mode of action but also reveal bioactive key components. Thereby, developing the drugs bearing these bioactive skeletons to treat various illnesses is wide open.

  17. Hierarchical bioactive materials for tissue reconstruction: Integrated design and manufacturing challenges

    NASA Astrophysics Data System (ADS)

    Hollister, Scott J.

    2011-04-01

    Although the paradigm shift from synthetic implants and tissue grafts to regenerative-medicine-based tissue reconstruction has been promised for well over a decade, the reality has yet to emerge. A significant reason for this delay is that regenerative medicine reconstruction solutions involve complex systems in which bioresorbable materials are integrated with surface modifications delivering cells and growth factors. These systems must not only fill complex shapes and provide temporary mechanical function; they must deliver biologic factors that stimulate tissue growth in a controlled, safe, yet rapid manner. Finally, the materials should degrade on a timeline matched to the time it takes to grow tissues. As such, these material device systems are multifunctional and require design techniques that can address multifunctionality, coupled with multiple material manufacturing processes that can be integrated to achieve the design. In this paper, we review these design and manufacturing processes as well as the challenges to integrate these multiple design and manufacturing processes to engineer bioactive material devices.

  18. Biodiversity, bioactive natural products and biotechnological potential of plant-associated endophytic actinobacteria.

    PubMed

    Qin, Sheng; Xing, Ke; Jiang, Ji-Hong; Xu, Li-Hua; Li, Wen-Jun

    2011-02-01

    Endophytic actinobacteria, which exist in the inner tissues of living plants, have attracted increasing attention among taxonomists, ecologists, agronomists, chemists and evolutionary biologists. Numerous studies have indicated that these prolific actinobacteria appear to have a capacity to produce an impressive array of secondary metabolites exhibiting a wide variety of biological activity, such as antibiotics, antitumor and anti-infection agents, plant growth promoters and enzymes, and may contribute to their host plants by promoting growth and enhancing their ability of withstanding the environmental stresses. These microorganisms may represent an underexplored reservoir of novel species of potential interest in the discovery of novel lead compounds and for exploitation in pharmaceutical, agriculture and industry. This review focuses on new findings in the isolation methods, bio- and chemical diversity of endophytic actinobacteria and reveals the potential biotechnological application. The facing problems and strategies for biodiversity research and bioactive natural products producing are also discussed.

  19. Biological Potential of Extraterrestrial Materials

    NASA Astrophysics Data System (ADS)

    Mautner, Michael N.; Conner, Anthony J.; Killham, Kenneth; Deamer, David W.

    1997-09-01

    Meteoritic materials are investigated as potential early planetary nutrients. Aqueous extracts of the Murchison C2 carbonaceous meteorite are utilized as a sole carbon source by microorganisms, as demonstrated by the genetically modifiedPseudomonas fluorescenceequipped with theluxgene. Nutrient effects are observed also with the soil microorganismsNocardia asteroidesandArthrobacter pascensthat reach populations up to 5 × 107CFU/ml in meteorite extracts, similar to populations in terrestrial soil extracts. Plant tissue cultures ofAsparagus officinalisandSolanum tuberosum(potato) exhibit enhanced pigmentation and some enhanced growth when meteorite extracts are added to partial nutrient media, but inhibited growth when added to full nutrient solution. The meteorite extracts lead to large increases in S, Ca, Mg, and Fe plant tissue contents as shown by X-ray fluorescence, while P, K, and Cl contents show mixed effects. In both microbiological and plant tissue experiments, the nutrient and inhibitory effects appear to be best balanced for growth at about 1:20 (extracted solid:H2O) ratios. The results suggest that solutions in cavities in meteorites can provide efficient concentrated biogenic and early nutrient environments, including high phosphate levels, which may be the limiting nutrient. The results also suggest that carbonaceous asteroid resources can sustain soil microbial activity and provide essential macronutrients for future space-based eco- systems.

  20. Bioactive peptides and hydrolysates from pulses and their potential use as functional ingredients.

    PubMed

    López-Barrios, Lidia; Gutiérrez-Uribe, Janet A; Serna-Saldívar, Sergio O

    2014-03-01

    Bioactive peptides (BPs) are amino acid sequences derived from food proteins. Their relevance lies in the biological activities they have once they are released from the parent protein. BPs or protein hydrolysates can be commercialized as nutraceutical products or functional ingredients according to their activities. Different food protein sources have been researched for their potential to generate BPs. However, with the exception of lunasin (derived from soy), animal protein sources have been predominantly exploited as commercial BPs sources. On the other hand, pulses have shown diverse BP contents without further impact on their commercialization. Pulses are a rich source of protein in the human diet and their consumption has been associated with the prevention of chronic diseases. The beneficial effect in human health has been related to their micronutrients, phytochemical bioactive compounds, and recently BPs. This article reviews the current literature about pulse protein hydrolysates and BPs with proved angiotensin converting enzyme inhibitory, antioxidant, cancer preventing, and other health promoting activities. Proteolysis process is commonly achieved by digestive and microorganism enzymes. BP purification and identification has consisted mainly on size segregation procedures followed by mass spectrometry techniques. Hydrolysis time, peptide size, and hydrophobicity are employed as process variants and structural features relevant for the BP activities. Finally, some considerations about industrial processing and BPs used as functional food ingredients were reviewed. © 2014 Institute of Food Technologists®

  1. Bioactive natural constituents from food sources-potential use in hypertension prevention and treatment.

    PubMed

    Huang, Wu-Yang; Davidge, Sandra T; Wu, Jianping

    2013-01-01

    Prevention and management of hypertension are the major public health challenges worldwide. Uncontrolled high blood pressure may lead to a shortened life expectancy and a higher morbidity due to a high risk of cardiovascular complications such as coronary heart disease (which leads to heart attack) and stroke, congestive heart failure, heart rhythm irregularities, and kidney failure etc. In recent years, it has been recognized that many dietary constituents may contribute to human cardiovascular health. There has been an increased focus on identifying these natural components of foods, describing their physiological activities and mechanisms of actions. Grain, vegetables, fruits, milk, cheese, meat, chicken, egg, fish, soybean, tea, wine, mushrooms, and lactic acid bacteria are various food sources with potential antihypertensive effects. Their main bioactive constituents include angiotensin I-converting enzyme (ACE) inhibitory peptides, vitamins C and E, flavonoids, flavanols, cathecins, anthocyanins, phenolic acids, polyphenols, tannins, resveratrol, polysaccharides, fiber, saponin, sterols, as well as K, Ca, and P. They may reduce blood pressure by different mechanisms, such as ACE inhibition effect, antioxidant, vasodilatory, opiate-like, Ca(2+) channel blocking, and chymase inhibitory activities. These functional foods may provide new therapeutic applications for hypertension prevention and treatment, and contribute to a healthy cardiovascular population. The present review summarizes the antihypertensive food sources and their bioactive constituents, as well as physiological mechanisms of dietary products, especially focusing on ACE inhibitory activity.

  2. Physical Stability of Octenyl Succinate-Modified Polysaccharides and Whey Proteins for Potential Use as Bioactive Carriers in Food Systems.

    PubMed

    Puerta-Gomez, Alex F; Castell-Perez, M Elena

    2015-06-01

    The high cost and potential toxicity of biodegradable polymers like poly(lactic-co-glycolic)acid (PLGA) has increased the interest in natural and modified biopolymers as bioactive carriers. This study characterized the physical stability (water sorption and state transition behavior) of selected starch and proteins: octenyl succinate-modified depolymerized waxy corn starch (DWxCn), waxy rice starch (DWxRc), phytoglycogen, whey protein concentrate (80%, WPC), whey protein isolate (WPI), and α-lactalbumin (α-L) to determine their potential as carriers of bioactive compounds under different environmental conditions. After enzyme modification and particle size characterization, glass transition temperature and moisture isotherms were used to characterize the systems. DWxCn and DWxRc had increased water sorption compared to native starch. The level of octenyl succinate anhydrate (OSA) modification (3% and 7%) did not reduce the water sorption of the DWxCn and phytoglycogen samples. The Guggenheim-Andersen-de Boer model indicated that native waxy corn had significantly (P < 0.05) higher water monolayer capacity followed by 3%-OSA-modified DWxCn, WPI, 3%-OSA-modified DWxRc, α-L, and native phytoglycogen. WPC had significantly lower water monolayer capacity. All Tg values matched with the solid-like appearance of the biopolymers. Native polysaccharides and whey proteins had higher glass transition temperature (Tg) values. On the other hand, depolymerized waxy starches at 7%-OSA modification had a "melted" appearance when exposed to environments with high relative humidity (above 70%) after 10 days at 23 °C. The use of depolymerized and OSA-modified polysaccharides blended with proteins created more stable blends of biopolymers. Hence, this biopolymer would be suitable for materials exposed to high humidity environments in food applications.

  3. Opportunistic in vitro spontaneous generation of bioactive material via longitudinal coupling electrostatic discharge during cell sorting

    SciTech Connect

    Durack, G.; Kelley, S.; Ragheb, K.; Lawler, G.; Robinson, J.P. )

    1993-01-01

    It has previously been reported by numerous, investigators and therefore generally accepted, that at sample flow rates greater than 2,000 cells per second a sorting purity of 100% cannot achieved for sorts lasting 2 hours or more. The authors have developed a theoretical model, based on Maxwell's electromagnetic equations and basic quantum mechanics as applied to a Newtonian frame of reference, which explains to their satisfaction this phenomenon. Basically, as charged droplets containing cells selected for sorting are accelerated through the varying density electromagnetic field produced by the sorting plates, there is a 0.1% probability that a high energy gamma particle will strike the ground plane of the flow cytometer. If this occurs while the instantaneous acceleration of the cell in the droplet is less than 9.74 m/s[sup 2] the alpha particles scattered tangentially from the ground plane can be longitudinally coupled to the volume immediately surrounding the cell encased by the droplet. The radius of curvature of the droplet is such that the resulting bio-radiation undergoes total internal reflection (TIR) which effectively produces a pseudo-bireactive Dirac function. A Hilbert transform of this function clearly indicates that all possible solutions that balance this function can only be obtained if there is additional bioactive material present within droplet radius. Subsequent testing has repeatedly shown that in fact most of what was erroneously thought to be contamination during sorting can be explained through application of this theory. Further investigation is expected to lead to classification of this bioactive material as an other life form.

  4. Novel bioactive materials developed by simulated body fluid evaluation: Surface-modified Ti metal and its alloys.

    PubMed

    Kokubo, Tadashi; Yamaguchi, Seiji

    2016-10-15

    Until the discovery of the bone-bonding activity of Bioglass by Hench et al. in the early 1970s, it had not been demonstrated that a synthetic material could bond to living bone without eliciting a foreign body reaction. Since then, various kinds of materials based on calcium phosphate, such as sintered hydroxyapatite and β-tricalcium phosphate have also been shown to bond to living bone. Until the discovery of the bone-bonding activity of Ti metal formed with a sodium titanate surface layer by the present authors in 1996, it had not been shown that a metallic material could bond to living bone. Since then, various kinds of surface-modified Ti metal and its alloys have been found to bond to living bone. Until the discovery of the osteoinduction of porous hydroxyapatite by Yamasaki in 1990, it was unknown whether a synthetic material could induce bone formation even in muscle tissue. Since then, various kinds of porous calcium phosphate ceramics have been shown to induce osteoinduction. Until the discovery of osteoinduction induced by a porous Ti metal formed with a titanium oxide surface layer by Fujibayashi et al. in 2004, it had been unclear whether porous metals would be able to induce osteoinduction. These novel bioactive materials have been developed by systematic research into the apatite formation that occurs on surface-modified Ti metal and its related materials in an acellular simulated body fluid (SBF) having ion concentrations almost equal to those of human blood plasma. Some of the novel bioactive materials based on Ti metal are already in clinical use or clinical trials, such as artificial hip joints and spinal fusion devices. In the present paper, we review how these novel bioactive materials based on Ti metal have been developed based on an evaluation of apatite formation in SBF. Without the SBF evaluation, these novel bioactive materials would most likely never have been developed. On the basis of systematic study of apatite formation on a material

  5. Biological and bactericidal properties of Ag-doped bioactive glass in a natural extracellular matrix hydrogel with potential application in dentistry.

    PubMed

    Wang, Y-Y; Chatzistavrou, X; Faulk, D; Badylak, S; Zheng, L; Papagerakis, S; Ge, L; Liu, H; Papagerakis, P

    2015-06-20

    The aim of this study was the fabrication and evaluation of a novel bioactive and bactericidal material, which could have applications in dentistry by supporting tissue regeneration and killing oral bacteria. Our hypothesis was that a new scaffold for pulp-dentin tissue engineering with enhanced antibacterial activity could be obtained by associating extracellular matrix derived from porcine bladder with an antibacterial bioactive glass. Our study combines in vitro approaches and ectopic implantation in scid mice. The novel material was fabricated by incorporating a sol-gel derived silver (Ag)-doped bioactive glass (BG) in a natural extracellular matrix (ECM) hydrogel in ratio 1:1 in weight % (Ag-BG/ECM). The biological properties of the Ag-BG/ECM were evaluated in culture with dental pulp stem cells (DPSCs). In particular, cell proliferation, cell apoptosis, stem cells markers profile, and cell differentiation potential were studied. Furthermore, the antibacterial activity against Streptococcus mutans and Lactobacillus casei was measured. Moreover, the capability of the material to enhance pulp/dentin regeneration in vivo was also evaluated. Our data show that Ag-BG/ECM significantly enhances DPSCs' proliferation, it does not affect cell morphology and stem cells markers profile, protects cells from apoptosis, and enhances in vitro cell differentiation and mineralisation potential as well as in vivo dentin formation. Furthermore, Ag-BG/ECM strongly inhibits S. mutans and L. casei growth suggesting that the new material has also anti-bacterial properties. This study provides foundation for future clinical applications in dentistry. It could potentially advance the currently available options of dental regenerative materials.

  6. Potential Benefits of Jujube (Zizyphus Lotus L.) Bioactive Compounds for Nutrition and Health

    PubMed Central

    2016-01-01

    Zizyphus lotus, belonging to the Rhamnaceae family, is a deciduous shrub which generally grows in arid and semiarid regions of the globe. In traditional medicine, Z. lotus is used as antidiabetes, sedative, bronchitis, and antidiarrhea by local populations. Recently, several scientific reports for health benefit and nutritional potential of bioactive compounds from this jujube have been reported. This plant is rich in polyphenols, cyclopeptide alkaloids, dammarane saponins, vitamins, minerals, amino acids, and polyunsaturated fatty acids. These identified compounds were supposed to be responsible for most of Z. lotus biologically relevant activities including antimicrobial, anti-inflammatory, hypoglycemic, antioxidant, and immunomodulatory effects. The aim of the present review was to give particular emphasis on the most recent findings on biological effects of the major groups of Zizyphus lotus components and their medical interest, notably for human nutrition, health benefit, and therapeutic impacts. PMID:28053781

  7. Food protein-derived bioactive peptides: production, processing, and potential health benefits.

    PubMed

    Udenigwe, Chibuike C; Aluko, Rotimi E

    2012-01-01

    Bioactive peptides (BAPs), derived through enzymatic hydrolysis of food proteins, have demonstrated potential for application as health-promoting agents against numerous human health and disease conditions, including cardiovascular disease, inflammation, and cancer. The feasibility of pharmacological application of these peptides depends on absorption and bioavailability in intact forms in target tissues, which in turn depends on structure of the peptides. Therefore, production and processing of peptides based on important structure-function parameters can lead to the production of potent peptides. This article reviews the literature on BAPs with emphasis on strategic production and processing methods as well as antihypertensive, anticancer, anticalmodulin, hypocholesterolemic, and multifunctional properties of the food protein-derived peptides. It is recommended that future research efforts on BAP should be directed toward elucidation of their in vivo molecular mechanisms of action, safety at various doses, and pharmacological activity in maintaining homeostasis during aberrant health conditions in human subjects. © 2011 Institute of Food Technologists®

  8. New organoruthenium complexes with bioactive thiosemicarbazones as co-ligands: potential anti-trypanosomal agents†

    PubMed Central

    Demoro, Bruno; Sarniguet, Cynthia; Sánchez-Delgado, Roberto; Rossi, Miriam; Liebowitz, Daniel; Caruso, Francesco; Olea-Azar, Claudio; Moreno, Virtudes; Medeiros, Andrea; Comini, Marcelo A.; Otero, Lucía; Gambino, Dinorah

    2012-01-01

    In the search for new therapeutic tools against neglected diseases produced by trypanosomatid parasites, and particularly against African Trypanosomiasis, whose etiological agent is Trypanosoma brucei, organoruthenium compounds with bioactive nitrofuran containing thiosemicarbazones (L) as co-ligands were obtained. Four ruthenium(ii) complexes with the formula [Ru2(p-cymene)2(L)2]X2, where X = Cl or PF6, were synthesized and the crystal structures of two of them were solved by X-ray diffraction methods. Two of the complexes show significant in vitro growth inhibition activity against Trypanosoma brucei brucei and are highly selective towards trypanosomal cells with respect to mammalian cells (J774 murine macrophages). These promising results make the title organoruthenium compounds good lead candidates for further developments towards potential antitrypanosomal organometallic drugs. PMID:22138896

  9. Molecular Regulation of Adipogenesis and Potential Anti-Adipogenic Bioactive Molecules

    PubMed Central

    Moseti, Dorothy; Regassa, Alemu; Kim, Woo-Kyun

    2016-01-01

    Adipogenesis is the process by which precursor stem cells differentiate into lipid laden adipocytes. Adipogenesis is regulated by a complex and highly orchestrated gene expression program. In mammalian cells, the peroxisome proliferator-activated receptor γ (PPARγ), and the CCAAT/enhancer binding proteins (C/EBPs) such as C/EBPα, β and δ are considered the key early regulators of adipogenesis, while fatty acid binding protein 4 (FABP4), adiponectin, and fatty acid synthase (FAS) are responsible for the formation of mature adipocytes. Excess accumulation of lipids in the adipose tissue leads to obesity, which is associated with cardiovascular diseases, type II diabetes and other pathologies. Thus, investigating adipose tissue development and the underlying molecular mechanisms is vital to develop therapeutic agents capable of curbing the increasing incidence of obesity and related pathologies. In this review, we address the process of adipogenic differentiation, key transcription factors and proteins involved, adipogenic regulators and potential anti-adipogenic bioactive molecules. PMID:26797605

  10. Cocoa Bioactive Compounds: Significance and Potential for the Maintenance of Skin Health

    PubMed Central

    Scapagnini, Giovanni; Davinelli, Sergio; Di Renzo, Laura; De Lorenzo, Antonino; Olarte, Hector Hugo; Micali, Giuseppe; Cicero, Arrigo F.; Gonzalez, Salvador

    2014-01-01

    Cocoa has a rich history in human use. Skin is prone to the development of several diseases, and the mechanisms in the pathogenesis of aged skin are still poorly understood. However, a growing body of evidence from clinical and bench research has begun to provide scientific validation for the use of cocoa-derived phytochemicals as an effective approach for skin protection. Although the specific molecular and cellular mechanisms of the beneficial actions of cocoa phytochemicals remain to be elucidated, this review will provide an overview of the current literature emphasizing potential cytoprotective pathways modulated by cocoa and its polyphenolic components. Moreover, we will summarize in vivo studies showing that bioactive compounds of cocoa may have a positive impact on skin health. PMID:25116848

  11. Cocoa bioactive compounds: significance and potential for the maintenance of skin health.

    PubMed

    Scapagnini, Giovanni; Davinelli, Sergio; Di Renzo, Laura; De Lorenzo, Antonino; Olarte, Hector Hugo; Micali, Giuseppe; Cicero, Arrigo F; Gonzalez, Salvador

    2014-08-11

    Cocoa has a rich history in human use. Skin is prone to the development of several diseases, and the mechanisms in the pathogenesis of aged skin are still poorly understood. However, a growing body of evidence from clinical and bench research has begun to provide scientific validation for the use of cocoa-derived phytochemicals as an effective approach for skin protection. Although the specific molecular and cellular mechanisms of the beneficial actions of cocoa phytochemicals remain to be elucidated, this review will provide an overview of the current literature emphasizing potential cytoprotective pathways modulated by cocoa and its polyphenolic components. Moreover, we will summarize in vivo studies showing that bioactive compounds of cocoa may have a positive impact on skin health.

  12. Thermogelling chitosan-collagen-bioactive glass nanoparticle hybrids as potential injectable systems for tissue engineering.

    PubMed

    Moreira, Cheisy D F; Carvalho, Sandhra M; Mansur, Herman S; Pereira, Marivalda M

    2016-01-01

    Recently, stimuli-responsive nanocomposite-derived hydrogels have gained prominence in tissue engineering because they can be applied as injectable scaffolds in bone and cartilage repair. Due to the great potential of these systems, this study aimed to synthesize and characterize novel thermosensitive chitosan-based composites, chemically modified with collagen and reinforced by bioactive glass nanoparticles (BG) on the development of injectable nanohybrids for regenerative medicine applications. Thus, the composite hydrogels were extensively characterized by structural, morphological, rheological, and biological testing. The composites showed thermosensitive response with the gelation temperature at approximately 37 °C, which is compatible with the human body temperature. In addition, scanning electron microscopy (SEM) analysis indicated that the chitosan hydrogels exhibited 3D-porous structures, and the incorporation of collagen in the system caused increase on the average pore size. Fourier transform infrared spectroscopy (FTIR) analysis indicated the main functional groups of each component of the composite system and their chemical interactions forming the scaffold. Moreover, rheological measurements were employed to assess the viscoelastic behavior of the hydrogels as a function of the temperature. The results demonstrated that the addition of collagen and bioactive glass increases the mechanical properties after the gelation process. The addition of 2 wt.% of BG nanoparticles caused an increase of approximately 39% on stiffness compared to pure chitosan and the addition of 30 wt.% collagen caused a further increase on the stiffness by 95%. The cytotoxicity and cell viability of the hydrogels were assessed by MTT and LIVE/DEAD® assays, where the results demonstrated no toxic effect of the composites on the human osteosarcoma cell culture (SAOS) and kidney cells line of human embryo (HEK 293 T). Hence, it can be stated that innovative composites were

  13. The Immunomodulatory Potential of Selected Bioactive Plant-Based Compounds in Breast Cancer: A Review.

    PubMed

    Baraya, Yusha U Shu Aibu; Wong, Kah Keng; Yaacob, Nik Soriani

    2016-08-17

    Breast cancer has continued to cause high cancer death rates among women worldwide. The use of plants' natural products in breast cancer treatment has received more attention in recent years due to their potentially wider safety margin and the potential to complement conventional chemotherapeutic drugs. Plant-based products have demonstrated anticancer potential through different biological pathways including modulation of the immune system. Immunomodulatory properties of medicinal plants have been shown to mitigate breast cancer cell growth. Different immune cell types participate in this process especially cytotoxic T cells and natural killer cells, and cytokines including chemokines and tumor necrosis factor-α. Medicinal plants such as Glycyrrhiza glabra, Uncaria tomentosa, Camellia sinensis, Panax ginseng, Prunus armenaica (apricot), Allium sativum, Arctium lappa and Curcuma longa were reported to hold strong potential in breast cancer treatment in various parts of the world. Interestingly, research findings have shown that these plants possess bioactive immunomodulators as their main constituents producing the anticancer effects. These immunomodulatory compounds include ajoene, arctigenin, β-carotene, curcumin, epigallocatechin-3-gallate, ginsan, glabridin and quinic acid. In this review, we discussed the ability of these eight immunomodulators in regulating the immune system potentially applicable in breast cancer treatment via anti-inflammatory (curcumin, arctigenin, glabridin and ajoene) and lymphocytes activation (β-carotene, epigallocatechin-3-gallate, quinic acid and ginsan) properties, as well as future research direction in their use for breast cancer treatment.

  14. Reactions and Surface Transformations of a Bone-Bioactive Material in a Simulated Microgravity Environment

    NASA Technical Reports Server (NTRS)

    Radin, S.; Ducheyne, P.; Ayyaswamy, P. S.

    1999-01-01

    A comprehensive program to investigate the expeditious in vitro formation of three-dimensional bone-like tissue is currently underway at the University of Pennsylvania. The study reported here forms a part of that program. Three-dimensional bone-like tissue structures may be grown under the simulated microgravity conditions of NASA designed Rotating Wall Bioreactor Vessels (RWV's). Such tissue growth will have wide clinical applications. In addition, an understanding of the fundamental changes that occur to bone cells under simulated microgravity would yield important information that will help in preventing or minimizing astronaut bone loss, a major health issue with travel or stay in space over long periods of time. The growth of three-dimensional bone-like tissue structures in RWV's is facilitated by the use of microcarriers which provide structural support. If the microcarrier material additionally promotes bone cell growth, then it is particularly advantageous to employ such microcarriers. We have found that reactive, bone-bioactive glass (BBG) is an attractive candidate for use as microcarrier material. Specifically, it has been found that BBG containing Ca- and P- oxides upregulates osteoprogenitor cells to osteoblasts. This effect on cells is preceded by BBG reactions in solution which result in the formation of a Ca-P surface layer. This surface further transforms to a bone-like mineral (i.e., carbonated crystalline hydroxyapatite (c-HA)). At normal gravity, time-dependent, immersion-induced BBG reactions and transformations are greatly affected both by variations in the composition of the milieu in which the glass is immersed and on the immersion conditions. However, the nature of BBG reactions and phase transformations under the simulated microgravity conditions of RWV's are unknown, and must be understood in order to successfully use BBG as microcarrier material in RWV'S. In this paper, we report some of our recent findings in this regard using

  15. Bioactive Peptides

    PubMed Central

    Daliri, Eric Banan-Mwine; Oh, Deog H.; Lee, Byong H.

    2017-01-01

    The increased consumer awareness of the health promoting effects of functional foods and nutraceuticals is the driving force of the functional food and nutraceutical market. Bioactive peptides are known for their high tissue affinity, specificity and efficiency in promoting health. For this reason, the search for food-derived bioactive peptides has increased exponentially. Over the years, many potential bioactive peptides from food have been documented; yet, obstacles such as the need to establish optimal conditions for industrial scale production and the absence of well-designed clinical trials to provide robust evidence for proving health claims continue to exist. Other important factors such as the possibility of allergenicity, cytotoxicity and the stability of the peptides during gastrointestinal digestion would need to be addressed. This review discusses our current knowledge on the health effects of food-derived bioactive peptides, their processing methods and challenges in their development. PMID:28445415

  16. Bioactive Peptides.

    PubMed

    Daliri, Eric Banan-Mwine; Oh, Deog H; Lee, Byong H

    2017-04-26

    The increased consumer awareness of the health promoting effects of functional foods and nutraceuticals is the driving force of the functional food and nutraceutical market. Bioactive peptides are known for their high tissue affinity, specificity and efficiency in promoting health. For this reason, the search for food-derived bioactive peptides has increased exponentially. Over the years, many potential bioactive peptides from food have been documented; yet, obstacles such as the need to establish optimal conditions for industrial scale production and the absence of well-designed clinical trials to provide robust evidence for proving health claims continue to exist. Other important factors such as the possibility of allergenicity, cytotoxicity and the stability of the peptides during gastrointestinal digestion would need to be addressed. This review discusses our current knowledge on the health effects of food-derived bioactive peptides, their processing methods and challenges in their development.

  17. Membrane Bioreactor Technology for the Development of Functional Materials from Sea-Food Processing Wastes and Their Potential Health Benefits

    PubMed Central

    Kim, Se-Kwon; Senevirathne, Mahinda

    2011-01-01

    Sea-food processing wastes and underutilized species of fish are a potential source of functional and bioactive compounds. A large number of bioactive substances can be produced through enzyme-mediated hydrolysis. Suitable enzymes and the appropriate bioreactor system are needed to incubate the waste materials. Membrane separation is a useful technique to extract, concentrate, separate or fractionate the compounds. The use of membrane bioreactors to integrate a reaction vessel with a membrane separation unit is emerging as a beneficial method for producing bioactive materials such as peptides, chitooligosaccharides and polyunsaturated fatty acids from diverse seafood-related wastes. These bioactive compounds from membrane bioreactor technology show diverse biological activities such as antihypertensive, antimicrobial, antitumor, anticoagulant, antioxidant and radical scavenging properties. This review discusses the application of membrane bioreactor technology for the production of value-added functional materials from sea-food processing wastes and their biological activities in relation to health benefits. PMID:24957872

  18. Improvement Characteristics of Bio-active Materials Coated Fabric on Rat Muscular Mitochondria.

    PubMed

    Lee, Donghee; Kim, Young-Won; Kim, Jung-Ha; Yang, Misuk; Bae, Hyemi; Lim, Inja; Bang, Hyoweon; Go, Kyung-Chan; Yang, Gwang-Wung; Rho, Yong-Hwan; Park, Hyo-Suk; Park, Eun-Ho; Ko, Jae-Hong

    2015-05-01

    This study surveys the improvement characteristics in old-aged muscular mitochondria by bio-active materials coated fabric (BMCF). To observe the effects, the fabric (10 and 30%) was worn to old-aged rat then the oxygen consumption efficiency and copy numbers of mitochondria, and mRNA expression of apoptosis- and mitophagy-related genes were verified. By wearing the BMCF, the oxidative respiration significantly increased when using the 30% materials coated fabric. The mitochondrial DNA copy number significantly decreased and subsequently recovered in a dose-dependent manner. The respiratory control ratio to mitochondrial DNA copy number showed a dose-dependent increment. As times passed, Bax, caspase 9, PGC-1α and β-actin increased, and Bcl-2 decreased in a dose-dependent manner. However, the BMCF can be seen to have had no effect on Fas receptor. PINK1 expression did not change considerably and was inclined to decrease in control group, but the expression was down-regulated then subsequently increased with the use of the BMCF in a dose-dependent manner. Caspase 3 increased and subsequently decreased in a dose-dependent manner. These results suggest that the BMCF invigorates mitophagy and improves mitochondrial oxidative respiration in skeletal muscle, and in early stage of apoptosis induced by the BMCF is not related to extrinsic death-receptor mediated but mitochondria-mediated signaling pathway.

  19. Novel non-cytotoxic, bioactive and biodegradable hybrid materials based on polyurethanes/TiO2 for biomedical applications.

    PubMed

    González-García, Dulce M; Téllez Jurado, L; Jiménez-Gallegos, R; Rodríguez-Lorenzo, Luis M

    2017-06-01

    Titanium compounds have demonstrated great interfacial properties with biological tissues whereas a wide variety of polyurethanes have also been successfully probed in medical applications. However, studies about hybrids based on polyurethanes/TiO2 for medical applications are scarce. The aim of this work is to design novel biodegradable hybrid materials based on polyurethanes/TiO2 (80% organic-20% inorganic) and to perform a preliminary study of the potential applications in bone regeneration. The hybrids have been prepared by a sol-gel reaction using titanium isopropoxide as precursor of the inorganic component and polyurethane as the organic one. A series of polyurethanes has been prepared using different polyesters glycol succinate as soft segment, and 1,6-diisocyanatohexane (HDI) and butanediol (BD) as linear hard segment. The spectroscopy techniques used allow to confirm the formation of the required polyurethanes by the identification of bands related to carboxylic groups (COOH), and the amine groups (NH), and also the TiOH bonds and the bonds related to the interconnected network between the inorganic and the organic components from hybrids. The results from SEM/EDS show a homogeneous distribution of the inorganic component into the organic matrix. The nontoxic character of the hybrid (H400) was probed using MG-63 cell line with over 90% of cell viability. Finally, the formation of a hydroxyapatite layer in the material surface after 21days of soaking in SBF shows the bioactive character. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Identification and bioactive potential of marine microorganisms from selected Florida coastal areas.

    PubMed

    Christensen, Anna; Martin, Glenroy D A

    2017-01-26

    The ocean, with its rich untapped chemical biodiversity, continues to serve as a source of potentially new therapeutic agents. The evaluation of the diversity of cultivable microorganisms from the marine sponge Halichondria panicea and ocean sediment samples were examined and their potential as sources of antimicrobial and antiproliferative agents were investigated. The marine sponge and sediments were collected at different depths (0.9-6 meters) and locations in Florida, including Florida Keys, Port St. Joe in Pensacola, Pensacola Bay, Pensacola Beach, and Fort Pickens. Twenty-one cultivatable isolates were grouped according to their morphology and identified using 16S rRNA molecular taxonomy. The bacterial community identified consisted of members belonging to the Actinobacteria, Bacteroidetes, Proteobacteria (Alpha- and Gamma-classes) and Firmicutes phylogeny. Seven of the microbes exhibited mild to significant cytotoxic activities against five microbial indicators but no significant cytotoxic activities were observed against the pancreatic (PANC-1) nor the multidrug-resistant ovarian cancer cell lines (NCI/ADR). This work reaffirms the phyla Actinobacteria and Proteobacteria as sources of potential bioactive natural product candidates for drug discovery and development.

  1. Widespread occurrence and potential for biodegradation of bioactive contaminants in Congaree National Park, USA

    USGS Publications Warehouse

    Bradley, Paul M.; Battaglin, William A.; Clark, Jimmy M.; Henning, Frank; Hladik, Michelle; Iwanowicz, Luke; Journey, Celeste; Riley, Jeffrey W.; Romanok, Kristin

    2017-01-01

    Organic contaminants with designed molecular bioactivity, such as pesticides and pharmaceuticals, originate from human and agricultural sources, occur frequently in surface waters, and threaten the structure and function of aquatic and terrestrial ecosystems. Congaree National Park in South Carolina (USA) is a vulnerable park unit due to its location downstream of multiple urban and agricultural contaminant sources and its hydrologic setting, being composed almost entirely of floodplain and aquatic environments. Seventy-two water and sediment samples were collected from 16 sites in Congaree National Park during 2013 to 2015, and analyzed for 199 and 81 targeted organic contaminants, respectively. More than half of these water and sediment analytes were not detected or potentially had natural sources. Pharmaceutical contaminants were detected (49 total) frequently in water throughout Congaree National Park, with higher detection frequencies and concentrations at Congaree and Wateree River sites, downstream from major urban areas. Forty-seven organic wastewater indicator chemicals were detected in water, and 36 were detected in sediment, of which approximately half are distinctly anthropogenic. Endogenous sterols and hormones, which may originate from humans or wildlife, were detected in water and sediment samples throughout Congaree National Park, but synthetic hormones were detected only once, suggesting a comparatively low risk of adverse impacts. Assessment of the biodegradation potentials of 8 14C-radiolabeled model contaminants indicated poor potentials for some contaminants, particularly under anaerobic sediments conditions.

  2. [Effect of fibrin on osseointegration of bioactive glass-ceramic materials--experimental study].

    PubMed

    Urban, K; Povýsil, C; Spelda, S

    2001-01-01

    The aim of the experimental study is to find out how fibrin influences the speed of osteiontegration of bioactive glass-ceramic materials BAS-O, BAS-HA, BAS-R (LASAK Prague, Czech Republic) and how it influences the response of live tissue at the implant-bone interface in the interval of 1-8 weeks. Dense materials BAS-0 (glass-ceramics), BAS-HA (hydroxyapatite) and BAS-R (beta tricalcium phosphate) in the form of 0.6-1 mm granules were implanted in artificially created defects in tibia of an experimental animal with the addition of 0.1 ml of fibrin adhesive system Beriplast. Control implantation was performed with the addition of physiological solution. Materials BAS-HA and BAS-R were implanted in the same way in the ratio of 7:3, 8:2 and 9:1. Duration of exposure was 1-8 weeks. Radiographs of samples were taken by Mammograph and decalcified sections were coloured by toluidine blue and examined at 60 times and 120 times magnification. Surgical wounds were healed per primam. Radiographs of materials with the fibrin system showed clearly after one week defects and implants, after the third week part of the materials penetrated above the bone surface, after the fourth week there were evident signs of bone tissue formation between particles of BAS-HA, BAS-R and their mixtures. The most marked bone formation took place in the seventh and eighth weeks. With the use of glass-ceramics without fibrin the particles were after three weeks less clear, after the fourth week BAS-HA and BAS-R penetrated above the surface. A significant bone formation was obvious after the sixth and seventh weeks. There were no signs of resorption or fibrous encapsulating. Microscopic examination proved enveloping of particles of BAS-0 by fibrous tissue which was evident partially also after the eight week. With the use of fibrin the situation was analogical. In BAS-HA and BAS-R the finding in the first week was similar. With fibrin, there was after the third week a mature lamellar bone in the

  3. A review of the bioactivity and potential health benefits of peppermint tea (Mentha piperita L.).

    PubMed

    McKay, Diane L; Blumberg, Jeffrey B

    2006-08-01

    Peppermint (Mentha piperita L.) is one of the most widely consumed single ingredient herbal teas, or tisanes. Peppermint tea, brewed from the plant leaves, and the essential oil of peppermint are used in traditional medicines. Evidence-based research regarding the bioactivity of this herb is reviewed. The phenolic constituents of the leaves include rosmarinic acid and several flavonoids, primarily eriocitrin, luteolin and hesperidin. The main volatile components of the essential oil are menthol and menthone. In vitro, peppermint has significant antimicrobial and antiviral activities, strong antioxidant and antitumor actions, and some antiallergenic potential. Animal model studies demonstrate a relaxation effect on gastrointestinal (GI) tissue, analgesic and anesthetic effects in the central and peripheral nervous system, immunomodulating actions and chemopreventive potential. Human studies on the GI, respiratory tract and analgesic effects of peppermint oil and its constituents have been reported. Several clinical trials examining the effects of peppermint oil on irritable bowel syndrome (IBS) symptoms have been conducted. However, human studies of peppermint leaf are limited and clinical trials of peppermint tea are absent. Adverse reactions to peppermint tea have not been reported, although caution has been urged for peppermint oil therapy in patients with GI reflux, hiatal hernia or kidney stones.

  4. Diversity, bioactivities, and metabolic potentials of endophytic actinomycetes isolated from traditional medicinal plants in Sichuan, China.

    PubMed

    Qiu, Peng; Feng, Zhi-Xiang; Tian, Jie-Wei; Lei, Zu-Chao; Wang, Lei; Zeng, Zhi-Gang; Chu, Yi-Wen; Tian, Yong-Qiang

    2015-12-01

    The present study was designed to determine the taxonomic diversity and metabolic activity of the actinomycetes community, including 13 traditional medicinal plants collected in Sichuan province, China, using multiple approaches such as morphological and molecular identification methods, bioactivity assays, and PCR screening for genes involved in antibiotics biosynthesis. 119 endophytic actinomycetes were recovered; 80 representative strains were chosen for 16S rRNA gene partial sequence analyses, with 66 of them being affiliated to genus Streptomyces and the remaining 14 strains being rare actinomycetes. Antimicrobial tests showed that 12 (15%) of the 80 endophytic actinomycetes displayed inhibitory effects against at least one indicator pathogens, which were all assigned to the genus Streptomyces. In addition, 87.5% and 58.8% of the isolates showed anticancer and anti-diabetic activities, respectively. Meanwhile, the anticancer activities of the isolates negatively correlated with their anti-diabetic activities. Based on the results of PCR screening, five genes, PKS-I, PKS-II, NRPS, ANSA, and oxyB, were detected in 55.0%, 58.8%, 90.0%, 18.8% and 8.8% of the 80 actinomycetes, respectively. In conclusion, the PCR screening method employed in the present study was conducive for screening and selection of potential actinomycetes and predicting potential secondary metabolites, which could overcome the limitations of traditional activity screening models.

  5. Potential bioactivity of coatings formed on AZ91D magnesium alloy by plasma electrolytic anodizing.

    PubMed

    Vu, Thanh-Nam; Veys-Renaux, Delphine; Rocca, Emmanuel

    2012-10-01

    Magnesium is a potential candidate as biodegradable orthopedic implant thanks to its remarkable mechanical properties closed to those of natural bone. But its low corrosion resistance in the body fluid is a limiting factor. By using electrolytic plasma (or microarc) anodizing process, 10-20 μm protective coatings were formed on AZ91D magnesium alloys at a constant current density of 20 mA cm(-2). The effect of a small addition of CaO (1-3 g L(-1)) to a classical electrolytic bath (made of KOH 3 mol L(-1), KF 0.5 mol L(-1), and K(2)HPO(4) 1 mol L(-1)) was studied. The anodic films, investigated by X-ray diffraction and scanning electron microscope-energy dispersive spectroscopy, show a porous structure containing crystallized Mg(OH)(2), MgO, MgAl(2)O(4), as well as Ca and P elements. The 1 g L(-1) CaO-containing electrolyte leads to morphology and composition permitting optimum corrosion behavior evaluated by stationary electrochemical measurements and impedance spectroscopy. This improvement is associated with both the appearing of a "sealing" layer and the precipitation of an outermost Ca/P-containing layer (hydroxyapatite like) in simulated body fluid. The control of the corrosion behavior of coated magnesium alloys is therefore required to enhance their potential bioactivity.

  6. Bioactive and UV protective silk materials containing baicalin - The multifunctional plant extract from Scutellaria baicalensis Georgi.

    PubMed

    Zhou, Yuyang; Yang, Zhi-Yi; Tang, Ren-Cheng

    2016-10-01

    There has been a phenomenal increase in the research and development of new health and hygiene-related textile products. This work reports a novel approach to develop antibacterial, antioxidant and UV-protective silk using an adsorption technique of baicalin (a bioactive ingredient from the root of Scutellaria baicalensis Georgi). Baicalin displayed high adsorption capability at pH2.75, contributing to the sufficient functionalities on silk. The equilibrium adsorption research showed that the Langmuir isotherm was able to describe the behavior of baicalin, indicating the electrostatic interactions between the ionized carboxyl groups in baicalin and the positively charged amino groups in silk. The treated silk with 2% owf (on the weight of fiber) baicalin exhibited excellent antioxidant activity, high antibacterial activities against Escherichia coli and Staphylococcus aureus, and very good ultraviolet protection ability comparable to that of the commercial benzotriazole ultraviolet absorber. The baicalin treatment had no obvious impact on the functional groups, crystal structure and surface morphology of silk. The functionalities of the treated silk obviously declined after first laundering cycle and slowly decreased in the following washing cycles. Encouraging results demonstrate that the baicalin-functionalized silk is a promising material for protective clothing and medical textiles.

  7. [Study on injectable bioactive bone repairing material of nano-hydroxyapatite and polyamide-66 composite].

    PubMed

    Wei, Shicheng; Li, Yubao; Zheng, Qian; Wei, Jie; Zhou, Liwei; Zuo, Yi

    2003-12-01

    The aim of this study was to evaluate the injectability, histocompatibility, function and other properties of the injectable bioactive bone repairing material of nano-hydroxyapatite and polyamide-66 (n-HA/PA66) composite. The XRD pattern, the relationship between the injectability and liquid-powder ratio, setting time and liquid-powder ratio, compressive strength and liquid-powder ratio were assessed. The size of the composite was determined to be 70 nm in length and 30 to 50 nm in width, and the molecular weight of polyamides-66 was 18000. The diameter of pores of the composite was about 200 to 400 micrometer. To evaluate the histocompatibility and function, 8 male dogs were studied with the injectable n-HA/PA66 composite implanted in the artificial defected alveolus of mandible on only one side to be compared with the intact alveolus on the other side. The specimens were taken at 4, 8, 12, 16 months after the implantation and the results were evaluated. The XRD pattern of the solidificated n-HA/PA66 composite was the same as the powdered n-HA/PA66 composite. The injectable n-HA/PA66 composite had a good injectability, 25 to 30 minutes setting time and about 37 MPa compressive strength when the liquid-powder ratio was 0.50. The healing of the gingiva was well at the implanted areas in all animals. The height of the repaired alveolar bone was obvious higher than that of the blank control. The earlier sign of ossification was histologically observed at 16 weeks after implantation. The injectable n-HA/PA66 composite has good biocompatibility and osteoconductive property. As an injectable material, with good maneuverability, it is useful for repairing irregular bone defects, especially in oral and maxillofacial surgery.

  8. Coatings of titanium substrates with xCaO · (1 - x)SiO2 sol-gel materials: characterization, bioactivity and biocompatibility evaluation.

    PubMed

    Catauro, M; Papale, F; Bollino, F

    2016-01-01

    The objective of this study has been to develop low temperature sol-gel coatings to modify the surface of commercially pure titanium grade 4 (a material generally used in dental application) and to evaluate their bioactivity and biocompatibility on the substrate. Glasses of composition expressed by the following general formula xCaO · (1 - x)SiO2 (0.0materials, still in the sol phase, have been used to coat titanium substrates by means of the dip-coating technique. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) allowed the materials to be characterized and a microstructural analysis of the coatings obtained was performed using scanning electron microscopy (SEM). The potential applications of the coatings in the biomedical field were evaluated by bioactivity and biocompatibility tests. The coated titanium was immersed in simulated body fluid (SBF) for 21 days and the hydroxyapatite deposition on its surface was subsequently evaluated via SEM-EDXS analysis, as an index of bone-bonding capability. To investigate cell-material interactions, mouse embryonic fibroblast cells (3T3) were seeded onto the specimens and the cell viability was evaluated by a WST-8 assay. Copyright © 2015. Published by Elsevier B.V.

  9. Protective effects of bioactive phytochemicals from Mentha piperita with multiple health potentials.

    PubMed

    Sharafi, Seyedeh Maryam; Rasooli, Iraj; Owlia, Parviz; Taghizadeh, Massoud; Astaneh, Shakiba Darvish Alipoor

    2010-07-01

    Mentha piperita essential oil was bactericidal in order of E. coli> S. aureus > Pseudomonas aeruginosa > S. faecalis > Klebsiella pneumoniae. The oil with total phenolics of 89.43 ± 0.58 µg GAE/mg had 63.82 ± 0.05% DPPH inhibition activity with an IC (50) = 3.9 µg/ml. Lipid peroxidation inhibition was comparable to BHT and BHA. A 127% hike was noted in serum ferric-reducing antioxidant power. There was 38.3% decrease in WBCs count, while platelet count showed increased levels of 214.12%. Significant decrease in uric acid level and cholesterol/HDL and LDL/HDL ratios were recorded. The volatile oil displayed high cytotoxic action toward the human tumor cell line. The results of this study deserve attention with regard to antioxidative and possible anti-neoplastic chemotherapy that form a basis for future research. The essential oil of mint may be exploited as a natural source of bioactive phytopchemicals bearing antimicrobial and antioxidant potentials that could be supplemented for both nutritional purposes and preservation of foods.

  10. Bioactive vegetable proteins and peptides in lipid-lowering; nutraceutical potential.

    PubMed

    Ruiz Ruiz, Jorge Carlos; Betancur Ancona, David Abram; Segura Campos, Maira Rubi

    2014-04-01

    As the last century saw a decline in the burden of nutritional deficiency and infectious disease, the global burden of chronic disease, cardiovascular disease (CVD) in particular, is increasing. CVD is the leading cause of death in the developed countries. Significant research efforts on the prevention and treatment of this disease have identified elevated plasma cholesterol as a primary risk factor for CVD. Although CVD progresses with hypercholesterolemia, it seems possibility to delay and prevent its development through improvement of diet. Recent findings demonstrate that protein concentrates, protein hydrolysates, and peptides derived from vegetables may promote a significant decrease in blood cholesterol concentration. This reduction in cholesterol and lipid levels by protein, protein hydrolysates, and peptides can be the result of dietary changes, reduced cholesterol biosynthesis, changes in bile acid synthesis, and reduced absorption of lipid cholesterol and bile acid. Combination drug/diet therapies may reduce the number of drug prescriptions, the progressive rise in "optimal" drug dosage and costs associated with pharmaceutical management of disease. These bioactive vegetable proteins, hydrolysates and peptides may be used in formulation of functional foods, nutraceuticals, and natural drugs because of their health benefit effects suggesting their use as an alternative in treatment of various dyslipidemias, and a potential agent for reducing cardiovascular diseases risk factors.

  11. Looking Beyond the Terrestrial: The Potential of Seaweed Derived Bioactives to Treat Non-Communicable Diseases.

    PubMed

    Collins, Kenneth G; Fitzgerald, Gerald F; Stanton, Catherine; Ross, R Paul

    2016-03-18

    Seaweeds are a large and diverse group of marine organisms that are commonly found in the maritime regions of the world. They are an excellent source of biologically active secondary metabolites and have been shown to exhibit a wide range of therapeutic properties, including anti-cancer, anti-oxidant, anti-inflammatory and anti-diabetic activities. Several Asian cultures have a strong tradition of using different varieties of seaweed extensively in cooking as well as in herbal medicines preparations. As such, seaweeds have been used to treat a wide variety of health conditions such as cancer, digestive problems, and renal disorders. Today, increasing numbers of people are adopting a "westernised lifestyle" characterised by low levels of physical exercise and excessive calorific and saturated fat intake. This has led to an increase in numbers of chronic Non-communicable diseases (NCDs) such as cancer, cardiovascular disease, and diabetes mellitus, being reported. Recently, NCDs have replaced communicable infectious diseases as the number one cause of human mortality. Current medical treatments for NCDs rely mainly on drugs that have been obtained from the terrestrial regions of the world, with the oceans and seas remaining largely an untapped reservoir for exploration. This review focuses on the potential of using seaweed derived bioactives including polysaccharides, antioxidants and fatty acids, amongst others, to treat chronic NCDs such as cancer, cardiovascular disease and diabetes mellitus.

  12. Looking Beyond the Terrestrial: The Potential of Seaweed Derived Bioactives to Treat Non-Communicable Diseases

    PubMed Central

    Collins, Kenneth G.; Fitzgerald, Gerald F.; Stanton, Catherine; Ross, R. Paul

    2016-01-01

    Seaweeds are a large and diverse group of marine organisms that are commonly found in the maritime regions of the world. They are an excellent source of biologically active secondary metabolites and have been shown to exhibit a wide range of therapeutic properties, including anti-cancer, anti-oxidant, anti-inflammatory and anti-diabetic activities. Several Asian cultures have a strong tradition of using different varieties of seaweed extensively in cooking as well as in herbal medicines preparations. As such, seaweeds have been used to treat a wide variety of health conditions such as cancer, digestive problems, and renal disorders. Today, increasing numbers of people are adopting a “westernised lifestyle” characterised by low levels of physical exercise and excessive calorific and saturated fat intake. This has led to an increase in numbers of chronic Non-communicable diseases (NCDs) such as cancer, cardiovascular disease, and diabetes mellitus, being reported. Recently, NCDs have replaced communicable infectious diseases as the number one cause of human mortality. Current medical treatments for NCDs rely mainly on drugs that have been obtained from the terrestrial regions of the world, with the oceans and seas remaining largely an untapped reservoir for exploration. This review focuses on the potential of using seaweed derived bioactives including polysaccharides, antioxidants and fatty acids, amongst others, to treat chronic NCDs such as cancer, cardiovascular disease and diabetes mellitus. PMID:26999166

  13. Protective effects of bioactive phytochemicals from Mentha piperita with multiple health potentials

    PubMed Central

    Sharafi, Seyedeh Maryam; Rasooli, Iraj; Owlia, Parviz; Taghizadeh, Massoud; Astaneh, Shakiba Darvish Alipoor

    2010-01-01

    Mentha piperita essential oil was bactericidal in order of E. coli> S. aureus > Pseudomonas aeruginosa > S. faecalis > Klebsiella pneumoniae. The oil with total phenolics of 89.43 ± 0.58 µg GAE/mg had 63.82 ± 0.05% DPPH inhibition activity with an IC 50 = 3.9 µg/ml. Lipid peroxidation inhibition was comparable to BHT and BHA. A 127% hike was noted in serum ferric-reducing antioxidant power. There was 38.3% decrease in WBCs count, while platelet count showed increased levels of 214.12%. Significant decrease in uric acid level and cholesterol/HDL and LDL/HDL ratios were recorded. The volatile oil displayed high cytotoxic action toward the human tumor cell line. The results of this study deserve attention with regard to antioxidative and possible anti-neoplastic chemotherapy that form a basis for future research. The essential oil of mint may be exploited as a natural source of bioactive phytopchemicals bearing antimicrobial and antioxidant potentials that could be supplemented for both nutritional purposes and preservation of foods. PMID:20931070

  14. Lipids and Fatty Acids of Nudibranch Mollusks: Potential Sources of Bioactive Compounds

    PubMed Central

    Zhukova, Natalia V.

    2014-01-01

    The molecular diversity of chemical compounds found in marine animals offers a good chance for the discovery of novel bioactive compounds of unique structures and diverse biological activities. Nudibranch mollusks, which are not protected by a shell and produce chemicals for various ecological uses, including defense against predators, have attracted great interest for their lipid composition. Lipid analysis of eight nudibranch species revealed dominant phospholipids, sterols and monoalkyldiacylglycerols. Among polar lipids, 1-alkenyl-2-acyl glycerophospholipids (plasmalogens) and ceramide-aminoethyl phosphonates were found in the mollusks. The fatty acid compositions of the nudibranchs differed greatly from those of other marine gastropods and exhibited a wide diversity: very long chain fatty acids known as demospongic acids, a series of non-methylene-interrupted fatty acids, including unusual 21:2∆7,13, and an abundance of various odd and branched fatty acids typical of bacteria. Symbiotic bacteria revealed in some species of nudibranchs participate presumably in the production of some compounds serving as a chemical defense for the mollusks. The unique fatty acid composition of the nudibranchs is determined by food supply, inherent biosynthetic activities and intracellular symbiotic microorganisms. The potential of nudibranchs as a source of biologically active lipids and fatty acids is also discussed. PMID:25196731

  15. Cymbopogon citratus industrial waste as a potential source of bioactive compounds.

    PubMed

    Tavares, Filipa; Costa, Gustavo; Francisco, Vera; Liberal, Joana; Figueirinha, Artur; Lopes, Maria Celeste; Cruz, Maria Teresa; Batista, Maria Teresa

    2015-10-01

    Cymbopogon citratus (Cc), commonly known as lemongrass, is a very important crop worldwide, being grown in tropical countries. It is widely used in the food, pharmaceutical, cosmetic and perfumery industries for its essential oil. Cc aqueous extracts are also used in traditional medicine. They contain high levels of polyphenols, which are known for their antioxidant and anti-inflammatory properties. Hydrodistillation of lemongrass essential oil produces an aqueous waste (CcHD) which is discarded. Therefore a comparative study between CcHD and Cc infusion (CcI) was performed to characterize its phytochemical profile and to research its antioxidant and anti-inflammatory potential. HPLC-PDA/ESI-MS(n) analysis showed that CcI and CcHD have similar phenolic profiles, with CcHD presenting a higher amount of polyphenols. Additionally, both CcI and CcHD showed antioxidant activity against DPPH (EC50 of 41.72 ± 0.05 and 42.29 ± 0.05 µg mL(-1) respectively) and strong anti-inflammatory properties, by reducing NO production and iNOS expression in macrophages and through their NO-scavenging activity, in a dose-dependent manner. Furthermore, no cytotoxicity was observed. The data of this study encourage considering the aqueous solution from Cc leaf hydrodistillation as a source of bioactive compounds, which may add great industrial value to this crop. © 2014 Society of Chemical Industry.

  16. Invited review: Milk phospholipid vesicles, their colloidal properties, and potential as delivery vehicles for bioactive molecules.

    PubMed

    Arranz, E; Corredig, M

    2017-06-01

    The milk fat globule membrane (MFGM) is a unique colloidal assembly of phospholipids and proteins, with numerous potential applications as functional ingredient. The phospholipid components of the MFGM are gaining interest as they are a useful matrix for use as a constituent of delivery systems such as liposomes. Liposomes formulated with milk phospholipids are becoming an alternative to other sources of phospholipids such as soybean or egg yolk. However, incorporation of phospholipids fractionated from the milk fat globule membrane in dairy products requires an in-depth understanding of the functional properties of phospholipids. In particular, it is critical to understand which factors play a role in their stability and bioefficacy as delivery systems. Moreover, chemical and physical modifications of phospholipid liposomes occurring during digestion and the fate of the encapsulated compounds are very important to understand. This review discusses recent findings on the structure and functionality of MFGM, the bioactivity of the phospholipids fraction, their utilization as delivery systems, and their stability through gastrointestinal transit. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  17. Structural characterization and anti-cancerous potential of gallium bioactive glass/hydrogel composites.

    PubMed

    Keenan, T J; Placek, L M; Coughlan, A; Bowers, G M; Hall, M M; Wren, A W

    2016-11-20

    A bioactive glass series (0.42SiO2-0.10Na2O-0.08CaO-(0.40-X)ZnO-(X)Ga2O3) was incorporated into carboxymethyl cellulose (CMC)/dextran (Dex) hydrogels in three different amounts (0.05, 0.10, and 0.25m(2)), and the resulting composites were characterized using transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and (13)C Cross Polarization Magic Angle Spinning Nuclear Magnetic Resonance (CP MAS-NMR). Composite extracts were also evaluated in vitro against MG-63 osteosarcoma cells. TEM confirmed glass distribution throughout the composites, although some particle agglomeration was observed. DSC revealed that glass composition and content did have small effects on both Tg and Tm. MAS-NMR revealed that both CMC and Dex were successfully functionalized, that cross-linking occurred, and that glass addition did slightly alter bonding environments. Cell viability analysis suggested that extracts of the glass and composites with the largest Ga-content significantly decreased MG-63 osteosarcoma viability after 30days. This study successfully characterized this composite series, and demonstrated their potential for anti-cancerous applications.

  18. Bioactivity of Nonedible Parts of Punica granatum L.: A Potential Source of Functional Ingredients

    PubMed Central

    Somanah, Jhoti; Ramsaha, Srishti; Bahorun, Theeshan; Neergheen-Bhujun, Vidushi S.

    2013-01-01

    Punica granatum L. has a long standing culinary and medicinal traditional use in Mauritius. This prompted a comparative study to determine the bioefficacy of the flower, peel, leaf, stem, and seed extracts of the Mauritian P. granatum. The flower and peel extracts resulting from organic solvent extraction exhibited strong antioxidant activities which correlated with the high levels of total phenolics, flavonoids, and proanthocyanidins. The peel extract had the most potent scavenging capacity reflected by high Trolox equivalent antioxidant capacity value (5206.01 ± 578.48 μmol/g air dry weight), very low IC50 values for hypochlorous acid (0.004 ± 0.001 mg air dry weight/mL), and hydroxyl radicals scavenging (0.111 ± 0.001 mg air dry weight/mL). Peel extracts also significantly inhibited S. mutans (P < 0.001), S. mitis (P < 0.001), and L. acidophilus (P < 0.05) growth compared to ciprofloxacin. The flower extract exhibited high ferric reducing, nitric oxide scavenging, and iron (II) ions chelation and significantly inhibited microsomal lipid peroxidation. Furthermore, it showed a dose-dependent inhibition of xanthine oxidase with an IC50 value of 0.058 ± 0.011 mg air dry weight/mL. This study showed that nonedible parts of cultivated pomegranates, that are generally discarded, are bioactive in multiassay systems thereby suggesting their potential use as natural prophylactics and in food applications. PMID:26904607

  19. Small peptides, big world: biotechnological potential in neglected bioactive peptides from arthropod venoms.

    PubMed

    Pimenta, Adriano M C; De Lima, Maria Elena

    2005-11-01

    Until recently, a toxinologist's tasks involved the search for highly toxic or lethal toxins in animal venoms that could explain the harmful effects in clinically observed symptoms. Most of these toxins were put on evidence using a function to structure approach, in which a biological phenomena observation usually guided the isolation and characterization of the causative molecule. Paving this way, many toxins were promptly purified because of their readily observed effect. Nevertheless, small molecules with micro-effects that are not easily visualized can be relatively neglected or poorly studied. This situation has changed now with the advent of the sensitivity, resolution and accuracy of techniques such as mass spectrometry and proteomic approaches used in toxinology. Taking advantage of these methodologies, small peptides with 'newly exploited' biological activities such as vasoactive, hormone-like, antimicrobial and others have been recently given much more attention, enlarging the known repertoire of bioactive molecules found in animal venoms. This article aims to review current knowledge on small biologically active peptides (<3 kDa) found in arthropod venoms and discuss their potentialities as new drug candidates or therapeutic lead compounds. Copyright 2005 European Peptide Society and John Wiley & Sons, Ltd.

  20. A novel synthetic material for spinal fusion: a prospective clinical trial of porous bioactive titanium metal for lumbar interbody fusion.

    PubMed

    Fujibayashi, Shunsuke; Takemoto, Mitsuru; Neo, Masashi; Matsushita, Tomiharu; Kokubo, Tadashi; Doi, Kenji; Ito, Tatsuya; Shimizu, Akira; Nakamura, Takashi

    2011-09-01

    The objective of this study was to establish the efficacy and safety of porous bioactive titanium metal for use in a spinal fusion device, based on a prospective human clinical trial. A high-strength spinal interbody fusion device was manufactured from porous titanium metal. A bioactive surface was produced by simple chemical and thermal treatment. Five patients with unstable lumbar spine disease were treated surgically using this device in a clinical trial approved by our Ethics Review Committee and the University Hospital Medical Information Network. Clinical and radiological results were reported at the minimum follow-up period of 1 year. The optimal mechanical strength and interconnected structure of the porous titanium metal were adjusted for the device. The whole surface of porous titanium metal was treated uniformly and its bioactive ability was confirmed before clinical use. Successful bony union was achieved in all cases within 6 months without the need for autologous iliac crest bone grafting. Two specific findings including an anchoring effect and gap filling were evident radiologically. All clinical parameters improved significantly after the operation and no adverse effects were encountered during the follow-up period. Although a larger and longer-term follow-up clinical study is mandatory to reach any firm conclusions, the study results show that this porous bioactive titanium metal is promising material for a spinal fusion device.

  1. Widespread occurrence and potential for biodegradation of bioactive contaminants in Congaree National Park, USA.

    PubMed

    Bradley, Paul M; Battaglin, William A; Clark, Jimmy M; Henning, Frank P; Hladik, Michelle L; Iwanowicz, Luke R; Journey, Celeste A; Riley, Jeffrey W; Romanok, Kristin M

    2017-06-21

    Organic contaminants with designed molecular bioactivity, such as pesticides and pharmaceuticals, originate from human and agricultural sources, occur frequently in surface waters, and threaten the structure and function of aquatic and terrestrial ecosystems. Congaree National Park in South Carolina (USA) is a vulnerable park unit due to its location downstream of multiple urban and agricultural contaminant sources and its hydrologic setting, being composed almost entirely of floodplain and aquatic environments. Seventy-two water and sediment samples were collected from 16 sites in Congaree National Park during 2013 to 2015, and analyzed for 199 and 81 targeted organic contaminants, respectively. More than half of these water and sediment analytes were not detected or potentially had natural sources. Pharmaceutical contaminants were detected (49 total) frequently in water throughout Congaree National Park, with higher detection frequencies and concentrations at Congaree and Wateree River sites, downstream from major urban areas. Forty-seven organic wastewater indicator chemicals were detected in water, and 36 were detected in sediment, of which approximately half are distinctly anthropogenic. Endogenous sterols and hormones, which may originate from humans or wildlife, were detected in water and sediment samples throughout Congaree National Park, but synthetic hormones were detected only once, suggesting a comparatively low risk of adverse impacts. Assessment of the biodegradation potentials of 8 (14) C-radiolabeled model contaminants indicated poor potentials for some contaminants, particularly under anaerobic sediments conditions. Environ Toxicol Chem 2017;9999:1-12. Published 2017 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. Published 2017 Wiley Periodicals Inc., on behalf of SETAC.

  2. Bioactive materials improve some physical properties of a MTA-like cement.

    PubMed

    Flores-Ledesma, A; Barceló Santana, F; Bucio, L; Arenas-Alatorre, J A; Faraji, M; Wintergerst, A M

    2017-02-01

    One of the main disadvantages of MTA is its long setting time which could result in higher solubility and microleakage, producing a failed treatment. Studies have shown that the addition of bioactive glass may decrease the setting time. The aim of this study is to evaluate the compressive strength, setting time, solubility and radiopacity of a MTAlike experimental cement to which different percentage of wollastonite and bioactive glass are added. White MTA Angelus® was used as control; an experimental MTA-like cement (ExpC) was prepared using white Portland cement with 20wt% of Bi2O3; three wollastonite cement composites were prepared adding 10, 20 and 30wt% of wollastonite to ExpC, and three more adding the same proportions of bioactive glass. Compressive strength was tested according to ADA 30; radiopacity, setting time and solubility were tested according to ISO 6876. SEM observations of the surface were made after the solubility test. Compressive strength, setting time, solubility and radiopacity were reduced as the wollastonite increased; solubility increased with the addition of bioactive glass. The surfaces of MTA Angelus® and ExpC were smoother than Wollastonite and Bioactive glass groups. Addition of wollastonite and bioactive glass improved the physical properties of a MTA-like experimental cement, reducing the setting time with good solubility percentages, which would be an advantage in its clinical use. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Leveraging "raw materials" as building blocks and bioactive signals in regenerative medicine.

    PubMed

    Renth, Amanda N; Detamore, Michael S

    2012-10-01

    Components found within the extracellular matrix (ECM) have emerged as an essential subset of biomaterials for tissue engineering scaffolds. Collagen, glycosaminoglycans, bioceramics, and ECM-based matrices are the main categories of "raw materials" used in a wide variety of tissue engineering strategies. The advantages of raw materials include their inherent ability to create a microenvironment that contains physical, chemical, and mechanical cues similar to native tissue, which prove unmatched by synthetic biomaterials alone. Moreover, these raw materials provide a head start in the regeneration of tissues by providing building blocks to be bioresorbed and incorporated into the tissue as opposed to being biodegraded into waste products and removed. This article reviews the strategies and applications of employing raw materials as components of tissue engineering constructs. Utilizing raw materials holds the potential to provide both a scaffold and a signal, perhaps even without the addition of exogenous growth factors or cytokines. Raw materials contain endogenous proteins that may also help to improve the translational success of tissue engineering solutions to progress from laboratory bench to clinical therapies. Traditionally, the tissue engineering triad has included cells, signals, and materials. Whether raw materials represent their own new paradigm or are categorized as a bridge between signals and materials, it is clear that they have emerged as a leading strategy in regenerative medicine. The common use of raw materials in commercial products as well as their growing presence in the research community speak to their potential. However, there has heretofore not been a coordinated or organized effort to classify these approaches, and as such we recommend that the use of raw materials be introduced into the collective consciousness of our field as a recognized classification of regenerative medicine strategies.

  4. Effect of anodization and alkali-heat treatment on the bioactivity of titanium implant material (an in vitro study)

    PubMed Central

    Abdelrahim, Ramy A.; Badr, Nadia A.; Baroudi, Kusai

    2016-01-01

    Objective: This study was aimed to assess the effect of anodized and alkali-heat surface treatment on the bioactivity of titanium alloy (Ti-6Al-4V) after immersion in Hank's solution for 7 days. Materials and Methods: Fifteen titanium alloy samples were used in this study. The samples were divided into three groups (five for each), five samples were anodized in 1M H3PO4 at constant voltage value of 20 v and another five samples were alkali-treated in 5 M NaOH solution for 25 min at temperature 60°C followed by heat treatment at 600°C for 1 h. All samples were then immersed in Hank's solution for 7 days to assess the effect of surface modifications on the bioactivity of titanium alloy. The different treated surfaces and control one were characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier transformation infra-red spectroscopy. Statistical analysis was performed with PASW Statistics 18.0® (Predictive Analytics Software). Results: Anodization of Ti-alloy samples (Group B) led to the formation of bioactive titanium oxide anatase phase and PO43− group on the surface. The alkali-heat treatment of titanium alloy samples (Group C) leads to the formation of bioactive titania hydrogel and supplied sodium ions. The reaction between the Ti sample and NaOH alkaline solution resulted in the formation of a layer of amorphous sodium titania on the Ti surface, and this layer can induce apatite deposition. Conclusions: The surface roughness and surface chemistry had an excellent ability to induce bioactivity of titanium alloy. The anodization in H3PO4 produced anatase titanium oxide on the surface with phosphate originated from electrolytes changed the surface topography and allowed formation of calcium-phosphate. PMID:27382532

  5. Genus Kadsura, a good source with considerable characteristic chemical constituents and potential bioactivities.

    PubMed

    Liu, Jiushi; Qi, Yaodong; Lai, Hongwu; Zhang, Jin; Jia, Xiaoguang; Liu, Haitao; Zhang, Bengang; Xiao, Peigen

    2014-01-01

    In China, the plants of genus Kadsura had been used as the folk medicines for a long time and showed good effect of activating blood and dissolving stasis, promoting qi circulation to relieve pain, dispelling wind and eliminating dampness. The bioactivities of genus Kadsura were attributed to the existence of its characteristic chemical constituents. This review systematically summarized the traditional efficacy and medicinal application of genus Kadsura in China, chemical constituents and bioactivities of the plants of genus Kadsura. And, lignans and triterpenoids were the main bioactive constituents, which exhibited good anti-HIV, anti-tumor, anti-hepatitis, anti-oxidant, anti-platelet aggregation activities and neuroprotective effect etc. Moreover, some structure-activity relationships mining would greatly enrich the opportunity of finding new and promising lead compounds and promote the reasonable development and utilization of the plants of genus Kadsura. Copyright © 2014 Elsevier GmbH. All rights reserved.

  6. Bioactive Proteins in Human Milk-Potential Benefits for Preterm Infants.

    PubMed

    Lönnerdal, Bo

    2017-03-01

    Human milk contains many bioactive proteins that are likely to be involved in the better outcomes of breast-fed infants compared with those fed infant formula. Bovine milk proteins or protein fractions may be able to provide some of these benefits and may, therefore, be used for preterm infants. Recombinant human milk proteins are likely to exert bioactivities similar to those of the native human milk proteins, but considerable research is needed before they can be used in routine care of preterm infants.

  7. Present and future of glass-ionomers and calcium-silicate cements as bioactive materials in dentistry: biophotonics-based interfacial analyses in health and disease.

    PubMed

    Watson, Timothy F; Atmeh, Amre R; Sajini, Shara; Cook, Richard J; Festy, Frederic

    2014-01-01

    Since their introduction, calcium silicate cements have primarily found use as endodontic sealers, due to long setting times. While similar in chemistry, recent variations such as constituent proportions, purities and manufacturing processes mandate a critical understanding of service behavior differences of the new coronal restorative material variants. Of particular relevance to minimally invasive philosophies is the potential for ion supply, from initial hydration to mature set in dental cements. They may be capable of supporting repair and remineralization of dentin left after decay and cavity preparation, following the concepts of ion exchange from glass ionomers. This paper reviews the underlying chemistry and interactions of glass ionomer and calcium silicate cements, with dental tissues, concentrating on dentin-restoration interface reactions. We additionally demonstrate a new optical technique, based around high resolution deep tissue, two-photon fluorescence and lifetime imaging, which allows monitoring of undisturbed cement-dentin interface samples behavior over time. The local bioactivity of the calcium-silicate based materials has been shown to produce mineralization within the subjacent dentin substrate, extending deep within the tissues. This suggests that the local ion-rich alkaline environment may be more favorable to mineral repair and re-construction, compared with the acidic environs of comparable glass ionomer based materials. The advantages of this potential re-mineralization phenomenon for minimally invasive management of carious dentin are self-evident. There is a clear need to improve the bioactivity of restorative dental materials and these calcium silicate cement systems offer exciting possibilities in realizing this goal. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  8. Renal net acid excretion and plasma leptin are associated with potentially bioactive free glucocorticoids in healthy lean women.

    PubMed

    Remer, Thomas; Dimitriou, Triantafillia; Maser-Gluth, Christiane

    2008-02-01

    Primarily experimental evidence suggests that endogenous glucocorticoids may be suppressed by adipocyte-derived leptin and elevated by dietary acidity. Therefore, we examined whether these factors may also be relevant in healthy adults on unrestricted diets. For this we used a new methodological approach in which potentially bioactive free glucocorticoids were determined as the sum of urinary free cortisol and urinary free cortisone and that also takes into account total adrenal glucocorticoid secretion assessed by the sum of the 3 major urinary glucocorticoid metabolites tetrahydrocortisone, tetrahydrocortisol, and 5alpha-tetrahydrocortisol. Body composition, plasma cortisol, plasma leptin, and 24-h urinary excretion rates of net acid and glucocorticoid metabolites were examined cross-sectionally in 30 healthy adults (15 women; 22-44 y old; BMI 20-25 kg/m2). Plasma leptin, percentage body fat, and body surface area-corrected adrenal glucocorticoid secretion showed the usual sex dimorphism (male vs. female, P < 0.05 in each case: 2.8 +/- 1.6 microg/L vs. 7.6 +/- 4.9 microg/L, 16.8 +/- 4.2% vs. 26.9 +/- 4.9%, and 5.1 +/- 1.6 mg x m(-2) x d(-1) vs. 4.0 +/- 1.3 mg x m(-2) x d(-1), respectively), whereas net acid excretion, plasma cortisol, and potentially bioactive free glucocorticoids did not differ between the sexes. Potentially bioactive free glucocorticoids correlated positively with body fat and leptin in men (P < 0.05) but not in women. After adjustment for total adrenal glucocorticoid secretion, net acid excretion was a positive and leptin a negative predictor (P < 0.05) of potentially bioactive free glucocorticoids in women only (total explained variability R2 = 0.71). Our findings indicate that, at least in women, variability of potentially bioactive free glucocorticoids is not only explained by adrenal glucocorticoid secretion but is also metabolically affected by circulating leptin and diet-dependent net acid excretion.

  9. Bioactivity studies and adhesion of human osteoblast (hFOB) on silicon-biphasic calcium phosphate material.

    PubMed

    Ibrahim, S; Sabudin, S; Sahid, S; Marzuke, M A; Hussin, Z H; Kader Bashah, N S; Jamuna-Thevi, K

    2016-01-01

    Surface reactivity of bioactive ceramics contributes in accelerating bone healing by anchoring osteoblast cells and the connection of the surrounding bone tissues. The presence of silicon (Si) in many biocompatible and bioactive materials has been shown to improve osteoblast cell adhesion, proliferation and bone regeneration due to its role in the mineralisation process around implants. In this study, the effects of Si-biphasic calcium phosphate (Si-BCP) on bioactivity and adhesion of human osteoblast (hFOB) as an in vitro model have been investigated. Si-BCP was synthesised using calcium hydroxide (Ca(OH)2) and phosphoric acid (H3PO4) via wet synthesis technique at Ca/P ratio 1.60 of material precursors. SiO2 at 3 wt% based on total precursors was added into apatite slurry before proceeding with the spray drying process. Apatite powder derived from the spray drying process was pressed into discs with Ø 10 mm. Finally, the discs were sintered at atmospheric condition to obtain biphasic hydroxyapatite (HA) and tricalcium phosphate (TCP) peaks simultaneously and examined by XRD, AFM and SEM for its bioactivity evaluation. In vitro cell viability of L929 fibroblast and adhesion of hFOB cell were investigated via AlamarBlue® (AB) assay and SEM respectively. All results were compared with BCP without Si substitution. Results showed that the presence of Si affected the material's surface and morphology, cell proliferation and cell adhesion. AFM and SEM of Si-BCP revealed a rougher surface compared to BCP. Bioactivity in simulated body fluid (SBF) was characterised by pH, weight gain and apatite mineralisation on the sample surface whereby the changes in surface morphology were evaluated using SEM. Immersion in SBF up to 21 days indicated significant changes in pH, weight gain and apatite formation. Cell viability has demonstrated no cytotoxic effect and denoted that Si-BCP promoted good initial cell adhesion and proliferation. These results suggest that Si

  10. Bioactive glass-ionomer cement with potential therapeutic function to dentin capping mineralization.

    PubMed

    Xie, Dong; Zhao, Jun; Weng, Yiming; Park, Jong-Gu; Jiang, Hui; Platt, Jeffrey A

    2008-10-01

    We have developed a novel bioactive resin-modified glass-ionomer cement system with therapeutic function to dentin capping mineralization. In the system, the newly synthesized star-shape poly(acrylic acid) was formulated with water, Fuji II LC filler, and bioactive glass S53P4 to form resin-modified glass-ionomer cement. Compressive strength (CS) was used as a screening tool for evaluation. The commercial glass-ionomer cement Fuji II LC was used as a control. All the specimens were conditioned in simulated body fluid (SBF) at 37 degrees C prior to testing. The effect of aging in SBF on CS and microhardness of the cements was investigated. Scanning electron microscopy was used to examine the in vitro dentin surface changes caused by the incorporation of bioactive glass. The results show that the system not only provided strengths comparable to original commercial Fuji II LC cement but also allowed the cement to help mineralize the dentin in the presence of SBF. It appears that this bioactive glass-ionomer cement system has direct therapeutic impact on dental restorations that require root surface fillings.

  11. Functional food productions: release the potential of bioactive compounds through food processing

    USDA-ARS?s Scientific Manuscript database

    Epidemiological studies of bioactive compounds from plant-based foods have consistently pointed to undisputed benefits of consumption of plant-based foods on human health particularly regarding cardiovascular diseases and cancers. However, in order to attain the dosage required from these studies, p...

  12. Concrete: Potential material for Space Station

    NASA Technical Reports Server (NTRS)

    Lin, T. D.

    1992-01-01

    To build a permanent orbiting space station in the next decade is NASA's most challenging and exciting undertaking. The space station will serve as a center for a vast number of scientific products. As a potential material for the space station, reinforced concrete was studied, which has many material and structural merits for the proposed space station. Its cost-effectiveness depends on the availability of lunar materials. With such materials, only 1 percent or less of the mass of a concrete space structure would have to be transported from earth.

  13. Present and future of glass-ionomers and calcium-silicate cements as bioactive materials in dentistry: Biophotonics-based interfacial analyses in health and disease

    PubMed Central

    Watson, Timothy F.; Atmeh, Amre R.; Sajini, Shara; Cook, Richard J.; Festy, Frederic

    2014-01-01

    Objective Since their introduction, calcium silicate cements have primarily found use as endodontic sealers, due to long setting times. While similar in chemistry, recent variations such as constituent proportions, purities and manufacturing processes mandate a critical understanding of service behavior differences of the new coronal restorative material variants. Of particular relevance to minimally invasive philosophies is the potential for ion supply, from initial hydration to mature set in dental cements. They may be capable of supporting repair and remineralization of dentin left after decay and cavity preparation, following the concepts of ion exchange from glass ionomers. Methods This paper reviews the underlying chemistry and interactions of glass ionomer and calcium silicate cements, with dental tissues, concentrating on dentin–restoration interface reactions. We additionally demonstrate a new optical technique, based around high resolution deep tissue, two-photon fluorescence and lifetime imaging, which allows monitoring of undisturbed cement–dentin interface samples behavior over time. Results The local bioactivity of the calcium-silicate based materials has been shown to produce mineralization within the subjacent dentin substrate, extending deep within the tissues. This suggests that the local ion-rich alkaline environment may be more favorable to mineral repair and re-construction, compared with the acidic environs of comparable glass ionomer based materials. Significance The advantages of this potential re-mineralization phenomenon for minimally invasive management of carious dentin are self-evident. There is a clear need to improve the bioactivity of restorative dental materials and these calcium silicate cement systems offer exciting possibilities in realizing this goal. PMID:24113131

  14. Bioactivity studies and adhesion of human osteoblast (hFOB) on silicon-biphasic calcium phosphate material

    PubMed Central

    Ibrahim, S.; Sabudin, S.; Sahid, S.; Marzuke, M.A.; Hussin, Z.H.; Kader Bashah, N.S.; Jamuna-Thevi, K.

    2015-01-01

    Surface reactivity of bioactive ceramics contributes in accelerating bone healing by anchoring osteoblast cells and the connection of the surrounding bone tissues. The presence of silicon (Si) in many biocompatible and bioactive materials has been shown to improve osteoblast cell adhesion, proliferation and bone regeneration due to its role in the mineralisation process around implants. In this study, the effects of Si-biphasic calcium phosphate (Si-BCP) on bioactivity and adhesion of human osteoblast (hFOB) as an in vitro model have been investigated. Si-BCP was synthesised using calcium hydroxide (Ca(OH)2) and phosphoric acid (H3PO4) via wet synthesis technique at Ca/P ratio 1.60 of material precursors. SiO2 at 3 wt% based on total precursors was added into apatite slurry before proceeding with the spray drying process. Apatite powder derived from the spray drying process was pressed into discs with Ø 10 mm. Finally, the discs were sintered at atmospheric condition to obtain biphasic hydroxyapatite (HA) and tricalcium phosphate (TCP) peaks simultaneously and examined by XRD, AFM and SEM for its bioactivity evaluation. In vitro cell viability of L929 fibroblast and adhesion of hFOB cell were investigated via AlamarBlue® (AB) assay and SEM respectively. All results were compared with BCP without Si substitution. Results showed that the presence of Si affected the material’s surface and morphology, cell proliferation and cell adhesion. AFM and SEM of Si-BCP revealed a rougher surface compared to BCP. Bioactivity in simulated body fluid (SBF) was characterised by pH, weight gain and apatite mineralisation on the sample surface whereby the changes in surface morphology were evaluated using SEM. Immersion in SBF up to 21 days indicated significant changes in pH, weight gain and apatite formation. Cell viability has demonstrated no cytotoxic effect and denoted that Si-BCP promoted good initial cell adhesion and proliferation. These results suggest that Si

  15. Effect of Bioactive Materials Modified with Chondroitin Sulfate on Human MSC =

    NASA Astrophysics Data System (ADS)

    De La Torre Torres, Jessica Elizabeth

    In this project chondroitin sulfate (CS) and growth factors were studied for their effect on hMSC in biomaterials. First, the effect of these biomolecules was tested in solution. Then, two kinds of biomaterials were created: bioactive surfaces for enhancing bioactivity of implantable devices and bioactive hydrogels which can be used as 3D scaffolds for cell encapsulation and delivery. A pro-survival effect of the growth factors studied in this project (epidermal growth factor, vascular endothelial growth factor and fibroblast growth factor) was not observed when tested in solution, therefore the project further focused on CS effect only. Interestingly, CS did not affect cell growth in media containing serum, while inducing cell detachment from substrate in serum free conditions. For the bioactive surfaces construction, CS was grafted to either an amine-rich plasmapolymerized coating created on polyethylene terephthalate (PET) films (further referred as LP) or to commercial cell culture plates functionalized with amino groups. The bioactive surfaces were characterized by different techniques such as contact angle, atomic force microscopy, Orange II dye and Toluidine Blue O dye colorimetric assays (for amino group and CS quantification respectively) and finally, cell culture experiments (adhesion, growth and survival). Results confirmed the presence of CS grafted on both substrates. Commercial amine plates grafted almost five times more CS compared to LP. This rendered the surface antifouling for proteins and cells as confirmed by protein adsorption and cell culture assays. Cell culture assays on bioactive surfaces based on LP demonstrated improved cell adhesion and growth when compared to tissue culture plates or bare PET films in serum containing conditions. Chitosan based hydrogels containing CS at a concentration of 500 mug/ml resulted in a cohesive hydrogel which supported hMSC viability up to 7 days. However increasing CS concentration to high level such as

  16. Flavonoid-modified surfaces: multifunctional bioactive biomaterials with osteopromotive, anti-inflammatory, and anti-fibrotic potential.

    PubMed

    Córdoba, Alba; Satué, María; Gómez-Florit, Manuel; Hierro-Oliva, Margarita; Petzold, Christiane; Lyngstadaas, Staale P; González-Martín, María Luisa; Monjo, Marta; Ramis, Joana M

    2015-03-11

    Flavonoids are small polyphenolic molecules of natural origin with antioxidant, anti-inflammatory, and antibacterial properties. Here, a bioactive surface based on the covalent immobilization of flavonoids taxifolin and quercitrin on titanium substrates is presented, using (3-aminopropyl)triethoxysilane (APTES) as coupling agent. FTIR and XPS measurements confirm the grafting of the flavonoids to the surfaces. Using 2-aminoethyl diphenylborinate (DPBA, a flavonoid-specific dye), the modified surfaces are imaged by fluorescence microscopy. The bioactivity of the flavonoid-modified surfaces is evaluated in vitro with human umbilical cord derived mesenchymal stem cells (hUC-MSCs) and human gingival fibroblasts (HGFs) and compared to that of simple flavonoid coatings prepared by drop casting. Flavonoid-modified surfaces show anti-inflammatory and anti-fibrotic potential on HGF. In addition, Ti surfaces covalently functionalized with flavonoids promote the differentiation of hUC-MSCs to osteoblasts--enhancing the expression of osteogenic markers, increasing alkaline phosphatase activity and calcium deposition; while drop-casted surfaces do not. These findings could have a high impact in the development of advanced implantable medical devices like bone implants. Given the broad range of bioactivities of flavonoid compounds, these surfaces are ready to be explored for other biomedical applications, e.g., as stent surface or tumor-targeted functionalized nanoparticles for cardiovascular or cancer therapies.

  17. The composition of potentially bioactive triterpenoid glycosides in red raspberry is influenced by tissue, extraction procedure and genotype.

    PubMed

    McDougall, Gordon J; Allwood, J William; Pereira-Caro, Gema; Brown, Emma M; Latimer, Cheryl; Dobson, Gary; Stewart, Derek; Ternan, Nigel G; Lawther, Roger; O'Connor, Gloria; Rowland, Ian; Crozier, Alan; Gill, Chris I R

    2017-09-08

    The beneficial effects of consumption of berry fruits on a range of chronic diseases has been attributed (at least in part) to the presence of unique phytochemicals. Recently, we identified novel ursolic acid-based triterpenoid glycosides (TTPNs) in raspberry fruit and demonstrated their survival in human ileal fluids after feeding which confirmed their colon-availability in vivo. In this paper, in vitro digestion studies demonstrated that certain TTPNs were stable under gastrointestinal conditions and confirmed that these components may have been responsible for bioactivity noted in previous studies. Sequential extractions of raspberry puree, isolated seeds and unseeded puree showed that certain TTPN components (e.g. peak T1 m/z 679, and T2 m/z 1358) had different extractabilities in water/solvent mixes and were differentially associated with the seeds. Purified seed TTPNs (mainly T1 and T2) were shown to be anti-genotoxic in HT29 and CCD841 cell based in vitro colonocyte models. Further work confirmed that the seeds contained a wider range of TTPN-like components which were also differentially extractable in water/solvent mixes. This differential extractability could influence the TTPN composition and potential bioactivity of the extracts. There was considerable variation in total content of TTPNs (∼3-fold) and TTPN composition across 13 Rubus genotypes. Thus, TTPNs are likely to be present in raspberry juices and common extracts used for bioactivity studies and substantial variation exists in both content and composition due to genetics, tissue source or extraction conditions, which may all affect observed bioactivity.

  18. Enzymatic synthesis of bioactive compounds with high potential for cosmeceutical application.

    PubMed

    Antonopoulou, Io; Varriale, Simona; Topakas, Evangelos; Rova, Ulrika; Christakopoulos, Paul; Faraco, Vincenza

    2016-08-01

    Cosmeceuticals are cosmetic products containing biologically active ingredients purporting to offer a pharmaceutical therapeutic benefit. The active ingredients can be extracted and purified from natural sources (botanicals, herbal extracts, or animals) but can also be obtained biotechnologically by fermentation and cell cultures or by enzymatic synthesis and modification of natural compounds. A cosmeceutical ingredient should possess an attractive property such as anti-oxidant, anti-inflammatory, skin whitening, anti-aging, anti-wrinkling, or photoprotective activity, among others. During the past years, there has been an increased interest on the enzymatic synthesis of bioactive esters and glycosides based on (trans)esterification, (trans)glycosylation, or oxidation reactions. Natural bioactive compounds with exceptional theurapeutic properties and low toxicity may offer a new insight into the design and development of potent and beneficial cosmetics. This review gives an overview of the enzymatic modifications which are performed currently for the synthesis of products with attractive properties for the cosmeceutical industry.

  19. Thiol modification by bioactivated polyphenols and its potential role in skin inflammation.

    PubMed

    Nakamura, Yoshimasa; Ishii, Takeshi; Abe, Naomi; Murata, Yoshiyuki

    2014-01-01

    In the present study, we evaluated the modifying behavior of simple phenolic compounds on the sulfhydryl groups of glutathione and proteins. The catechol-type polyphenols, including protocatechuic acid, but neither the monophenols nor O-methylated catechol, can modify the sulfhydryl groups in a phenol oxidase-dependent manner. The possible involvement of polyphenol bioactivation in the enhancement of skin inflammation was also suggested.

  20. Bioactivity of freeze-dried platelet-rich plasma in an adsorbed form on a biodegradable polymer material.

    PubMed

    Nakajima, Yu; Kawase, Tomoyuki; Kobayashi, Mito; Okuda, Kazuhiro; Wolff, Larry F; Yoshie, Hiromasa

    2012-01-01

    Owing to the necessity for the immediate preparation from patients' blood, autologous platelet-rich plasma (PRP) limits its clinical applicability. To address this concern and respond to emergency care and other unpredictable uses, we have developed a freeze-dried PRP in an adsorbed form on a biodegradable polymer material (Polyglactin 910). On the polymer filaments of PRP mesh, which was prepared by coating the polymer mesh with human fresh PRP and subsequent freeze-drying, platelets were incorporated, and related growth factors were preserved at high levels. This new PRP mesh preparation significantly and reproducibly stimulated the proliferation of human periodontal ligament cells in vitro and neovascularization in a chorioallantoic membrane assay. A full-thickness skin defect model in a diabetic mouse demonstrated the PRP mesh, although prepared from human blood, substantially facilitated angiogenesis, granulation tissue formation, and re-epithelialization without inducing severe inflammation in vivo. These data demonstrate that our new PRP mesh preparation functions as a bioactive material to facilitate tissue repair/regeneration. Therefore, we suggest that this bioactive material, composed of allogeneic PRP, could be clinically used as a promising alternative in emergency care or at times when autologous PRP is not prepared immediately before application.

  1. Biotechnological potential of endophytic actinomycetes associated with Asteraceae plants: isolation, biodiversity and bioactivities.

    PubMed

    Tanvir, Rabia; Sajid, Imran; Hasnain, Shahida

    2014-04-01

    Endophytic actinomycetes from five Asteraceae plants were isolated and evaluated for their bioactivities. From Parthenium hysterophorus, Ageratum conyzoides, Sonchus oleraceus, Sonchus asper and Hieracium canadense, 42, 45, 90, 3, and 2 isolates, respectively, were obtained. Of the isolates, 86 (47.2 %) showed antimicrobial activity. Majority of the isolates were recovered from the roots (n = 127, 69.7 %). The dominant genus was Streptomyces (n = 96, 52.7 %), while Amycolatopsis, Pseudonocardia, Nocardia and Micromonospora were also recovered. Overall, 36 of the 86 isolates were significantly bioactivity while 18 (20.9 %) showed strong bioactivity. In total, 52.1 and 66.6 % showed potent cytotoxicity and antioxidant activities. The LC50 for 15 strains was <20 μg/ml. Compared to the ascorbate standard (EC50 0.34 μg/ml), all isolates gave impressive results with notable EC50 values of 0.65, 0.67, 0.74 and 0.79 μg/ml.

  2. Bioactivity and chemical characterization of Opuntia macrorhiza Engelm. seed oil: potential food and pharmaceutical applications.

    PubMed

    Chahdoura, Hassiba; Barreira, João C M; Adouni, Khawla; Mhadhebi, Lamia; Calhelha, Ricardo C; Snoussi, Mejdi; Majdoub, Hatem; Flamini, Guido; Ferreira, Isabel C F R; Achour, Lotfi

    2017-08-01

    In the food industry, there is a continuous search for ingredients that might provide advantageous properties to food products, either considering their nutritional value or bioactivity, as well as flavouring and technological aspects. Crude oils are good examples of this type of ingredient, especially if obtained from nonconventional sources. Accordingly, the Opuntia macrorhiza Engelm. seed oil (OMSO) was chemically characterized and evaluated for different in vitro and in vivo bioactivities. OMSO presented physicochemical characteristics appropriate to be considered as an edible oil, namely low acidity value, stability to oxidation (high peroxide value and low K232 and K270 values), and high contents of unsaturated fatty acids (as shown by the iodine value) and saponifiable matter. Furthermore, this natural oil, owing to its rich phytochemical profile, showed relevant antioxidant activity (especially in lipid peroxidation inhibition assays), α-glucosidase inhibitory activity, cytotoxicity against human tumour cell lines, antibacterial (mainly against Gram positive species) and antifungal properties, as well as anti-inflammatory and analgesic activities. Furthermore, OMSO did not show any sign of acute toxicity on animals, highlighting its possible use in different applications, considering that this natural product is not expected to induce the adverse effects typically associated with synthetic bioactive agents (e.g., ampicillin, amphotericin B, or lysine acetylsalicilate).

  3. An ethnobotanical survey of medicinal plants of Laos toward the discovery of bioactive compounds as potential candidates for pharmaceutical development

    PubMed Central

    Soejarto, D.D.; Gyllenhaal, C.; Kadushin, M.R.; Southavong, B.; Sydara, K.; Bouamanivong, S.; Xaiveu, M.; Zhang, H.-J.; Franzblau, S.G.; Tan, Ghee T.; Pezzuto, J.M.; Riley, M.C.; Elkington, B.G.; Waller, D.P.

    2012-01-01

    Context An ethnobotany-based approach in the selection of raw plant materials to study was implemented. Objective To acquire raw plant materials using ethnobotanical field interviews as starting point to discover new bioactive compounds from medicinal plants of the Lao People’s Democratic Republic. Methods Using semi-structured field interviews with healers in the Lao PDR, plant samples were collected, extracted, and bio-assayed to detect bioactivity against cancer, HIV/AIDS, TB, malaria. Plant species demonstrating activity were recollected and the extracts subjected to a bioassay-guided isolation protocol to isolate and identify the active compounds. Results Field interviews with 118 healers in 15 of 17 provinces of Lao PDR yielded 753 collections (573 species) with 955 plant samples. Of these 955, 50 extracts demonstrated activity in the anticancer, 10 in the anti-HIV, 30 in the anti-TB, and 52 in the antimalarial assay. Recollection of actives followed by bioassay-guided isolation processes yielded a series of new and known in vitro-active anticancer and antimalarial compounds from 5 species. Discussion Laos has a rich biodiversity, harboring an estimated 8000–11,000 species of plants. In a country highly dependent on traditional medicine for its primary health care, this rich plant diversity serves as a major source of their medication. Conclusions Ethnobotanical survey has demonstrated the richness of plant-based traditional medicine of Lao PDR, taxonomically and therapeutically. Biological assays of extracts of half of the 955 samples followed by in-depth studies of a number of actives have yielded a series of new bioactive compounds against the diseases of cancer and malaria. PMID:22136442

  4. Evaluating the capacity to generate and preserve nitric oxide bioactivity in highly purified earthworm erythrocruorin: a giant polymeric hemoglobin with potential blood substitute properties.

    PubMed

    Roche, Camille J; Talwar, Abhinav; Palmer, Andre F; Cabrales, Pedro; Gerfen, Gary; Friedman, Joel M

    2015-01-02

    The giant extracellular hemoglobin (erythrocruorin) from the earth worm (Lumbricus terrestris) has shown promise as a potential hemoglobin-based oxygen carrier (HBOC) in in vivo animal studies. An important beneficial characteristic of this hemoglobin (LtHb) is the large number of heme-based oxygen transport sites that helps overcome issues of osmotic stress when attempting to provide enough material for efficient oxygen delivery. A potentially important additional property is the capacity of the HBOC either to generate nitric oxide (NO) or to preserve NO bioactivity to compensate for decreased levels of NO in the circulation. The present study compares the NO-generating and NO bioactivity-preserving capability of LtHb with that of human adult hemoglobin (HbA) through several reactions including the nitrite reductase, reductive nitrosylation, and still controversial nitrite anhydrase reactions. An assignment of a heme-bound dinitrogen trioxide as the stable intermediate associated with the nitrite anhydrase reaction in both LtHb and HbA is supported based on functional and EPR spectroscopic studies. The role of the redox potential as a factor contributing to the NO-generating activity of these two proteins is evaluated. The results show that LtHb undergoes the same reactions as HbA and that the reduced efficacy for these reactions for LtHb relative to HbA is consistent with the much higher redox potential of LtHb. Evidence of functional heterogeneity in LtHb is explained in terms of the large difference in the redox potential of the isolated subunits.

  5. Perspective and potential of smart optical materials

    NASA Astrophysics Data System (ADS)

    Choi, Sang H.; Duzik, Adam J.; Kim, Hyun-Jung; Park, Yeonjoon; Kim, Jaehwan; Ko, Hyun-U.; Kim, Hyun-Chan; Yun, Sungryul; Kyung, Ki-Uk

    2017-09-01

    The increasing requirements of hyperspectral imaging optics, electro/photo-chromic materials, negative refractive index metamaterial optics, and miniaturized optical components from micro-scale to quantum-scale optics have all contributed to new features and advancements in optics technology. Development of multifunctional capable optics has pushed the boundaries of optics into new fields that require new disciplines and materials to maximize the potential benefits. The purpose of this study is to understand and show the fundamental materials and fabrication technology for field-controlled spectrally active optics (referred to as smart optics) that are essential for future industrial, scientific, military, and space applications, such as membrane optics, filters, windows for sensors and probes, telescopes, spectroscopes, cameras, light valves, light switches, and flat-panel displays. The proposed smart optics are based on the Stark and Zeeman effects in materials tailored with quantum dot arrays and thin films made from readily polarizable materials via ferroelectricity or ferromagnetism. Bound excitonic states of organic crystals are also capable of optical adaptability, tunability, and reconfigurability. To show the benefits of smart optics, this paper reviews spectral characteristics of smart optical materials and device technology. Experiments testing the quantum-confined Stark effect, arising from rare earth element doping effects in semiconductors, and applied electric field effects on spectral and refractive index are discussed. Other bulk and dopant materials were also discovered to have the same aspect of shifts in spectrum and refractive index. Other efforts focus on materials for creating field-controlled spectrally smart active optics on a selected spectral range. Surface plasmon polariton transmission of light through apertures is also discussed, along with potential applications. New breakthroughs in micro scale multiple zone plate optics as a micro

  6. Screening of six Ayurvedic medicinal plants for anti-obesity potential: An investigation on bioactive constituents from Oroxylum indicum (L.) Kurz bark.

    PubMed

    Mangal, Priyanka; Khare, Pragyanshu; Jagtap, Sneha; Bishnoi, Mahendra; Kondepudi, Kanthi Kiran; Bhutani, Kamlesh Kumar

    2017-02-02

    As an effort to identify newer anti-obesity lead(s) we have selected 13 plant materials from the six plant species which have been reported in Indian Ayurvedic medicine as remedy against complications affecting glucose and lipid homeostasis. In vitro screening of six Indian Ayurvedic medicinal plants on anti-adipogenic and pancreatic lipase (PL) inhibition potential followed by bioactivity guided isolation from most active plant material. In vitro anti-adipogenic assay using 3T3-L1 preadipocytes and pancreatic lipase (PL) inhibition assay were performed for hexanes, dichloromethane, ethyl acetate and methanolic extracts of all the plant materials. Bioactivity guided isolation approach was used to identify active constituent for anti-adipogenesis and PL inhibition assay. Inhibition of lipid accumulation and adipogenic transcription factor was measured by oil Red 'O' staining and quantitative real-time PCR method respectively. Ethyl acetate extract of Oroxylum indicum bark was found to be most active in screening of anti-adipogenesis (59.12±1.66% lipid accumulation as compared to control at 50μg/mL dose) and PL inhibition (89.12±6.87% PL inhibition at 250μg/mL dose) assays. Further, three bioactive flavonoids were isolated and identified as oroxylin A, chrysin and baicalein from O. indicum bark. Oroxylin A, chrysin, and baicalein were inhibited lipid accumulation in 3T3-L1 preadipocytes (75.00±5.76%, 70.21±4.23% and 77.21±5.49% lipid accumulation respectively in comparison to control at 50μM dose) and PL enzyme (69.86±2.96%, 52.08±2.14% and 45.06±2.42% PL inhibition respectively at 250μg/mL dose). In addition, oroxylin A and chrysin also inhibited PPARγ and C/EBPα, major adipogenic transcription factors, in 3T3L-1 preadipocytes during adipogenesis process at 50μM dose. The present study augurs the anti-obesity potential of well practiced Ayurvedic herb O. indicum and its flavonoids. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Potential Pharmacological Resources: Natural Bioactive Compounds from Marine-Derived Fungi

    PubMed Central

    Jin, Liming; Quan, Chunshan; Hou, Xiyan; Fan, Shengdi

    2016-01-01

    In recent years, a considerable number of structurally unique metabolites with biological and pharmacological activities have been isolated from the marine-derived fungi, such as polyketides, alkaloids, peptides, lactones, terpenoids and steroids. Some of these compounds have anticancer, antibacterial, antifungal, antiviral, anti-inflammatory, antioxidant, antibiotic and cytotoxic properties. This review partially summarizes the new bioactive compounds from marine-derived fungi with classification according to the sources of fungi and their biological activities. Those fungi found from 2014 to the present are discussed. PMID:27110799

  8. Microwave processing of lunar materials: potential applications

    SciTech Connect

    Meek, T.T.; Cocks, F.H.; Vaniman, D.T.; Wright, R.A.

    1984-01-01

    The microwave processing of lunar materials holds promise for the production of either water, oxygen, primary metals, or ceramic materials. Extra high frequency microwave (EHF) at between 100 and 500 gigahertz have the potential for selective coupling to specific atomic species and a concomitant low energy requirement for the extraction of specific materials, such as oxygen, from lunar ores. The coupling of ultra high frequency (UHF) (e.g., 2.45 gigahertz) microwave frequencies to hydrogen-oxygen bonds might enable the preferential and low energy cost removal (as H/sub 2/O) of implanted protons from the sun or of adosrbed water which might be found in lunar dust in permanently shadowed polar areas. Microwave melting and selective phase melting of lunar materials could also be used either in the preparation of simplified ceramic geometries (e.g., bricks) with custom-tailored microstructures, or for the direct preparation of hermetic walls in underground structures. Speculatively, the preparation of photovoltaic devices based on lunar materials, especially ilmenite, may be a potential use of microwave processing on the moon. Preliminary experiments on UHF melting of terrestrial basalt, basalt/ilmenite and mixtures show that microwave processing is feasible.

  9. The physicochemical characterization and in vivo response of micro/nanoporous bioactive ceramic particulate bone graft materials.

    PubMed

    Tovar, Nick; Jimbo, Ryo; Witek, Lukasz; Anchieta, Rodolfo; Yoo, Daniel; Manne, Lakshmipradha; Machado, Lucas; Gangolli, Riddhi; Coelho, Paulo G

    2014-10-01

    In this study, the physicochemical characteristics of calcium phosphate based bioactive ceramics of different compositions and blends presenting similar micro/nanoporosity and micrometer scale surface texture were characterized and evaluated in an in vivo model. Prior to the animal experiment, the porosity, surface area, particle size distribution, phase quantification, and dissolution of the materials tested were evaluated. The bone regenerative properties of the materials were evaluated using a rabbit calvaria model. After 2, 4, and 8 weeks, the animals were sacrificed and all samples were subjected to histologic observation and histomorphometric analysis. The material characterization showed that all materials tested presented variation in particle size, porosity and composition with different degrees of HA/TCP/lower stoichiometry phase ratios. Histologically, the calvarial defects presented temporal bone filling suggesting that all material groups were biocompatible and osteoconductive. Among the different materials tested, there were significant differences found in the amount of bone formation as a function of time. At 8 weeks, the micro/nanoporous material presenting ~55%TCP:45%HA composition ratio presented higher amounts of new bone regeneration relative to other blends and a decrease in the amount of soft tissue infiltration. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Antidiabetic potential of bioactive molecules coated chitosan nanoparticles in experimental rats.

    PubMed

    Perumal, Venkatachalam; Manickam, Thiyagarajan; Bang, Keuk-Soo; Velmurugan, Palanivel; Oh, Byung-Taek

    2016-11-01

    The present study was carried out to examine the antidiabetic effects of chitosan nanoparticles (CNPs) loaded with (Stevia rebaudiana leaf extract-SRLE) bioactive molecules in a rat model of streptozotocin (STZ) induced diabetes mellitus. Successful crosslinking of the bioactive molecules to the chitosan nanoparticles was confirmed by Fourier Transform Infrared Spectroscopy (FTIR). The colloidal characteristics of the synthesized nanoparticles were revealed by X-ray Diffraction (XRD) analysis. Morphological analysis by Transmission Electron Microscopy (TEM) revealed that thebioactive molecule-loaded CNPs were well-dispersed and spherical or polygonal in shape with an average size of<73.27nm than the z-average value (327nm) as measured by Dynamic Light Scattering (DLS). SRLE CNP-treated diabetic rats showed a significant reduction in their mean fasting blood glucose level compared with the diabetic control group. The serum levels of various enzymes viz., serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), alkaline phosphatases (ALP), lipid peroxidation, and antioxidant such as catalase (CAT), reduced glutathione (GSH), and superoxide dismutase (SOD) in the SRLE CNP-treated group were closer to normal levels than those in the diabetic control group. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Arabinogalactan present in the mountain celery seed extract potentiated hypolipidemic bioactivity of coexisting polyphenols in hamsters.

    PubMed

    Lin, Li-Yun; Ker, Yaw-Bee; Chang, Chi-Huan; Chen, Kuan-Chou; Peng, Robert Y

    2011-03-01

    Previously, we showed the essential oils (EO) of the mountain celery [Cryptotaenia japonica Hass (Umbelliferae)] seeds (MCS) to be a prominent hypolipidemic agent. We hypothesized the aqueous extract (AE) of its seeds could also exhibit a comparable nutritional effect. Experiments were carried out for compositional analysis, antioxidant assay, and hypolipidaemic assay with AE in hamsters. AE contained soluble arabinogalactan (AGal) with molecular weight (MW) 878 kDa. AE also was enriched in polyphenolics and flavonoids, reaching 30.4 and 2.20 mg/100 g, respectively. AGal consisted of eight monosaccharides (in mols %), galactose (28.75), arabinose (24.84), glucose (17.91), mannose (6.93), ribose (6.03), fucose (5.83), xylose (5.30), and rhamnose (4.41), with average MW 878 kDa. In vitro, AE showed potent ferrous chelating and DPPH scavenging effects but only moderate H₂O₂ scavenging capability. In hamsters, AE exhibited promising hypolipidemic bioactivity, in particular, the HDL-C and hepatic unsaturated fatty acid (UFA) biosynthesis regarding oleic, linoleic, and arachidonic acids. The presence of AGal enhanced the hypolipidemic and antioxidative bioactivity of MCS. MCS is feasibly beneficial to the hepatic de novo UFA synthesis and the hypolipidemics as evidenced by hamster model.

  12. The potentiality of cross-linked fungal chitosan to control water contamination through bioactive filtration.

    PubMed

    Tayel, Ahmed A; El-Tras, Wael F; Elguindy, Nihal M

    2016-07-01

    Water contamination, with heavy metals and microbial pathogens, is among the most dangerous challenges that confront human health worldwide. Chitosan is a bioactive biopolymer that could be produced from fungal mycelia to be utilized in various applied fields. An attempt to apply fungal chitosan for heavy metals chelation and microbial pathogens inhibition, in contaminated water, was performed in current study. Chitosan was produced from the mycelia of Aspergillus niger, Cunninghamella elegans, Mucor rouxii and from shrimp shells, using unified production conditions. The FT-IR spectra of produced chitosans were closely comparable. M. rouxii chitosan had the highest deacetylation degree (91.3%) and the lowest molecular weight (33.2kDa). All chitosan types had potent antibacterial activities against Escherichia coli and Staphylococcus aureus; the most forceful type was C. elegans chitosan. Chitosan beads were cross-linked with glutaraldehyde (GLA) and ethylene-glycol-diglycidyl ether (EGDE); linked beads became insoluble in water, acidic and alkaline solutions and could effectively adsorb heavy metals ions, e.g. copper, lead and zinc, in aqueous solution. The bioactive filter, loaded with EGDE- A. niger chitosan beads, was able to reduce heavy metals' concentration with >68%, and microbial load with >81%, after 6h of continuous water flow in the experimentally designed filter. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Toxic Potential of Materials at the Nanolevel

    NASA Astrophysics Data System (ADS)

    Nel, Andre; Xia, Tian; Mädler, Lutz; Li, Ning

    2006-02-01

    Nanomaterials are engineered structures with at least one dimension of 100 nanometers or less. These materials are increasingly being used for commercial purposes such as fillers, opacifiers, catalysts, semiconductors, cosmetics, microelectronics, and drug carriers. Materials in this size range may approach the length scale at which some specific physical or chemical interactions with their environment can occur. As a result, their properties differ substantially from those bulk materials of the same composition, allowing them to perform exceptional feats of conductivity, reactivity, and optical sensitivity. Possible undesirable results of these capabilities are harmful interactions with biological systems and the environment, with the potential to generate toxicity. The establishment of principles and test procedures to ensure safe manufacture and use of nanomaterials in the marketplace is urgently required and achievable.

  14. Fucoidan improves bioactivity and vasculogenic potential of mesenchymal stem cells in murine hind limb ischemia associated with chronic kidney disease.

    PubMed

    Lee, Jun Hee; Ryu, Jung Min; Han, Yong-Seok; Zia, Mohammad Farid; Kwon, Hyog Young; Noh, Hyunjin; Han, Ho Jae; Lee, Sang Hun

    2016-08-01

    Chronic kidney disease (CKD) is a significant risk factor for cardiovascular and peripheral vascular disease. Although mesenchymal stem cell (MSC)-based therapy is a promising strategy for treatment of ischemic diseases associated with CKD, the associated pathophysiological conditions lead to low survival and proliferation of transplanted MSCs. To address these limitations, we investigated the effects of fucoidan, a sulfated polysaccharide, on the bioactivity of adipose tissue-derived MSCs and the potential of fucoidan-treated MSCs to improve neovascularization in ischemic tissues of CKD mice. Treatment of MSCs with fucoidan increased their proliferative potential and the expression of cell cycle-associated proteins, such as cyclin E, cyclin dependent kinase (CDK) 2, cyclin D1, and CDK4, via focal adhesion kinase and the phosphatidylinositol-4,5-bisphosphate 3-kinase-Akt axis. Moreover, fucoidan enhanced the immunomodulatory activity of MSCs through the ERK-IDO-1 signal cascade. Fucoidan was found to augment the proliferation, incorporation, and endothelial differentiation of transplanted MSCs at ischemic sites in CKD mice hind limbs. In addition, transplantation of fucoidan-treated MSCs enhanced the ratio of blood flow and limb salvage in CKD mice with hind limb ischemia. To our knowledge, our findings are the first to reveal that fucoidan enhances the bioactivity of MSCs and improves their neovascularization in ischemic injured tissues of CKD. In conclusion, fucoidan-treated MSCs may provide an important pathway toward therapeutic neovascularization in patients with CKD.

  15. Potential Applications of Biotechnology to Aerospace Materials.

    DTIC Science & Technology

    1986-11-01

    from low - grade ores and industrial wastes. Other organisms that have demonstrated ability to solu- bilize metals include heterotrophic bacteria, molds...cadmium, scandium, erbium, yttrium, and titanium. The potential advantage of biomining is the ability to concentrate metals from low - grade materials...organisms and/ or biological molecules to produce or aid in production of a commercial product. This is a broad definition of a relatively young

  16. The Biomineralization of a Bioactive Glass-Incorporated Light-Curable Pulp Capping Material Using Human Dental Pulp Stem Cells

    PubMed Central

    Jun, Soo-Kyung; Lee, Hae-Hyoung

    2017-01-01

    The aim of this study was to investigate the biomineralization of a newly introduced bioactive glass-incorporated light-curable pulp capping material using human dental pulp stem cells (hDPSCs). The product (Bioactive® [BA]) was compared with a conventional calcium hydroxide-incorporated (Dycal [DC]) and a light-curable (Theracal® [TC]) counterpart. Eluates from set specimens were used for investigating the cytotoxicity and biomineralization ability, determined by alkaline phosphatase (ALP) activity and alizarin red staining (ARS). Cations and hydroxide ions in the extracts were measured. An hDPSC viability of less than 70% was observed with 50% diluted extract in all groups and with 25% diluted extract in the DC. Culturing with 12.5% diluted BA extract statistically lowered ALP activity and biomineralization compared to DC (p < 0.05), but TC did not (p > 0.05). Ca (~110 ppm) and hydroxide ions (pH 11) were only detected in DC and TC. Ionic supplement-added BA, which contained similar ion concentrations as TC, showed similar ARS mineralization compared to TC. In conclusion, the BA was similar to, yet more cytotoxic to hDPSCs than, its DC and TC. The BA was considered to stimulate biomineralization similar to DC and TC only when it released a similar amount of Ca and hydroxide ions. PMID:28232937

  17. The Biomineralization of a Bioactive Glass-Incorporated Light-Curable Pulp Capping Material Using Human Dental Pulp Stem Cells.

    PubMed

    Jun, Soo-Kyung; Lee, Jung-Hwan; Lee, Hae-Hyoung

    2017-01-01

    The aim of this study was to investigate the biomineralization of a newly introduced bioactive glass-incorporated light-curable pulp capping material using human dental pulp stem cells (hDPSCs). The product (Bioactive® [BA]) was compared with a conventional calcium hydroxide-incorporated (Dycal [DC]) and a light-curable (Theracal® [TC]) counterpart. Eluates from set specimens were used for investigating the cytotoxicity and biomineralization ability, determined by alkaline phosphatase (ALP) activity and alizarin red staining (ARS). Cations and hydroxide ions in the extracts were measured. An hDPSC viability of less than 70% was observed with 50% diluted extract in all groups and with 25% diluted extract in the DC. Culturing with 12.5% diluted BA extract statistically lowered ALP activity and biomineralization compared to DC (p < 0.05), but TC did not (p > 0.05). Ca (~110 ppm) and hydroxide ions (pH 11) were only detected in DC and TC. Ionic supplement-added BA, which contained similar ion concentrations as TC, showed similar ARS mineralization compared to TC. In conclusion, the BA was similar to, yet more cytotoxic to hDPSCs than, its DC and TC. The BA was considered to stimulate biomineralization similar to DC and TC only when it released a similar amount of Ca and hydroxide ions.

  18. C-Glycopyranosyl Arenes and Hetarenes: Synthetic Methods and Bioactivity Focused on Antidiabetic Potential.

    PubMed

    Bokor, Éva; Kun, Sándor; Goyard, David; Tóth, Marietta; Praly, Jean-Pierre; Vidal, Sébastien; Somsák, László

    2017-02-08

    This Review summarizes close to 500 primary publications and surveys published since 2000 about the syntheses and diverse bioactivities of C-glycopyranosyl (het)arenes. A classification of the preparative routes to these synthetic targets according to methodologies and compound categories is provided. Several of these compounds, regardless of their natural or synthetic origin, display antidiabetic properties due to enzyme inhibition (glycogen phosphorylase, protein tyrosine phosphatase 1B) or by inhibiting renal sodium-dependent glucose cotransporter 2 (SGLT2). The latter class of synthetic inhibitors, very recently approved as antihyperglycemic drugs, opens new perspectives in the pharmacological treatment of type 2 diabetes. Various compounds with the C-glycopyranosyl (het)arene motif were subjected to biological studies displaying among others antioxidant, antiviral, antibiotic, antiadhesive, cytotoxic, and glycoenzyme inhibitory effects.

  19. Vibrational study on the bioactivity of Portland cement-based materials for endodontic use

    NASA Astrophysics Data System (ADS)

    Taddei, P.; Tinti, A.; Gandolfi, M. G.; Rossi, P. L.; Prati, C.

    2009-04-01

    The bioactivity of a modified Portland cement (wTC) and a phosphate-doped wTC cement (wTC-P) was studied at 37 °C in Dulbecco's Phosphate Buffered Saline (DPBS). The cements, prepared as disks, were analysed at different ageing times (from 1 day to 2 months) by micro-Raman and ATR/FT-IR spectroscopies. The presence of deposits on the surface of the cements and the composition changes as a function of the storage time were investigated. The presence of an apatite deposit on the surface of both cements was already revealed after one day of ageing in DPBS. The trend of the I 965/I 991 Raman intensity ratio indicated the formation of a meanly thicker apatite deposit on the wTC-P cement at all the investigated times. This result was confirmed by the trend of the I 1030/I 945 IR intensity ratio calculated until 14 days of ageing. At 2 months, the thickness of the apatite deposit on wTC and wTC-P was about 200 and 500 μm, respectively, as estimated by micro-Raman spectroscopy, confirming the higher bioactivity of the phosphate-doped cement. Vibrational techniques allowed to gain more insights into the cement transformation and the different hydration rates of the various cement component. The setting of the cement and the formation of the hydrated silicate gel (C-S-H phase) was spectroscopically monitored through the I 830/I 945 IR intensity ratio.

  20. Potential effects of gallium on cladding materials

    SciTech Connect

    Wilson, D.F.; Beahm, E.C.; Besmann, T.M.; DeVan, J.H.; DiStefano, J.R.; Gat, U.; Greene, S.R.; Rittenhouse, P.L.; Worley, B.A.

    1997-10-01

    This paper identifies and examines issues concerning the incorporation of gallium in weapons derived plutonium in light water reactor (LWR) MOX fuels. Particular attention is given to the more likely effects of the gallium on the behavior of the cladding material. The chemistry of weapons grade (WG) MOX, including possible consequences of gallium within plutonium agglomerates, was assessed. Based on the calculated oxidation potentials of MOX fuel, the effect that gallium may have on reactions involving fission products and possible impact on cladding performance were postulated. Gallium transport mechanisms are discussed. With an understanding of oxidation potentials and assumptions of mechanisms for gallium transport, possible effects of gallium on corrosion of cladding were evaluated. Potential and unresolved issues and suggested research and development (R and D) required to provide missing information are presented.

  1. Cheese whey: A potential resource to transform into bioprotein, functional/nutritional proteins and bioactive peptides.

    PubMed

    Yadav, Jay Shankar Singh; Yan, Song; Pilli, Sridhar; Kumar, Lalit; Tyagi, R D; Surampalli, R Y

    2015-11-01

    The byproduct of cheese-producing industries, cheese whey, is considered as an environmental pollutant due to its high BOD and COD concentrations. The high organic load of whey arises from the presence of residual milk nutrients. As demand for milk-derived products is increasing, it leads to increased production of whey, which poses a serious management problem. To overcome this problem, various technological approaches have been employed to convert whey into value-added products. These technological advancements have enhanced whey utilization and about 50% of the total produced whey is now transformed into value-added products such as whey powder, whey protein, whey permeate, bioethanol, biopolymers, hydrogen, methane, electricity bioprotein (single cell protein) and probiotics. Among various value-added products, the transformation of whey into proteinaceous products is attractive and demanding. The main important factor which is attractive for transformation of whey into proteinaceous products is the generally recognized as safe (GRAS) regulatory status of whey. Whey and whey permeate are biotransformed into proteinaceous feed and food-grade bioprotein/single cell protein through fermentation. On the other hand, whey can be directly processed to obtain whey protein concentrate, whey protein isolate, and individual whey proteins. Further, whey proteins are also transformed into bioactive peptides via enzymatic or fermentation processes. The proteinaceous products have applications as functional, nutritional and therapeutic commodities. Whey characteristics, and its transformation processes for proteinaceous products such as bioproteins, functional/nutritional protein and bioactive peptides are covered in this review. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Need for accurate and standardized determination of amino acids and bioactive peptides for evaluating protein quality and potential health effects of foods and dietary supplements.

    PubMed

    Gilani, G Sarwar; Xiao, Chaowu; Lee, Nora

    2008-01-01

    Accurate standardized methods for the determination of amino acid in foods are required to assess the nutritional safety and compositional adequacy of sole source foods such as infant formulas and enteral nutritionals, and protein and amino acid supplements and their hydrolysates, and to assess protein claims of foods. Protein digestibility-corrected amino acid score (PDCAAS), which requires information on amino acid composition, is the official method for assessing protein claims of foods and supplements sold in the United States. PDCAAS has also been adopted internationally as the most suitable method for routine evaluation of protein quality of foods by the Food and Agriculture Organization/World Health Organization. Standardized methods for analysis of amino acids by ion-exchange chromatography have been developed. However, there is a need to develop validated methods of amino acid analysis in foods using liquid chromatographic techniques, which have replaced ion-exchange methods for quantifying amino acids in most laboratories. Bioactive peptides from animal and plant proteins have been found to potentially impact human health. A wide range of physiological effects, including blood pressure-lowering effects, cholesterol-lowering ability, antithrombotic effects, enhancement of mineral absorption, and immunomodulatory effects have been described for bioactive peptides. There is considerable commercial interest in developing functional foods containing bioactive peptides. There is also a need to develop accurate standardized methods for the characterization (amino acid sequencing) and quantification of bioactive peptides and to carry out dose-response studies in animal models and clinical trials to assess safety, potential allergenicity, potential intolerance, and efficacy of bioactive peptides. Information from these studies is needed for determining the upper safe levels of bioactive peptides and as the basis for developing potential health claims for bioactive

  3. Surface Modifications of Titanium Implants by Multilayer Bioactive Coatings with Drug Delivery Potential: Antimicrobial, Biological, and Drug Release Studies

    NASA Astrophysics Data System (ADS)

    Ordikhani, Farideh; Zustiak, Silviya Petrova; Simchi, Abdolreza

    2016-04-01

    Recent strategies to locally deliver antimicrobial agents to combat implant-associated infections—one of the most common complications in orthopedic surgery—are gaining interest. However, achieving a controlled release profile over a desired time frame remains a challenge. In this study, we present an innovative multifactorial approach to combat infections which comprises a multilayer chitosan/bioactive glass/vancomycin nanocomposite coating with an osteoblastic potential and a drug delivery capacity. The bioactive drug-eluting coating was prepared on the surface of titanium foils by a multistep electrophoretic deposition technique. The adopted deposition strategy allowed for a high antibiotic loading of 1038.4 ± 40.2 µg/cm2. The nanocomposite coating exhibited a suppressed burst release with a prolonged sustained vancomycin release for up to 6 weeks. Importantly, the drug release profile was linear with respect to time, indicating a zero-order release kinetics. An in vitro bactericidal assay against Staphylococcus aureus confirmed that releasing the drug reduced the risk of bacterial infection. Excellent biocompatibility of the developed coating was also demonstrated by in vitro cell studies with a model MG-63 osteoblast cell line.

  4. Effect of human adipose tissue-derived mesenchymal-stem-cell bioactive materials on porcine embryo development.

    PubMed

    Park, Hyo-Young; Kim, Eun-Young; Lee, Seung-Eun; Choi, Hyun-Yong; Moon, Jeremiah Jiman; Park, Min-Jee; Son, Yeo-Jin; Lee, Jun-Beom; Jeong, Chang-Jin; Lee, Dong-Sun; Riu, Key-Jung; Park, Se-Pill

    2013-12-01

    Human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) secrete bioactive materials that are beneficial for tissue repair and regeneration. In this study, we characterized human hAT-MSC bioactive material (hAT-MSC-BM), and examined the effect of hAT-MSC-BM on porcine embryo development. hAT-MSC-BM was enriched with several growth factors and cytokines, including fibroblast growth factor 2 (FGF2), vascular endothelial growth factor A (VEGFA), and interleukin 6 (IL6). Among the various concentrations and days of treatment tested, 10% hAT-MSC-BM treatment beginning on culture Day 4 provided the best environment for the in vitro growth of parthenogenetic porcine embryos. While the addition of 10% fetal bovine serum (FBS) increased the hatching rate and the total cell number of parthenogenetic porcine embryos compared with the control and hAT-MSC culture medium group, the best results were from the group cultured with 10% hAT-MSC-BM. Mitochondrial activity was also higher in the 10% hAT-MSC-BM-treated group. Moreover, the relative mRNA expression levels of development and anti-apoptosis genes were significantly higher in the 10% hAT-MSC-BM-treated group than in control, hAT-MSC culture medium, or 10% FBS groups, whereas the transcript abundance of an apoptosis gene was slightly lower. Treatment with 10% hAT-MSC-BM starting on Day 4 also improved the development rate and the total cell number of in vitro-fertilized embryos. This is the first report on the benefits of hAT-MSC-BM in a porcine embryo in vitro culture system. We conclude that hAT-MSC-BM is a new, alternative supplement that can improve the development of porcine embryos during both parthenogenesis and fertilization in vitro. © 2013 Wiley Periodicals, Inc.

  5. Bioactive molecules for biomimetic materials: Identification of RGD peptide sequences by TOF-S-SIMS analysis

    NASA Astrophysics Data System (ADS)

    Poulin, S.; Durrieu, M. C.; Polizu, S.; Yahia, L.'H.

    2006-07-01

    Implantable biomaterials, such as Ti-6Al-4V alloy, are designed to replace a part of the human body and/or its associated functions. This system, containing the alloy onto which the osteoprogenitor cells are deposited, is formed through the grafting of linear RGD (Arginine-Glycine-Aspartic acid) peptides. Our preliminary work demonstrated that the bonding of the fibronectin cell attachment peptide RGD to a metallic surface is extremely successful in promoting the adhesion and the proliferation of osteoprogenitor cells. However, a fuller understanding of the relationship between surface coverage and the contribution of each layer is required, in order to optimize the efficiency of the RGD-modified surface through optimal RGD bonding. We have used the TOF-S-SIMS analysis of this new surface, previously studied by XPS, to follow each modification level. Functional groups for peptide immobilization are required at the metallic surface, and their presence has been identified by mass spectra. A relative quantification of immobilized RGD peptides is obtained by TOF-S-SIMS analysis. Molecular ion imaging informs us of the surface evolution throughout the modification process and offers a description of each group. A comparative analysis of the spectra has permitted us to correlate the presence of these species on the surface with their bioactivities.

  6. Calcium silicate and calcium hydroxide materials for pulp capping: biointeractivity, porosity, solubility and bioactivity of current formulations.

    PubMed

    Gandolfi, Maria Giovanna; Siboni, Francesco; Botero, Tatiana; Bossù, Maurizio; Riccitiello, Francesco; Prati, Carlo

    2015-01-01

    The chemical-physical properties of novel and long-standing calcium silicate cements versus conventional pulp capping calcium hydroxide biomaterials were compared. Calcium hydroxide-based (Calxyl, Dycal, Life, Lime-Lite) and calcium silicate-based (ProRoot MTA, MTA Angelus, MTA Plus, Biodentine, Tech Biosealer capping, TheraCal) biomaterials were examined. Calcium and hydroxyl ion release, water sorption, interconnected open pores, apparent porosity, solubility and apatite-forming ability in simulated body fluid were evaluated. All calcium silicate materials released more calcium. Tech Biosealer capping, MTA Plus gel and Biodentine showed the highest values of calcium release, while Lime-Lite the lowest. All the materials showed alkalizing activity except for Life and Lime-Lite. Calcium silicate materials showed high porosity values: Tech Biosealer capping, MTA Plus gel and MTA Angelus showed the highest values of porosity, water sorption and solubility, while TheraCal the lowest. The solubility of water-containing materials was higher and correlated with the liquid-to-powder ratio. Calcium phosphate (CaP) deposits were noted on materials surfaces after short aging times. Scant deposits were detected on Lime-Lite. A CaP coating composed of spherulites was detected on all calcium silicate materials and Dycal after 28 days. The thickness, continuity and Ca/P ratio differed markedly among the materials. MTA Plus showed the thickest coating, ProRoot MTA showed large spherulitic deposits, while TheraCal presented very small dense spherulites. calcium silicate-based cements are biointeractive (ion-releasing) bioactive (apatite-forming) functional biomaterials. The high rate of calcium release and the fast formation of apatite may well explain the role of calcium silicate biomaterials as scaffold to induce new dentin bridge formation and clinical healing.

  7. Development of a bioactive implant for repair and potential healing of cranial defects.

    PubMed

    Engstrand, Thomas; Kihlström, Lars; Neovius, Erik; Skogh, Ann-Charlott Docherty; Lundgren, T Kalle; Jacobsson, Hans; Bohlin, Jan; Åberg, Jonas; Engqvist, Håkan

    2014-01-01

    The repair of complex craniofacial bone defects is challenging and a successful result is dependent on the size of the defect, quality of the soft tissue covering the defect, and choice of reconstruction method. The objective of this study was to develop a bioactive cranial implant that could provide a permanent reconstructive solution to the patient by stimulating bone healing of the defect. In this paper the authors report on the feasibility and clinical results of using such a newly developed device for the repair of a large traumatic and therapy-resistant cranial bone defect. The patient had undergone numerous attempts at repair, in which established methods had been tried without success. A mosaic-designed device was manufactured and implanted, comprising interconnected ceramic tiles with a defined calcium phosphate composition. The clinical outcome 30 months after surgery revealed a restored cranial vault without postoperative complications. Computed tomography demonstrated signs of bone ingrowth. Examination with combined (18)F-fluoride PET and CT provided further evidence of bone healing of the cranial defect.

  8. Bioactive phenols as potential neuroinflammation inhibitors from the leaves of Xanthoceras sorbifolia Bunge.

    PubMed

    Li, Ning; Wang, Ying; Li, Xuezheng; Zhang, Hong; Zhou, Di; Wang, Wenli; Li, Wei; Zhang, Xiangrong; Li, Xinyu; Hou, Yue; Meng, Dali

    2016-10-15

    Xanthoceras sorbifolia Bunge is a medicinal plant and also a valuable cash crop used for production of edible oil and biofuels in China. In our previous research, systematical phytochemical and bioactive profiles of different parts from X. sorbifolia have been obtained. Here we describe the effective phenols from the leaves of X. sorbifolia, which could function as natural neuroinflammation inhibitors. As a result, 23 compounds were characterized as the phenols from the leaves of X. sorbifolia by means of chromatographical methods and spectroscopic analysis. Among them, flavonoids quercetin3-O-β-d-glucopyarnoside (IC50 13.39±1.27μM), catechin (IC50 9.52±2.18μM), and phenylpropanoids syringaresinol-4-O-β-d-glucopyranoside (IC50 3.08±1.77μM), 4-O-β-d-glucopyranosyl-trans-p-coumaric acid (IC50 9.08±1.23μM) exhibited much stronger inhibiting effect on NO production than that of the positive control minocycline (IC50 37.04±2.09μM) in LPS-induced BV2 cells.

  9. Potential energy sputtering of EUVL materials

    SciTech Connect

    Pomeroy, J M; Ratliff, L P; Gillaspy, J D; Bajt, S

    2004-07-02

    Of the many candidates employed for understanding the erosion of critical Extreme Ultraviolet Lithography (EUVL) components, potential energy damage remains relatively uninvestigated. Unlike the familiar kinetic energy sputtering, which is a consequence of the momentum transferred by an ion to atoms in the target, potential energy sputtering occurs when an ion rapidly collects charge from the target as it neutralizes. Since the neutralization energy of a singly charged ion is typically on the order of 10 eV, potential energy effects are generally neglected for low charge state ions, and hence the bulk of the sputtering literature. As an ion's charge state is increased, the potential energy (PE) increases rapidly, e.g. PE(Xe{sup 1+})= 11 eV, PE(Xe{sup 10+}) = 810 eV, PE(Xe{sup 20+}) = 4.6 keV, etc. By comparison, the binding energy of a single atom on a surface is typically about 5 eV, so even relatively inefficient energy transfer mechanisms can lead to large quantities of material being removed, e.g. 25% efficiency for Xe{sup 10+} corresponds to {approx} 40 atoms/ion. By comparison, singly charged xenon ions with {approx} 20 keV of kinetic energy sputter only about 5 atoms/ion at normal incidence, and less than 1 atom/ion at typical EUV source energies. EUV light sources are optimized for producing approximately 10{sup 16} xenon ions per shot with an average charge state of q=10 in the core plasma. At operational rates of {approx}10 kHz, the number of ions produced per second becomes a whopping 10{sup 20}. Even if only one in a billion ions reaches the collector, erosion rates could reach {approx}10{sup 12} atoms per second, severely reducing the collector lifetime (for an average yield of 10 atoms/ion). In addition, efforts to reduce contamination effects may contribute to reduced neutralization and even larger potential energy damages rates (discussed further below). In order to provide accurate estimates for collector lifetimes and to develop mitigation schemes

  10. Enhanced bioactivity, biocompatibility and mechanical behavior of strontium substituted bioactive glasses.

    PubMed

    Arepalli, Sampath Kumar; Tripathi, Himanshu; Hira, Sumit Kumar; Manna, Partha Pratim; Pyare, Ram; S P Singh

    2016-12-01

    Strontium contained biomaterials have been reported as a potential bioactive material for bone regeneration, as it reduces bone resorption and stimulates bone formation. In the present investigation, the bioactive glasses were designed to partially substitute SrO for SiO2 in Na2O-CaO-SrO-P2O5-SiO2 system. This work demonstrates that the substitution of SrO for SiO2 has got significant benefit than substitution for CaO in the bioactive glass. Bioactivity was assessed by the immersion of the samples in simulated body fluid for different intervals. The formation of hydroxy carbonate apatite layer was identified by X-ray diffractometry, scanning electron microscopy (SEM) and energy dispersive spectroscopy. The elastic modulus of the bioactive glasses was measured and found to increase with increasing SrO for SiO2. The blood compatibility of the samples was evaluated. In vitro cell culture studies of the samples were performed using human osteosarcoma U2-OS cell lines and found a significant improvement in cell viability and proliferation. The investigation showed enhancement in bioactivity, mechanical and biological properties of the strontia substituted for silica in glasses. Thus, these bioactive glasses would be highly potential for bone regeneration. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Bioactive β-carbolines norharman and harman in traditional and novel raw materials for chicory coffee.

    PubMed

    Wojtowicz, Elżbieta; Zawirska-Wojtasiak, Renata; Przygoński, Krzysztof; Mildner-Szkudlarz, Sylwia

    2015-05-15

    The β-carboline compounds norharman and harman exhibit neuroactive activity in the human body. Chicory coffee has proved to be a source of β-carboline compounds. This study assessed the norharman and harman contents of traditional and novel raw materials for the production of chicory coffee, as well as in samples of chicory coffee with novel additives. The highest content of the β-carbolines among the traditional raw materials was recorded in roasted sugar beet (2.26 μg/g), while roasting the chicory caused a 25-fold increase in the content of norharman in this raw material (from 0.05 to 1.25 μg/g). In novel raw materials not subjected to the action of high temperature, β-carboline was not detected. Among the roasted novel raw materials, the highest contents of harman and norharman were found in artichokes. High harman levels were also recorded in roasted chokeberry.

  12. MARGINAL ADAPTATION AND PERFORMANCE OF BIOACTIVE DENTAL RESTORATIVE MATERIALS IN DECIDUOUS AND YOUNG PERMANENT TEETH

    PubMed Central

    Gjorgievska, Elizabeta; Nicholson, John W.; Iljovska, Snezana; Slipper, Ian J.

    2008-01-01

    Objective: The aim of this study was to investigate the adaptation of different types of restorations towards deciduous and young permanent teeth. Materials and Methods: Class V cavities were prepared in deciduous and young permanent teeth and filled with different materials (a conventional glass-ionomer, a resin-modified glass-ionomer, a poly-acid-modified composite resin and a conventional composite resin). Specimens were aged in artificial saliva for 1, 6, 12 and 18 months, then examined by SEM. Results: The composite resin and the polyacid-modified composite had better marginal adaptation than the glass-ionomers, though microcracks developed in the enamel of the tooth. The glass-ionomers showed inferior marginal quality and durability, but no microcracking of the enamel. The margins of the resin-modified glass-ionomer were slightly superior to the conventional glass-ionomer. Conditioning improved the adaptation of the composite resin, but the type of tooth made little or no difference to the performance of the restorative material. All materials were associated with the formation of crystals in the gaps between the filling and the tooth; the quantity and shape of these crystals varied with the material. Conclusions: Resin-based materials are generally better at forming sound, durable margins in deciduous and young permanent teeth than cements, but are associated with microcracks in the enamel. All fluoride-releasing materials give rise to crystalline deposits. PMID:19089281

  13. HepG2 cells simultaneously expressing five P450 enzymes for the screening of hepatotoxicity: identification of bioactivable drugs and the potential mechanism of toxicity involved.

    PubMed

    Tolosa, Laia; Gómez-Lechón, M José; Pérez-Cataldo, Gabriela; Castell, José V; Donato, M Teresa

    2013-06-01

    Use of the HepG2 cell line to assess hepatotoxicity induced by bioactivable compounds is hampered by their low cytochrome P450 expression. To overcome this limitation, we have used adenoviral transfection to develop upgraded HepG2 cells (ADV-HepG2) expressing the major P450 enzymes involved in drug metabolism (CYP1A2, CYP2D6, CYP2C9, CYP2C19, and CYP3A4) at levels comparable to those of human hepatocytes. The potential utility of this new cell model for the in vitro screening of bioactivable drugs was assessed using a high-content screening assay that we recently developed to simultaneously measure multiple parameters indicative of cell injury. To this end, ADV-HepG2 and HepG2 cells, cultured in 96-well plates, were exposed for 24 h to a wide range of concentrations of 12 bioactivable and 3 non-bioactivable compounds. The cell viability and parameters associated with nuclear morphology, mitochondrial function, intracellular calcium concentration, and oxidative stress indicative of prelethal cytotoxicity and representative of different mechanisms of toxicity were evaluated. Bioactivable compounds showed lower IC(50) values in ADV-HepG2 cells than in HepG2 cells. Moreover, significant differences in the other parameters analyzed were observed between both cell models, while similar effects were observed for non-bioactivable compounds (negative controls). The changes in cell parameters detected in our assay for a given compound are in good agreement with the previously reported toxicity mechanism. Overall, our results indicate that this assay may be a suitable new in vitro approach for early screening of compounds to identify bioactivable hepatotoxins and the mechanism(s) involved in their toxicity.

  14. The Quest for a Simple Bioactive Analog of Paclitaxel as a Potential Anticancer Agent

    PubMed Central

    2015-01-01

    Conspectus Paclitaxel (PTX), introduced into the clinic in 1991, has revealed itself as an effective antimicrotubule drug for treatment of a range of otherwise intractable cancers. Along with docetaxel (DTX) and in combination with other agents such as cisplatin, it has proven to be a first-line therapy. Unfortunately, PTX and DTX carry severe liabilities such as debilitating side effects, rapid onset of resistance, and rather complex molecular structures offering substantial challenges to ease of synthetic manipulation. Consequently, the past 15 years has witnessed many efforts to synthesize and test highly modified analogs based on intuitive structural similarity relationships with the PTX molecular skeleton, as well as efforts to mimic the conformational profile of the ligand observed in the macromolecular tubulin–PTX complex. Highly successful improvements in potency, up to 50-fold increases in IC50, have been achieved by constructing bridges between distal centers in PTX that imitate the conformer of the electron crystallographic binding pose. Much less successful have been numerous attempts to truncate PTX by replacing the baccatin core with simpler moieties to achieve PTX-like potencies and applying a wide range of flexible synthesis-based chemistries. Reported efforts, characterized by a fascinating array of baccatin substitutes, have failed to surpass the bioactivities of PTX in both microtubule disassembly assays and cytotoxicity measurements against a range of cell types. Most of the structures retain the main elements of the PTX C13 side chain, while seeking a smaller rigid bicycle as a baccatin replacement adorned with substituents to mimic the C2 benzoyl moiety and the oxetane ring. We surmise that past studies have been handicapped by solubility and membrane permeability issues, but primarily by the existence of an expansive taxane binding pocket and the discrepancy in molecular size between PTX and the pruned analogs. A number of these molecules

  15. Exploring Bioactive Properties of Marine Cyanobacteria Isolated from the Portuguese Coast: High Potential as a Source of Anticancer Compounds

    PubMed Central

    Costa, Margarida; Garcia, Mónica; Costa-Rodrigues, João; Costa, Maria Sofia; Ribeiro, Maria João; Fernandes, Maria Helena; Barros, Piedade; Barreiro, Aldo; Vasconcelos, Vitor; Martins, Rosário

    2013-01-01

    The oceans remain a major source of natural compounds with potential in pharmacology. In particular, during the last few decades, marine cyanobacteria have been in focus as producers of interesting bioactive compounds, especially for the treatment of cancer. In this study, the anticancer potential of extracts from twenty eight marine cyanobacteria strains, belonging to the underexplored picoplanktonic genera, Cyanobium, Synechocystis and Synechococcus, and the filamentous genera, Nodosilinea, Leptolyngbya, Pseudanabaena and Romeria, were assessed in eight human tumor cell lines. First, a crude extract was obtained by dichloromethane:methanol extraction, and from it, three fractions were separated in a Si column chromatography. The crude extract and fractions were tested in eight human cancer cell lines for cell viability/toxicity, accessed with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and lactic dehydrogenase release (LDH) assays. Eight point nine percent of the strains revealed strong cytotoxicity; 17.8% showed moderate cytotoxicity, and 14.3% assays showed low toxicity. The results obtained revealed that the studied genera of marine cyanobacteria are a promising source of novel compounds with potential anticancer activity and highlight the interest in also exploring the smaller filamentous and picoplanktonic genera of cyanobacteria. PMID:24384871

  16. Screening for Potential Bioactive Components in Ginkgo biloba Extract by the Rat Renal Tubular Epithelial Cell Extraction and LC-MS/MS.

    PubMed

    Li, Ying; Li, Yin-jie; Li, Zheng; Qiu, Jing-Ying; Zheng, Xiao-Xiao; Bian, Ting-Ting; Gao, Feng-Lei; Yu, Yan-Yan; Yang, Dong-Zhi; Tang, Dao-Quan

    2015-01-01

    Rat renal tubular epithelial cell (RTEC) cultured with high glucose has been used to observe the protective effect of Ginkgo biloba extract (GBE) against diabetic nephropathy (DN). The compounds in GBE binding with cell membrane or entering into cell are still unknown, which may be potential bioactive components. In this paper, a powerful method for screening and analyzing the potential bioactive components from GBE was developed using cell extraction coupled with high performance liquid chromatography tandem mass spectrometry (LC-MS/MS). 8 prototype compounds and 5 metabolites were obtained, among which 6 prototype compounds and 1 metabolite were identified or tentatively characterized as rutin, bilobalide, ginkgolide B, ginkgolide C, genkwanin, apigenin and diosmetin by comparing their retention times and MS spectra with those of authentic standards or literature data. The 6 prototype compounds were further quantitatively analyzed using electrospray ionization in negative mode multiple reaction monitoring (MRM). The results showed that high glucose changed the Tmax, MRT(0-t), Cmax and AUC(0-t) of all observed compounds and decreased the t1/2 of genkwanin and apigenin, significantly. The overall findings indicate that 8 prototype compounds may be the potential bioactive components of GBE with preventive effect against DN and the method of RTEC extraction coupled with LC-MS/MS technology screening method we developed is a feasible, rapid, and useful tool for screening and analyzing potential bioactive components.

  17. The potential of encapsulating "raw materials" in 3D osteochondral gradient scaffolds.

    PubMed

    Mohan, Neethu; Gupta, Vineet; Sridharan, Banupriya; Sutherland, Amanda; Detamore, Michael S

    2014-04-01

    Scaffolds with continuous gradients in material composition and bioactive signals enable a smooth transition of properties at the interface. Components like chondroitin sulfate (CS) and bioactive glass (BG) in 3D scaffolds may serve as "raw materials" for synthesis of new extracellular matrix (ECM), and may have the potential to completely or partially replace expensive growth factors. We hypothesized that scaffolds with gradients of ECM components would enable superior performance of engineered constructs. Raw material encapsulation altered the appearance, structure, porosity, and degradation of the scaffolds. They allowed the scaffolds to better retain their 3D structure during culture and provided a buffering effect to the cells in culture. Following seeding of rat mesenchymal stem cells, there were several instances where glycosaminoglycan (GAG), collagen, or calcium contents were higher with the scaffolds containing raw materials (CS or BG) than with those containing transforming growth factor (TGF)-β3 or bone morphogenetic protein (BMP)-2. It was also noteworthy that a combination of both CS and TGF-β3 increased the secretion of collagen type II. Moreover, cells seeded in scaffolds containing opposing gradients of CS/TGF-β3 and BG/BMP-2 produced clear regional variations in the secretion of tissue-specific ECM. The study demonstrated raw materials have the potential to create a favorable microenvironment for cells; they can significantly enhance the synthesis of certain extracellular matrix (ECM) components when compared to expensive growth factors; either alone or in combination with growth factors they can enhance the secretion of tissue specific matrix proteins. Raw materials are promising candidates that can be used to either replace or be used in combination with growth factors. Success with raw materials in lieu of growth factors could have profound implications in terms of lower cost and faster regulatory approval for more rapid translation of

  18. Biomolecule immobilization techniques for bioactive paper fabrication.

    PubMed

    Kong, Fanzhi; Hu, Yim Fun

    2012-04-01

    Research into paper-based sensors or functional materials that can perform analytical functions with active recognition capabilities is rapidly expanding, and significant research effort has been made into the design and fabrication of bioactive paper at the biosensor level to detect potential health hazards. A key step in the fabrication of bioactive paper is the design of the experimental and operational procedures for the immobilization of biomolecules such as antibodies, enzymes, phages, cells, proteins, synthetic polymers and DNA aptamers on a suitably prepared paper membrane. The immobilization methods are concisely categorized into physical absorption, bioactive ink entrapment, bioaffinity attachment and covalent chemical bonding immobilization. Each method has individual immobilization characteristics. Although every biomolecule-paper combination has to be optimized before use, the bioactive ink entrapment method is the most commonly used approach owing to its general applicability and biocompatibility. Currently, there are four common applications of bioactive paper: (1) paper-based bioassay or paper-based analytical devices for sample conditioning; (2) counterfeiting and countertempering in the packaging and construction industries; (3) pathogen detection for food and water quality monitoring; and (4) deactivation of pathogenic bacteria using antimicrobial paper. This article reviews and compares the different biomolecule immobilization techniques and discusses current trends. Current, emerging and future applications of bioactive paper are also discussed.

  19. Structural, spectroscopic and molecular docking studies on 2-amino-3-chloro-5-trifluoromethyl pyridine: A potential bioactive agent.

    PubMed

    Mohamed Asath, R; Premkumar, R; Mathavan, T; Milton Franklin Benial, A

    2017-03-15

    The most stable, optimized structure of the 2-amino-3-chloro-5-trifluoromethyl pyridine (ACTP) molecule was predicted by the density functional theory calculations using the B3LYP method with cc-pVQZ basis set. Antitumor activity of the ACTP molecule was evaluated by molecular docking analysis. The structural parameters and vibrational wavenumbers were calculated for the optimized molecular structure. The experimental and theoretical vibrational wavenumbers were assigned and compared. Ultraviolet-visible spectrum was simulated and validated experimentally. The molecular electrostatic potential surface was simulated. Frontier molecular orbitals and related molecular properties were computed and further density of states spectrum was simulated. The natural bond orbital analysis was also performed to confirm the bioactivity of the ACTP molecule. The molecular docking analysis reveals the better inhibitory nature of the ACTP molecule against the colony-stimulating factor 1 (CSF1) gene which causes tenosynovial giant-cell tumor. Hence, the ACTP molecule can act as a potential inhibitor against tenosynovial giant-cell tumor.

  20. Structural, spectroscopic and molecular docking studies on 2-amino-3-chloro-5-trifluoromethyl pyridine: A potential bioactive agent

    NASA Astrophysics Data System (ADS)

    Mohamed Asath, R.; Premkumar, R.; Mathavan, T.; Milton Franklin Benial, A.

    2017-03-01

    The most stable, optimized structure of the 2-amino-3-chloro-5-trifluoromethyl pyridine (ACTP) molecule was predicted by the density functional theory calculations using the B3LYP method with cc-pVQZ basis set. Antitumor activity of the ACTP molecule was evaluated by molecular docking analysis. The structural parameters and vibrational wavenumbers were calculated for the optimized molecular structure. The experimental and theoretical vibrational wavenumbers were assigned and compared. Ultraviolet-visible spectrum was simulated and validated experimentally. The molecular electrostatic potential surface was simulated. Frontier molecular orbitals and related molecular properties were computed and further density of states spectrum was simulated. The natural bond orbital analysis was also performed to confirm the bioactivity of the ACTP molecule. The molecular docking analysis reveals the better inhibitory nature of the ACTP molecule against the colony-stimulating factor 1 (CSF1) gene which causes tenosynovial giant-cell tumor. Hence, the ACTP molecule can act as a potential inhibitor against tenosynovial giant-cell tumor.

  1. Methods for the Evaluation of the Bioactivity and Biocontrol Potential of Species of Trichoderma.

    PubMed

    Steyaert, Johanna; Hicks, Emily; Kandula, Janaki; Kandula, Diwakar; Alizadeh, Hossein; Braithwaite, Mark; Yardley, Jessica; Mendoza-Mendoza, Artemio

    2016-01-01

    Members of the genus Trichoderma comprise the majority of commercial fungal biocontrol agents of plant diseases. As such, there is a wealth of information available on the analysis of their biocontrol potential and the mechanisms behind their superior abilities. This chapter aims to summarize the most common methods utilized within a Trichoderma biocontrol program for assessing the biological properties of individual strains.

  2. Porous Silicon-Based Cell Microarrays: Optimizing Human Endothelial Cell-Material Surface Interactions and Bioactive Release.

    PubMed

    Dalilottojari, Adel; Delalat, Bahman; Harding, Frances J; Cockshell, Michaelia P; Bonder, Claudine S; Voelcker, Nicolas H

    2016-11-14

    Porous silicon (pSi) substrates are a promising platform for cell expansion, since pore size and chemistry can be tuned to control cell behavior. In addition, a variety of bioactives can be loaded into the pores and subsequently released to act on cells adherent to the substrate. Here, we construct a cell microarray on a plasma polymer coated pSi substrate that enables the simultaneous culture of human endothelial cells on printed immobilized protein factors, while a second soluble growth factor is released from the same substrate. This allows three elements of candidate pSi scaffold materials-topography, surface functionalization, and controlled factor release-to be assessed simultaneously in high throughput. We show that protein conjugation within printed microarray spots is more uniform on the pSi substrate than on flat glass or silicon surfaces. Active growth factors are released from the pSi surface over a period of several days. Using an endothelial progenitor cell line, we investigate changes in cell behavior in response to the microenvironment. This platform facilitates the design of advanced functional biomaterials, including scaffolds, and carriers for regenerative medicine and cell therapy.

  3. Pulsed laser ablation and deposition of bioactive glass as coating material for biomedical applications

    NASA Astrophysics Data System (ADS)

    D'Alessio, L.; Teghil, R.; Zaccagnino, M.; Zaccardo, I.; Ferro, D.; Marotta, V.

    1999-01-01

    A study of the laser ablation and deposition, on Ti-Al substrates, of a biologically active glass (Bioglass®) suitable for bone implants is reported. The analysis of the gaseous phase by emission spectroscopy and the characterisation of the films from a compositional and morphological point of view have been carried out. The mean chemical composition of the deposits obtained from Bioglass ablation is very close to the target composition and the morphology indicates that different mechanisms of material ejection are present.

  4. Gallic acid grafting modulates the oxidative potential of ferrimagnetic bioactive glass-ceramic SC-45.

    PubMed

    Corazzari, Ingrid; Tomatis, Maura; Turci, Francesco; Ferraris, Sara; Bertone, Elisa; Prenesti, Enrico; Vernè, Enrica

    2016-12-01

    Magnetite-containing glass-ceramics are promising bio-materials for replacing bone tissue after tumour resection. Thanks to their ferrimagnetic properties, they generate heat when subjected to an alternated magnetic field. In virtue of this they can be employed for the hyperthermic treatment of cancer. Moreover, grafting anti-cancer drugs onto their surface produces specific anti-neoplastic activity in these biomaterials. Gallic acid (GA) exhibits antiproliferative activity which renders it a promising candidate for anticancer applications. In the present paper, the reactivity of ferrimagnetic glass-ceramic SC-45 grafted with GA (SC-45+GA) was studied in terms of ROS release, rupture of the C-H bond of the formate molecule and Fenton reactivity by EPR/spin trapping in acellular systems. The ability of these materials to cause lipid peroxidation was assessed by UV-vis/TBA assay employing linoleic acid as a model of membrane lipid. The results, compared to those obtained with SC-45, showed that GA grafting (i) significantly enhanced the Fenton reactivity and (ii) restored the former reactivity of SC-45 towards both the C-H bond and linoleic acid which had been completely suppressed by prolonged contact with water. Fe(2+) centres at the surface are probably implicated. GA, acting as a pro-oxidant, reduces Fe(3+) to Fe(2+) by maintaining a supply of Fe(2+) at the surface of SC-45+GA.

  5. Naturally derived micelles for rapid in vitro screening of potential cholesterol-lowering bioactives.

    PubMed

    Kirana, Chandra; Rogers, Paul F; Bennett, Louise E; Abeywardena, Mahinda Y; Patten, Glen S

    2005-06-01

    A high plasma cholesterol level, especially low-density lipoprotein cholesterol, indicates increased risk of cardiovascular diseases. Plasma cholesterol levels are influenced by diet and cholesterol biosynthesis, uptake, and secretion. Cholesterol uptake involves solubilization into complex phospholipid spherical bodies termed micelles that facilitate the transport of lipids through the gut brush border membrane into enterocytes. In vitro assays reported to date to determine potential cholesterol-lowering effects of various compounds require artificial micelle preparations that are elaborate and time-consuming to prepare. The aims of this study were to compare the efficacy of artificially prepared micelles with naturally derived micelles from pig's bile and to test their ability to assess potential inhibitors of cholesterol uptake. The suitability of pig's bile-derived micelles was tested both at the level of the micelle and at cellular uptake using cultured Caco-2 cells. Known cholesterol uptake inhibitors at the micelle (green tea catechins) and at the Caco-2 cell (beta-lactoglobulin-derived peptide, IIAEK) were used as reference inhibitory compounds. It was concluded that pig's bile was a rapid, reproducible, convenient, and cost-effective source of micelles for cholesterol micelle solubility and cellular uptake assay systems and is suitable for screening purposes focused on identifying potential cholesterol-lowering agents.

  6. Improving In Vivo Efficacy of Bioactive Molecules: An Overview of Potentially Antitumor Phytochemicals and Currently Available Lipid-Based Delivery Systems

    PubMed Central

    Torres, Carlos; Vázquez, Luis; Reglero, Guillermo; Fornari, Tiziana

    2017-01-01

    Cancer is among the leading causes of morbidity and mortality worldwide. Many of the chemotherapeutic agents used in cancer treatment exhibit cell toxicity and display teratogenic effect on nontumor cells. Therefore, the search for alternative compounds which are effective against tumor cells but reduce toxicity against nontumor ones is of great importance in the progress or development of cancer treatments. In this sense, scientific knowledge about relevant aspects of nutrition intimately involved in the development and progression of cancer progresses rapidly. Phytochemicals, considered as bioactive ingredients present in plant products, have shown promising effects as potential therapeutic/preventive agents on cancer in several in vitro and in vivo assays. However, despite their bioactive properties, phytochemicals are still not commonly used in clinical practice due to several reasons, mainly attributed to their poor bioavailability. In this sense, new formulation strategies are proposed as carriers to improve their bioefficacy, highlighting the use of lipid-based delivery systems. Here, we review the potential antitumoral activity of the bioactive compounds derived from plants and the current studies carried out in animal and human models. Furthermore, their association with lipids as a formulation strategy to enhance their efficacy in vivo is also reported. The development of high effective bioactive supplements for cancer treatment based on the improvement of their bioavailability goes through this association. PMID:28555156

  7. Fixation of bioactive calcium alkali phosphate on Ti6Al4V implant material with femtosecond laser pulses

    NASA Astrophysics Data System (ADS)

    Symietz, Christian; Lehmann, Erhard; Gildenhaar, Renate; Koter, Robert; Berger, Georg; Krüger, Jörg

    2011-04-01

    Bone implants made of metal, often titanium or the titanium alloy Ti6Al4V, need to be surface treated to become bioactive. This enables the formation of a firm and durable connection of the prosthesis with the living bone. We present a new method to uniformly cover Ti6Al4V with a thin layer of ceramics that imitates bone material. These calcium alkali phosphates, called GB14 and Ca10, are applied to the metal by dip coating of metal plates into an aqueous slurry containing the fine ceramic powder. The dried samples are illuminated with the 790 nm radiation of a pulsed femtosecond laser. If the laser fluence is set to a value just below the ablation threshold of the ceramic (ca. 0.4 J/cm 2) the 30 fs laser pulses penetrate the partly transparent ceramic layer of 20-40 μm thickness. The remaining laser fluence at the ceramic-metal interface is still high enough to generate a thin metal melt layer leading to the ceramic fixation on the metal. The laser processing step is only possible because Ti6Al4V has a lower ablation threshold (between 0.1 and 0.15 J/cm 2) than the ceramic material. After laser treatment in a fluence range between 0.1 and 0.4 J/cm 2, only the particles in contact with the metal withstand a post-laser treatment (ultrasonic cleaning). The non-irradiated rest of the layer is washed off. In this work, we present results of a successful ceramic fixation extending over larger areas. This is fundamental for future applications of arbitrarily shaped implants.

  8. Enzyme-Assisted Extraction of Bioactive Material from Chondrus crispus and Codium fragile and Its Effect on Herpes simplex Virus (HSV-1)

    PubMed Central

    Kulshreshtha, Garima; Burlot, Anne-Sophie; Marty, Christel; Critchley, Alan; Hafting, Jeff; Bedoux, Gilles; Bourgougnon, Nathalie; Prithiviraj, Balakrishnan

    2015-01-01

    Codium fragile and Chondrus crispus are, respectively, green and red seaweeds which are abundant along the North Atlantic coasts. We investigated the chemical composition and antiviral activity of enzymatic extracts of C. fragile (CF) and C. crispus (CC). On a dry weight basis, CF consisted of 11% protein, 31% neutral sugars, 0.8% sulfate, 0.6% uronic acids, and 49% ash, while CC contained 27% protein, 28% neutral sugars, 17% sulfate, 1.8% uronic acids, and 25% ash. Enzyme-assisted hydrolysis improved the extraction efficiency of bioactive materials. Commercial proteases and carbohydrases significantly improved (p ≤ 0.001) biomass yield (40%–70% dry matter) as compared to aqueous extraction (20%–25% dry matter). Moreover, enzymatic hydrolysis enhanced the recovery of protein, neutral sugars, uronic acids, and sulfates. The enzymatic hydrolysates exhibited significant activity against Herpes simplex virus (HSV-1) with EC50 of 77.6–126.8 μg/mL for CC and 36.5–41.3 μg/mL for CF, at a multiplicity of infection (MOI) of 0.001 ID50/cells without cytotoxity (1–200 μg/mL). The extracts obtained from proteases (P1) and carbohydrases (C3) were also effective at higher virus MOI of 0.01 ID50/cells without cytotoxity. Taken together, these results indicate the potential application of enzymatic hydrolysates of C. fragile and C. crispus in functional food and antiviral drug discovery. PMID:25603348

  9. Recovery potential of cold press byproducts obtained from the edible oil industry: physicochemical, bioactive, and antimicrobial properties.

    PubMed

    Karaman, Safa; Karasu, Salih; Tornuk, Fatih; Toker, Omer Said; Geçgel, Ümit; Sagdic, Osman; Ozcan, Nihat; Gül, Osman

    2015-03-04

    Physicochemical, bioactive, and antimicrobial properties of different cold press edible oil byproducts (almond (AOB), walnut (WOB), pomegranate (POB), and grape (GOB)) were investigated. Oil, protein, and crude fiber content of the byproducts were found between 4.82 and 12.57%, between 9.38 and 49.05%, and between 5.87 and 45.83%, respectively. GOB had very high crude fiber content; therefore, it may have potential for use as a new dietary fiber source in the food industry. As GOB, POB, and WOB oils were rich in polyunsaturated fatty acids, AOB was rich in monounsaturated fatty acids. Oil byproducts were also found to be rich in dietary mineral contents, especially potassium, calcium, phosphorus, and magnesium. WOB had highest total phenolic (802 ppm), flavonoid (216 ppm), and total hydrolyzed tannin (2185 ppm) contents among the other byproducts. Volatile compounds of all the byproducts are mainly composed of terpenes in concentration of approximately 95%. Limonene was the dominant volatile compound in all of the byproducts. Almond and pomegranate byproduct extracts showed antibacterial activity depending on their concentration, whereas those of walnut and grape byproducts showed no antibacterial activity against any pathogenic bacteria tested. According to the results of the present study, walnut, almond, pomegranate, and grape seed oil byproducts possess valuable properties that can be taken into consideration for improvement of nutritional and functional properties of many food products.

  10. Remineralization potential of bioactive glass and casein phosphopeptide-amorphous calcium phosphate on initial carious lesion: An in-vitro pH-cycling study

    PubMed Central

    Mehta, Adit Bharat; Kumari, Veena; Jose, Rani; Izadikhah, Vajiheh

    2014-01-01

    Aims: The aim of this study was to evaluate and compare the remineralization potential of bioactive-Glass (BAG) (Novamin®/Calcium-sodium-phosphosilicate) and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) containing dentifrice. Materials and Methods: A total of 30 sound human premolars were decoronated, coated with nail varnish except for a 4 mm × 4 mm window on the buccal surface of crown and were randomly divided in two groups (n = 15). Group A — BAG dentifrice and Group B — CPP-ACP dentifrice. The baseline surface microhardness (SMH) was measured for all the specimens using the vickers microhardness testing machine. Artificial enamel carious lesions were created by inserting the specimens in de-mineralizing solution for 96 h. SMH of demineralized specimens was evaluated. 10 days of pH-cycling regimen was carried out. SMH of remineralized specimens was evaluated. Statistical Analysis: Data was analyzed using ANOVA and multiple comparisons within groups was done using Bonferroni method (post-hoc tests) to detect significant differences at P < 0.05 levels. Results: Group A showed significantly higher values (P < 0.05) when compared with the hardness values of Group B. Conclusions: Within the limits; the present study concluded that; both BAG and CPP-ACP are effective in remineralizing early enamel caries. Application of BAG more effectively remineralized the carious lesion when compared with CPP-ACP. PMID:24554851

  11. Phytochemistry, Bioactivity and Potential Impact on Health of Juglans: the Original Plant of Walnut.

    PubMed

    Bi, Dongdong; Zhao, Yicheng; Jiang, Rui; Wang, Yan; Tian, Yuxin; Chen, Xiaoyi; Bai, Shaojuan; She, Gaimei

    2016-06-01

    Walnuts are seeds with a hard shell from the genus Juglans (J. mandshurica, J. regia, J. sinensis, J. cathayensis, J. nigra and J. sigillata). Walnuts can nourish brain cells to improve human memory. Other parts of the plant are also employed as traditional Chinese medicines. Modern research on Juglans species has been mostly focused on the above-mentioned species, the seeds of which are all called walnuts. Juglans species have diverse chemical constituents, including diarylheptanoids, quinones, polyphenols, flavones and terpenes. The diarylheptanoids and quinones have notable antitumor activity, supplying new lead compounds for preparing antitumor drugs. The potent pain-relieving, antioxidant, antibacterial and antitumor activities of these plants are significant. In the review, comprehensive information on the nutritional characteristics, traditional functions, chemical constituents, and biological activities of the Juglans species, together with the seeds used as walnuts is provided to explore their potential and to advance research.

  12. Osthole: A Review on Its Bioactivities, Pharmacological Properties, and Potential as Alternative Medicine

    PubMed Central

    Zhang, Zhong-Rong; Leung, Wing Nang; Cheung, Ho Yee; Chan, Chun Wai

    2015-01-01

    This paper reviews the latest understanding of biological and pharmacological properties of osthole (7-methoxy-8-(3-methyl-2-butenyl)-2H-1-benzopyran-2-one), a natural product found in several medicinal plants such as Cnidium monnieri and Angelica pubescens. In vitro and in vivo experimental results have revealed that osthole demonstrates multiple pharmacological actions including neuroprotective, osteogenic, immunomodulatory, anticancer, hepatoprotective, cardiovascular protective, and antimicrobial activities. In addition, pharmacokinetic studies showed osthole uptake and utilization are fast and efficient in body. Moreover, the mechanisms of multiple pharmacological activities of osthole are very likely related to the modulatory effect on cyclic adenosine monophosphate (cAMP) and cyclic adenosine monophosphate (cGMP) level, though some mechanisms remain unclear. This review aims to summarize the pharmacological properties of osthole and give an overview of the underlying mechanisms, which showcase its potential as a multitarget alternative medicine. PMID:26246843

  13. Development of prototypes of bioactive packaging materials based on immobilized bacteriophages for control of growth of bacterial pathogens in foods.

    PubMed

    Lone, Ayesha; Anany, Hany; Hakeem, Mohammed; Aguis, Louise; Avdjian, Anne-Claire; Bouget, Marina; Atashi, Arash; Brovko, Luba; Rochefort, Dominic; Griffiths, Mansel W

    2016-01-18

    significantly reduce the growth of L. monocytogenes at both storage temperatures, 4°C and 10°C, for 25 days regardless of bacteriophage application format (immobilized or non-immobilized (free)). In conclusion, the developed phage-based materials demonstrated significant antimicrobial effect, when applied to the artificially contaminated foods, and can be used as prototypes for developing bioactive antimicrobial packaging materials capable of enhancing the safety of fresh produce and RTE meat. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Fabrication and characterization of strontium incorporated 3-D bioactive glass scaffolds for bone tissue from biosilica.

    PubMed

    Özarslan, Ali Can; Yücel, Sevil

    2016-11-01

    Bioactive glass scaffolds that contain silica are high viable biomaterials as bone supporters for bone tissue engineering due to their bioactive behaviour in simulated body fluid (SBF). In the human body, these materials help inorganic bone structure formation due to a combination of the particular ratio of elements such as silicon (Si), calcium (Ca), sodium (Na) and phosphorus (P), and the doping of strontium (Sr) into the scaffold structure increases their bioactive behaviour. In this study, bioactive glass scaffolds were produced by using rice hull ash (RHA) silica and commercial silica based bioactive glasses. The structural properties of scaffolds such as pore size, porosity and also the bioactive behaviour were investigated. The results showed that undoped and Sr-doped RHA silica-based bioactive glass scaffolds have better bioactivity than that of commercial silica based bioactive glass scaffolds. Moreover, undoped and Sr-doped RHA silica-based bioactive glass scaffolds will be able to be used instead of undoped and Sr-doped commercial silica based bioactive glass scaffolds for bone regeneration applications. Scaffolds that are produced from undoped or Sr-doped RHA silica have high potential to form new bone for bone defects in tissue engineering. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Biofabricated marine hydrozoan: a bioactive crystalline material promoting ossification of mesenchymal stem cells.

    PubMed

    Abramovitch-Gottlib, Liat; Geresh, Shimona; Vago, Razi

    2006-04-01

    This study introduces a novel three-dimensional biomatrix obtained from the marine hydrocoral Millepora dichotoma as a scaffold for hard tissue engineering. Millepora dichotoma was biofabricated under field and laboratory conditions. Three-dimensional biomatrices were made in order to convert mesenchymal stem cells (MSCs) to exemplify osteoblastic phenotype. We investigated the effect of the biomatrices on MSCs proliferation and differentiation at 2, 3, 4, 7, 10, 14, 21, 28, and 42 days. Different analyses were made: light microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), calcium incorporation to newly formed tissue (alizarin red), bone nodule formation (von Kossa), fat aggregate formation (oil red O), collagen type I immunofluorescence, DNA concentrations, alkaline phosphatase (ALP) activity, and osteocalcin concentrations. MSCs seeded on Millepora dichotoma biomatrices showed higher levels of calcium and phosphate incorporation and higher type I collagen levels than did control Porites lutea biomatrices. ALP activity revealed that MSCs seeded on M. dichotoma biomatrices are highly osteogenic compared to those on control biomatrices. The osteocalcin content of MSCs seeded on M. dichotoma remained constant up to 2 weeks before rising to surpass that of seeded P. lutea biomatrices after 28 days. Our study thus showed that M. dichotoma biomatrices enhance the differentiation of MSCs into osteoblast and hence have excellent potential as bioscaffold for hard tissue engineering.

  16. One-pot nanoparticulation of potentially bioactive peptides and gallic acid encapsulation.

    PubMed

    Nourbakhsh, Himan; Madadlou, Ashkan; Emam-Djomeh, Zahra; Wang, Yi-Cheng; Gunasekaran, Sundaram

    2016-11-01

    Whey protein isolate was hydrolyzed to an in vitro antioxidative hydrolysate, followed by transglutaminase-induced cross-linking and microemulsification in an oil phase. The obtained microemulsion was then dispersed in a gallic acid-rich model wastewater which caused gallic acid transportation into internal nanodroplets. Whey peptides were consequently gelled, yielding nanoparticles. Electrophoresis showed that β-lactoglobulin and low molecular weight peptides were cross-linked by transglutaminase. Protein hydrolysis and subsequent enzymatic cross-linking increased the ζ-potential value. Microscopic investigation indicated that most particles were non-spherical. Non-cross-linked and cross-linked peptides underwent a form of heat-triggered self-assembly in the dry state, while nanoparticles did not show such behavior. Peptide crystallites size was increased by cross-linking and acid-induced particle formation. The latter also caused a reduction in intensity of C-H stretching and C-N bending peaks in infra-red spectrum. Gallic acid release from particles to simulated gastrointestinal fluids was through diffusion from swollen particles, and reached almost 70% release. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Bioactive lipids, radical scavenging potential, and antimicrobial properties of cold pressed clove (Syzygium aromaticum) oil.

    PubMed

    Assiri, Adel Mohamad Ali; Hassanien, Mohamed F R

    2013-11-01

    Health promoting cold pressed oils may improve human health and prevent certain diseases. It is hard to find any research concerning the composition and functional properties of cold pressed clove (Syzygium aromaticum) oil (CO). Cold pressed CO was evaluated for its lipid classes, fatty acid profiles, and tocol contents. In addition, antiradical and antimicrobial properties of CO were evaluated. The amounts of neutral lipids in CO was the highest (∼94.7% of total lipids), followed by glycolipids and phospholipids. The main fatty acids in CO were linoleic and oleic, which comprise together ∼80% of total fatty acids. Stearic and palmitic acids were the main saturated fatty acids. α- and γ-tocopherols and δ-tocotrienol were the main detected tocols. CO had higher antiradical action against DPPH• and galvinoxyl radicals than virgin olive oil. The results of antimicrobial properties revealed that CO inhibited the growth of all tested microorganisms. CO had a drastic effect on the biosynthesis of proteins and lipids in cells of Bacillus subtilis. In consideration of potential utilization, detailed knowledge on the composition and functional properties of CO is of major importance.

  18. Almond (Prunus dulcis (Mill.) D.A. Webb) skins as a potential source of bioactive polyphenols.

    PubMed

    Monagas, Maria; Garrido, Ignacio; Lebrón-Aguilar, Rosa; Bartolome, Begoña; Gómez-Cordovés, Carmen

    2007-10-17

    An exhaustive study of the phenolic composition of almond ( Prunus dulcis (Mill.) D.A. Webb) skins was carried out in order to evaluate their potential application as a functional food ingredient. Using the HPLC-DAD/ESI-MS technique, a total of 33 compounds corresponding to flavanols, flavonols, dihydroflavonols and flavanones, and other nonflavonoid compounds were identified. Peaks corresponding to another 23 structure-related compounds were also detected. MALDI-TOF MS was applied to characterize almond skin proanthocyanidins, revealing the existence of a series of A- and B-type procyanidins and propelargonidins up to heptamers, and A- and B-type prodelphinidins up to hexamers. Flavanols and flavonol glycosides were the most abundant phenolic compounds in almond skins, representing up to 38-57% and 14-35% of the total quantified phenolics, respectively. Due to their antioxidant properties, measured as oxygen-radical absorbance capacity (ORAC) at 0.398-0.500 mmol Trolox/g, almond skins can be considered as a value-added byproduct for elaborating dietary antioxidant ingredients.

  19. Vitis vinifera L. cv Pinot noir pomace and lees as potential sources of bioactive compounds.

    PubMed

    Reis, Gabriel M; Faccin, Henrique; Viana, Carine; Rosa, Marcelo Barcellos da; de Carvalho, Leandro M

    2016-11-01

    Food and agricultural industries generate substantial quantities of phenolic-rich by-products that could be valuable natural sources of antioxidants. The aim of this study was to identify and quantify the phenolic compounds and radical scavenging activities of two by-products (pomace and lees) from Vitis vinifera L. cv Pinot noir. We found a different distribution of phenolic classes (flavanols, flavonols, phenolic acids and stilbenes) and singular scavenging activity against free radicals (hydroxyl, superoxide and peroxyl radicals). The major class of phenolics in pomace was flavanols and in lees was flavonols, with catechin (117.9 ± 2.5 μg g(-1)) and quercetin (42.4 ± 1.2 μg g(-1)) being the most abundant individual compounds. We also found high potential on scavenging activity against superoxide radicals in pomace (80% of scavenging activity) and radical peroxyl (67% scavenging activity). These results show the possibility of using Pinot noir by-products as promising additives or as a source for the development of new products in different segments of the food and cosmetic industries.

  20. Novel bioactive tetracycline-containing electrospun polymer fibers as a potential antibacterial dental implant coating.

    PubMed

    Shahi, R G; Albuquerque, M T P; Münchow, E A; Blanchard, S B; Gregory, R L; Bottino, M C

    2016-09-01

    The purpose of this investigation was to determine the ability of tetracycline-containing fibers to inhibit biofilm formation of peri-implantitis-associated pathogens [i.e., Porphyromonas gingivalis (Pg), Fusobacterium nucleatum (Fn), Prevotella intermedia (Pi), and Aggregatibacter actinomycetemcomitans (Aa)]. Tetracycline hydrochloride (TCH) was added to a poly(DL-lactide) [PLA], poly(ε-caprolactone) [PCL], and gelatin [GEL] polymer blend solution at distinct concentrations to obtain the following fibers: PLA:PCL/GEL (TCH-free, control), PLA:PCL/GEL + 5 % TCH, PLA:PCL/GEL + 10 % TCH, and PLA:PCL/GEL + 25 % TCH. The inhibitory effect of TCH-containing fibers on biofilm formation was assessed by colony-forming units (CFU/mL). Qualitative analysis of biofilm inhibition was done via scanning electron microscopy (SEM). Statistical significance was reported at p < 0.05. Complete inhibition of biofilm formation on the fibers was observed in groups containing TCH at 10 and 25 wt%. Fibers containing TCH at 5 wt% demonstrated complete inhibition of Aa biofilm. Even though a marked reduction in CFU/mL was observed with an increase in TCH concentration, Pi proved to be the most resilient microorganism. SEM images revealed the absence of or a notable decrease in bacterial biofilm on the TCH-containing nanofibers. Collectively, our data suggest that tetracycline-containing fibers hold great potential as an antibacterial dental implant coating.

  1. Interatomic Potential Models for Ionic Materials

    NASA Astrophysics Data System (ADS)

    Gale, Julian D.

    Ionic materials are present in many key technological applications of the modern era, from solid state batteries and fuel cells, nuclear waste immobiliza tion, through to industrial heterogeneous catalysis, such as that found in automotive exhaust systems. With the boundless possibilities for their utilization, it is natural that there has been a long history of computer simulation of their structure and properties in order to understand the materials science of these systems at the atomic level.

  2. Chiral lactic hydrazone derivatives as potential bioactive antibacterial agents: Synthesis, spectroscopic, structural and molecular docking studies

    NASA Astrophysics Data System (ADS)

    Noshiranzadeh, Nader; Heidari, Azam; Haghi, Fakhri; Bikas, Rahman; Lis, Tadeusz

    2017-01-01

    A series of novel chiral lactic-hydrazone derivatives were synthesized by condensation of (S)-lactic acid hydrazide with salicylaldehyde derivatives and characterized by elemental analysis and spectroscopic studies (FT-IR, 1H NMR and 13C NMR spectroscopy). The structure of one compound was determined by single crystal X-ray analysis. Antibacterial activity of the synthesized compounds was studied against Staphylococcus aureus, Streptococcus pneumonia, Escherichia coli and Pseudomonas aeruginosa as bacterial cultures by broth microdilution method. All of the synthesized compounds showed good antibacterial activity with MIC range of 64-512 μg/mL. Compounds (S,E)-2-hydroxy-N-(2-hydroxy-5-nitrobenzylidene)propanehydrazide (5) and (S,E)-2-hydroxy-N-((3-hydroxy-5-(hydroxymethyl)-2-methylpyridin-4-yl)propanehydrazide (7) were the most effective antibacterial derivatives against S. aureus and E. coli respectively with a MIC value of 64 μg/mL. Bacterial biofilm formation assay showed that these compounds significantly inhibited biofilm formation of P. aeruginosa. Also, in silico molecular docking studies were performed to show lipoteichoic acid synthase (LtaS) inhibitory effect of lactic hydrazone derivatives. The association between electronic and structural effects of some substituents on the benzylidene moiety and the biological activity of these chiral compounds were studied. Structural studies show that compound with higher hydrogen bonding interactions show higher antibacterial activity. The results show chiral hydrazone derivatives based on lactic acid hydrazide could be used as potential lead compounds for developing novel antibacterial agents.

  3. In silico target fishing for the potential bioactive components contained in Huanglian Jiedu Tang (HLJDD) and elucidating molecular mechanisms for the treatment of sepsis.

    PubMed

    Ma, Shi-Tang; Feng, Cheng-Tao; Dai, Guo-Liang; Song, Yue; Zhou, Guo-Liang; Zhang, Xiao-Lin; Miao, Cheng-Gui; Yu, Hao; Ju, Wen-Zheng

    2015-01-01

    The present study was designed to target fish for potential bioactive components contained in a Huang Lian Jie Du decoction (HLJDD) and identify the underlying mechanisms of action for the treatment of sepsis at the molecular level. he bioactive components database of HLJDD was constructed and the sepsis-associated targets were comprehensively investigated. The 3D structures of the PAFR and TXA2R proteins were established using the homology modelling (HM) method, and the molecular effects for sepsis treatment were analysed by comparing the bioactive components database and the sepsis targets using computational biology methods. The results of the screening were validated with biological testing against the human oral epidermal carcinoma cell line KB in vitro. We found that multiple bioactive compounds contained in the HLJDD interacted with multiple targets. We also predicted the promising compound leads for sepsis treatment, and the first 28 compounds were characterized. Several compounds, such as berberine, berberrubine and epiberberine, dose-dependently inhibited PGE2 production in human KB cells, and the effects were similar in the presence or absence of TPA. This study demonstrates a novel approach to identifying natural chemical compounds as new leads for the treatment of sepsis. Copyright © 2015 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  4. Electrospun Polyhydroxybutyrate/Poly(ε-caprolactone)/58S Sol-Gel Bioactive Glass Hybrid Scaffolds with Highly Improved Osteogenic Potential for Bone Tissue Engineering.

    PubMed

    Ding, Yaping; Li, Wei; Müller, Teresa; Schubert, Dirk W; Boccaccini, Aldo R; Yao, Qingqing; Roether, Judith A

    2016-07-13

    Electrospinning of biopolymer and inorganic substances is one of the efficient ways to combine various advantageous properties in one single fibrous structure with potential for tissue engineering applications. In the present study, to integrate the high stiffness of polyhydroxybutyrate (PHB), the flexibility of poly(ε-caprolactone) (PCL) and the bioactivity of 58S bioactive glass, PHB/PCL/58S sol-gel bioactive glass hybrid scaffolds were fabricated using combined electrospinning and sol-gel method. Physical features such as fiber diameter distribution, mechanical strength and Young's modulus were characterized thoroughly. FTIR analysis demonstrated the successful incorporation of 58S bioactive glass into the blend polymers, which greatly improved the hydrophilicity of PHB/PCL fibermats. The primary biological response of MG-63 osteoblast-like cells on the prepared fibrous scaffolds was evaluated, proving that the 58S glass sol containing hybrid scaffold were not only favorable to MG-63 cell adhesion but also slightly enhanced cell viability and significantly increased alkaline phosphate activity .

  5. Enhanced apatite-forming ability and antibacterial activity of porous anodic alumina embedded with CaO-SiO2-Ag2O bioactive materials.

    PubMed

    Ni, Siyu; Li, Xiaohong; Yang, Pengan; Ni, Shirong; Hong, Feng; Webster, Thomas J

    2016-01-01

    In this study, to provide porous anodic alumina (PAA) with bioactivity and anti-bacterial properties, sol-gel derived bioactive CaO-SiO2-Ag2O materials were loaded onto and into PAA nano-pores (termed CaO-SiO2-Ag2O/PAA) by a sol-dipping method and subsequent calcination of the gel-glasses. The in vitro apatite-forming ability of the CaO-SiO2-Ag2O/PAA specimens was evaluated by soaking them in simulated body fluid (SBF). The surface microstructure and chemical property before and after soaking in SBF were characterized. Release of ions into the SBF was also measured. In addition, the antibacterial properties of the samples were tested against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The results showed that CaO-SiO2-Ag2O bioactive materials were successfully decorated onto and into PAA nano-pores. In vitro SBF experiments revealed that the CaO-SiO2-Ag2O/PAA specimens dramatically enhanced the apatite-forming ability of PAA in SBF and Ca, Si and Ag ions were released from the samples in a sustained and slow manner. Importantly, E. coli and S. aureus were both killed on the CaO-SiO2-Ag2O/PAA (by 100%) samples compared to PAA controls after 3 days of culture. In summary, this study demonstrated that the CaO-SiO2-Ag2O/PAA samples possess good apatite-forming ability and high antibacterial activity causing it to be a promising bioactive coating candidate for implant materials for orthopedic applications.

  6. Dendrimer-modified solid supports: nanostructured materials with potential drug allergy diagnostic applications.

    PubMed

    Ruiz-Sanchez, A J; Montañez, M I; Mayorga, C; Torres, M J; Kehr, N S; Vida, Y; Collado, D; Najera, F; De Cola, L; Perez-Inestrosa, E

    2012-01-01

    Complex functional materials consisting of bioactive molecules immobilized on solid supports present potential applications in biosensoring. Advances in the fabrication of these surface materials are of growing interest for antibody-based diagnosis. This work exploits dendrimers as versatile nanostructures for templating sensor surfaces and the critical role of the immobilization protocol in the solid supports cellulose and zeolites, of organic and inorganic composition respectively. The fabrication and characterization, including the degree of functionalization and reproducibility, of different nanostructured materials are described. To validate the approach, the fabricated supports were further used as a solid phase for developing a radioimmunoassay to detect immunoglobulin E (IgE) specific to penicillin, the antibody involved in immediate allergy responses to this drug. The dendrimer-modified supports provide assays with significantly enhanced sensitivity, as well as increase the availability of biomolecules for specific interaction and minimize nonspecific adsorptions through appropriate functionalization protocols in each case. The manufacturing methodology involved the use of a long, flexible hydrophilic spacer in the cellulose materials, and a higher surface density of the immobilized dendrimers in the zeolite crystals. The ability of hybrid zeolite materials in such biosensing applications was evaluated for the first time. The assays were validated in human serum samples from patients allergic to penicillin and from non-allergic controls. The specificity and improved sensitivity of the dendrimer- modified supports make these strategies versatile for different bioactive molecules and could have significant implications for the quantification of a wide range of specific IgE antibodies and other biomolecules of diagnostic interest.

  7. Screening Method for the Discovery of Potential Bioactive Cysteine-Containing Peptides Using 3D Mass Mapping.

    PubMed

    van Oosten, Luuk N; Pieterse, Mervin; Pinkse, Martijn W H; Verhaert, Peter D E M

    2015-12-01

    Animal venoms and toxins are a valuable source of bioactive peptides with pharmacologic relevance as potential drug leads. A large subset of biologically active peptides discovered up till now contain disulfide bridges that enhance stability and activity. To discover new members of this class of peptides, we developed a workflow screening specifically for those peptides that contain inter- and intra-molecular disulfide bonds by means of three-dimensional (3D) mass mapping. Two intrinsic properties of the sulfur atom, (1) its relatively large negative mass defect, and (2) its isotopic composition, allow for differentiation between cysteine-containing peptides and peptides lacking sulfur. High sulfur content in a peptide decreases the normalized nominal mass defect (NMD) and increases the normalized isotopic shift (NIS). Hence in a 3D plot of mass, NIS, and NMD, peptides with sulfur appear in this plot with a distinct spatial localization compared with peptides that lack sulfur. In this study we investigated the skin secretion of two frog species; Odorrana schmackeri and Bombina variegata. Peptides from the crude skin secretions were separated by nanoflow LC, and of all eluting peptides high resolution zoom scans were acquired in order to accurately determine both monoisotopic mass and average mass. Both the NMD and the NIS were calculated from the experimental data using an in-house developed MATLAB script. Candidate peptides exhibiting a low NMD and high NIS values were selected for targeted de novo sequencing, and this resulted in the identification of several novel inter- and intra-molecular disulfide bond containing peptides. Graphical Abstract ᅟ.

  8. Screening Method for the Discovery of Potential Bioactive Cysteine-Containing Peptides Using 3D Mass Mapping

    NASA Astrophysics Data System (ADS)

    van Oosten, Luuk N.; Pieterse, Mervin; Pinkse, Martijn W. H.; Verhaert, Peter D. E. M.

    2015-12-01

    Animal venoms and toxins are a valuable source of bioactive peptides with pharmacologic relevance as potential drug leads. A large subset of biologically active peptides discovered up till now contain disulfide bridges that enhance stability and activity. To discover new members of this class of peptides, we developed a workflow screening specifically for those peptides that contain inter- and intra-molecular disulfide bonds by means of three-dimensional (3D) mass mapping. Two intrinsic properties of the sulfur atom, (1) its relatively large negative mass defect, and (2) its isotopic composition, allow for differentiation between cysteine-containing peptides and peptides lacking sulfur. High sulfur content in a peptide decreases the normalized nominal mass defect (NMD) and increases the normalized isotopic shift (NIS). Hence in a 3D plot of mass, NIS, and NMD, peptides with sulfur appear in this plot with a distinct spatial localization compared with peptides that lack sulfur. In this study we investigated the skin secretion of two frog species; Odorrana schmackeri and Bombina variegata. Peptides from the crude skin secretions were separated by nanoflow LC, and of all eluting peptides high resolution zoom scans were acquired in order to accurately determine both monoisotopic mass and average mass. Both the NMD and the NIS were calculated from the experimental data using an in-house developed MATLAB script. Candidate peptides exhibiting a low NMD and high NIS values were selected for targeted de novo sequencing, and this resulted in the identification of several novel inter- and intra-molecular disulfide bond containing peptides.

  9. Screening of in vitro cytotoxicity, antioxidant potential and bioactivity of nano- and micro-ZrO2 and -TiO2 particles.

    PubMed

    Karunakaran, Gopalu; Suriyaprabha, Rangaraj; Manivasakan, Palanisamy; Yuvakkumar, Rathinam; Rajendran, Venkatachalam; Kannan, Narayanasamy

    2013-07-01

    Nanometal oxides are used in tissue engineering and implants. The increased use of nanoparticles suggests the need to study their adverse effects on biological systems. The present investigation explores in vitro cytotoxicity, antioxidant potential, and bioactivity of nano- and micro-particles such as zirconia (ZrO2) and titania (TiO2) on biological systems such as National Institute of Health (NIH) 3T3 mouse embryonic fibroblasts cell line, di(phenyl)-(2,4,6-trinitrophenyl) iminoazanium (DPPH) and simulated body fluid (SBF). The cell line viability % indicated that nano ZrO2 and TiO2 were less toxic than microparticles up to 200µgml(-1). DPPH assay revealed that the free radical scavenging potential of tested particles were higher for nano ZrO2 (76.9%) and nano TiO2 (73.3%) at 100mg than that for micron size particles. Calcium deposition percentage of micro- and nano-ZrO2 particles, after SBF study, showed 0.066% and 0.094% respectively, whereas for micro- and nano-TiO2, it was 0.251% and 0.615% respectively. FTIR results showed a good bioactivity through hydroxyapatite formation. The present investigation clearly shows that nanoparticles possess good antioxidant potential and better biocompatibility under in vitro conditions which are dose and size dependent. Hence, cytotoxicity itself is not promising evaluation method for toxicity rather than particles individual characterisation using antioxidant and bioactivity analysis.

  10. New generation poly(ε-caprolactone)/gel-derived bioactive glass composites for bone tissue engineering: Part I. Material properties.

    PubMed

    Dziadek, Michal; Menaszek, Elzbieta; Zagrajczuk, Barbara; Pawlik, Justyna; Cholewa-Kowalska, Katarzyna

    2015-11-01

    Poly(ε-caprolactone) (PCL) based composite films containing 12 and 21vol.% bioactive glass (SBG) microparticles were prepared by solvent casting method. Two gel-derived SBGs of SiO2-CaO-P2O5 system differing in SiO2 and CaO contents were applied (mol%): S2: 80SiO2, 16CaO, 4P2O5 and A2: 40SiO2, 54CaO, 6P2O5. The surfaces of the films in contact with Petri dish and exposed to the gas phase during casting were denoted as GS and AS, respectively. Both surfaces of films were characterised in terms of their morphology, micro- and nano-topography as well as wettability. Also mechanical properties (tensile strength, Young's modulus) and PCL matrix crystallinity (degree of crystallinity, crystal size) were evaluated. Degradation behaviour was examined by incubation of materials in UHQ-water at 37°C for 56weeks. The crystallinity, melting temperature and mass loss of incubated materials and pH changes of water were monitored. Furthermore, proliferation of MG-63 osteoblastic cells by direct contact and cytotoxic effect of obtained materials were investigated. Results showed that opposite surfaces of the same polymer and composite films differ in studied surface parameters. The addition of SBG particles into PCL matrix improves nano- and micro-roughness of both surfaces, enhances the hydrophilicity of GS surfaces (~67° for 21A2-PCL compared to ~78° for pure PCL) and also makes AS surface more hydrophobic (~94° for 21S2-PCL compared to ~86° for pure PCL). The nucleation density of PCL was increased with increasing content of SBG particles, which results in the large number of fine spherulites on composite AS surfaces observed using polarized optical (POM), scanning electron (SEM), and atomic force (AFM) microscopies. Higher content of SBG particles causes a notable increase of Young's modulus (from 0.38GPa for pure PCL, 0.90GPa for 12A2-PCL to 1.31GPa for 21A2-PCL), which also depends on SBG chemical composition. After 56-week degradation test, considerably higher

  11. Some characteristics of potential backfill materials

    SciTech Connect

    Simpson, D.R.

    1983-05-01

    A backfill material is one of the multiple barriers that may be involved in the disposal of nuclear waste. Such backfill should be a desiccant with the hydrous product having acceptable stability; it should sorb any released radioisotopes, and it should reseal any breached site. The backfill must also have acceptable thermal conductivity. This report presents data on the rate of hydration and the nature of the product of reaction of some candidate backfill materials with water and with brine. Thermal conductivity data is reported for both the reactants and the products. Granular MgO at 150/sup 0/C completely hydrates in less than 10 hours. At 60/sup 0/C and 20/sup 0/C, such extensive hydration requires about 100 and 1000 hours, respectively. The product of the reaction is stable to more than 300/sup 0/C. A doped discalcium silicate was less reactive and the product contains less water of crystallization than the MgO. The reaction product of dicalcium silicate is cementous, but it has low thermal stability. Bentonite readily reacts with water and expands. The reaction product has the properties of vermiculite, which indicates that magnesium ions have diffused into the bentonite structure and are not simply adsorbed on the surface. If bentonite is emplaced in a saline environment, the properties of vermiculite, the reaction product, should also be considered. The thermal conductivity of MgO, discalcium silicate, and bentonite is primarily dependent on the porosity of the sample. A slight increase in thermal conductivity was found with increased temperature, in contrast to most rocks. If the conductive data for the different materials is equated to the same porosity, MgO has the superior thermal conductivity compared to bentonite or discalcium silicate.

  12. Materials Evaluated as Potential Soil Stabilizers

    DTIC Science & Technology

    1977-09-01

    21.0 168 270 +153 Lithium hydroxide 0.59 20.8 168 198 +85 Sodium sulfite 1.0 21.2 168 322 +200 Sodium carbonate 1.0 20.5 168 375 +250 Sodium bicarbonate...fluoride, sodium 1.0, and 2.0% rates fluoborate , and sodium tetraborate Mixing Material Form* Type of Soil Treated Capability Powder Silt Good Effective...used (sodiun fluosilicate, sodium fluoride, sodium fluoborate , ET-218, and sodium tetraborate) were either detrimental when added to the cement or no

  13. Utilizing food effects to overcome challenges in delivery of lipophilic bioactives: structural design of medical and functional foods.

    PubMed

    McClements, David Julian

    2013-12-01

    The oral bioavailability of many lipophilic bioactives, such as pharmaceuticals and nutraceuticals, is relatively low due to their poor solubility, permeability and/or chemical stability within the human gastrointestinal tract (GIT). The oral bioavailability of lipophilic bioactives can be improved by designing food matrices that control their release, solubilization, transport and absorption within the GIT. This article discusses the challenges associated with delivering lipophilic bioactive components, the impact of food composition and structure on oral bioavailability and the design of functional and medical foods for improving the oral bioavailability of lipophilic bioactives. Food-based delivery systems can be used to improve the oral bioavailability of lipophilic bioactives. There are a number of potential advantages to delivering lipophilic bioactives using functional or medical foods: greater compliance than conventional delivery forms; increased bioavailability and efficacy; and reduced variability in biological effects. However, food matrices are structurally complex multicomponent materials and research is still needed to identify optimum structures and compositions for particular bioactives.

  14. Bioactive glass in tissue engineering

    PubMed Central

    Rahaman, Mohamed N.; Day, Delbert E.; Bal, B. Sonny; Fu, Qiang; Jung, Steven B.; Bonewald, Lynda F.; Tomsia, Antoni P.

    2011-01-01

    This review focuses on recent advances in the development and use of bioactive glass for tissue engineering applications. Despite its inherent brittleness, bioactive glass has several appealing characteristics as a scaffold material for bone tissue engineering. New bioactive glasses based on borate and borosilicate compositions have shown the ability to enhance new bone formation when compared to silicate bioactive glass. Borate-based bioactive glasses also have controllable degradation rates, so the degradation of the bioactive glass implant can be more closely matched to the rate of new bone formation. Bioactive glasses can be doped with trace quantities of elements such as Cu, Zn and Sr, which are known to be beneficial for healthy bone growth. In addition to the new bioactive glasses, recent advances in biomaterials processing have resulted in the creation of scaffold architectures with a range of mechanical properties suitable for the substitution of loaded as well as non-loaded bone. While bioactive glass has been extensively investigated for bone repair, there has been relatively little research on the application of bioactive glass to the repair of soft tissues. However, recent work has shown the ability of bioactive glass to promote angiogenesis, which is critical to numerous applications in tissue regeneration, such as neovascularization for bone regeneration and the healing of soft tissue wounds. Bioactive glass has also been shown to enhance neocartilage formation during in vitro culture of chondrocyte-seeded hydrogels, and to serve as a subchondral substrate for tissue-engineered osteochondral constructs. Methods used to manipulate the structure and performance of bioactive glass in these tissue engineering applications are analyzed. PMID:21421084

  15. 3D descriptors calculation and conformational search to investigate potential bioactive conformations, with application in 3D-QSAR and virtual screening in drug design.

    PubMed

    da Silva, Carlos Henrique Tomich de Paula; Taft, Carlton Anthony

    2017-10-01

    The knowledge of the bioactive conformation for an active hit is relevant because of the easier interpretation and the general quality of the recognition models of protein and ligand. With the aim of investigating potential bioactive conformations without previous structural knowledge of the molecular target, we present herewith a 'protocol' that could be used which includes generation of low-energy conformations, calculations of tridimensional descriptors and investigation of structural similarity via principal component analysis. The protocol was used in the search for potential bioactive conformations. An initial selection of targets was made from a set of protein-ligand complexes with structure deposited in the Protein Data Bank, which was systematically filtered by lead-like rules, resulting in 45 ligands of 8 important therapeutic targets. After extensive optimization of the protocol and parameters of both OMEGA and Pentacle softwares, the best results were obtained for series of compounds such as the beta-trypsin and urokinase inhibitors, which are more structurally related among each other, inside the respective therapeutic class. Future improvements of the protocol, including a suitable choice and combination of robust 3D descriptors, could yield more reliable and less restrictive results, with general and diverse applications in drug design, in particular for improving the 3D-QSAR methodologies as well as virtual screening experiments for a more reliable selection of new lead compounds for different molecular targets.

  16. Study of in vitro bioactivity and mechanical properties of diopside nano-bioceramic synthesized by a facile method using eggshell as raw material.

    PubMed

    Kazemi, Amirhossein; Abdellahi, Majid; Khajeh-Sharafabadi, Armina; Khandan, Amirsalar; Ozada, Neriman

    2017-02-01

    In this study, diopside bioceramic was synthesized using a mechanical milling process and subsequent heat treatment. The simplicity of experiments and also the high energy available in ball milling lead to rapid synthesis of the products in comparison with other synthesis methods. Magnesium oxide (MgO), silicon dioxide (SiO2) and eggshell (as the calcium source) powders were weighted in stoichiometric conditions and milled to initial activation of the surface of the powder's mixture. Then a sintering process was conducted to complete formation of diopside nanopowder and also evaluates its thermal stability. The mechanisms occurred during the synthesis of this bioceramic were carefully investigated. X-Ray diffraction analysis (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermogravimetry (TG), differential thermal analysis (DTA), and inductive coupled plasma atomic emission spectroscopy (ICP-AES) were used for gathering and analyzing data. The ability and rate of apatite formation on the sample surface were evaluated by Simulated Body Fluid (SBF) test, a method that is well recognized to characterize the in vitro bioactivity of ceramic materials. According to the results obtained, the diopside samples had a significant potential to form apatite layer on their surface during soaking in the SBF solution. Besides, the bonding strength of this bioceramic was about 350±7MPa which was almost more than three times of that reported for hydroxyapatite. An excellent fracture toughness of 4±0.3MPam(0.5) was also obtained for this ceramic which was higher than that of previously reported works.

  17. Electrostatic Control of Bioactivity

    SciTech Connect

    Goldberger, Joshua E.; Berns, Eric J.; Bitton, Ronit; Newcomb, Christina J.; Stupp, Samuel I.

    2012-03-15

    The power of independence: When exhibited on the surface of self-assembling peptide-amphiphile nanofibers, the hydrophobic laminin-derived IKVAV epitope induced nanofiber bundling through interdigitation with neighboring fibers and thus decreased the bioactivity of the resulting materials. The inclusion of charged amino acids in the peptide amphiphiles disrupted the tendency to bundle and led to significantly enhanced neurite outgrowth.

  18. Bioactive Potential of Marine Macroalgae from the Central Red Sea (Saudi Arabia) Assessed by High-Throughput Imaging-Based Phenotypic Profiling.

    PubMed

    Kremb, Stephan; Müller, Constanze; Schmitt-Kopplin, Philippe; Voolstra, Christian R

    2017-03-20

    Marine algae represent an important source of novel natural products. While their bioactive potential has been studied to some extent, limited information is available on marine algae from the Red Sea. This study aimed at the broad discovery of new bioactivities from a collection of twelve macroalgal species from the Central Red Sea. We used imaging-based High-Content Screening (HCS) with a diverse spectrum of cellular markers for detailed cytological profiling of fractionated algal extracts. The cytological profiles for 3 out of 60 algal fractions clustered closely to reference inhibitors and showed strong inhibitory activities on the HIV-1 reverse transcriptase in a single-enzyme biochemical assay, validating the suggested biological target. Subsequent chemical profiling of the active fractions of two brown algal species by ultra-high resolution mass spectrometry (FT-ICR-MS) revealed possible candidate molecules. A database query of these molecules led us to groups of compounds with structural similarities, which are suggested to be responsible for the observed activity. Our work demonstrates the versatility and power of cytological profiling for the bioprospecting of unknown biological resources and highlights Red Sea algae as a source of bioactives that may serve as a starting point for further studies.

  19. Bioactive Potential of Marine Macroalgae from the Central Red Sea (Saudi Arabia) Assessed by High-Throughput Imaging-Based Phenotypic Profiling

    PubMed Central

    Kremb, Stephan; Müller, Constanze; Schmitt-Kopplin, Philippe; Voolstra, Christian R.

    2017-01-01

    Marine algae represent an important source of novel natural products. While their bioactive potential has been studied to some extent, limited information is available on marine algae from the Red Sea. This study aimed at the broad discovery of new bioactivities from a collection of twelve macroalgal species from the Central Red Sea. We used imaging-based High-Content Screening (HCS) with a diverse spectrum of cellular markers for detailed cytological profiling of fractionated algal extracts. The cytological profiles for 3 out of 60 algal fractions clustered closely to reference inhibitors and showed strong inhibitory activities on the HIV-1 reverse transcriptase in a single-enzyme biochemical assay, validating the suggested biological target. Subsequent chemical profiling of the active fractions of two brown algal species by ultra-high resolution mass spectrometry (FT-ICR-MS) revealed possible candidate molecules. A database query of these molecules led us to groups of compounds with structural similarities, which are suggested to be responsible for the observed activity. Our work demonstrates the versatility and power of cytological profiling for the bioprospecting of unknown biological resources and highlights Red Sea algae as a source of bioactives that may serve as a starting point for further studies. PMID:28335513

  20. Reprint of: Review of bioactive glass: From Hench to hybrids.

    PubMed

    Jones, Julian R

    2015-09-01

    Bioactive glasses are reported to be able to stimulate more bone regeneration than other bioactive ceramics but they lag behind other bioactive ceramics in terms of commercial success. Bioactive glass has not yet reached its potential but research activity is growing. This paper reviews the current state of the art, starting with current products and moving onto recent developments. Larry Hench's 45S5 Bioglass® was the first artificial material that was found to form a chemical bond with bone, launching the field of bioactive ceramics. In vivo studies have shown that bioactive glasses bond with bone more rapidly than other bioceramics, and in vitro studies indicate that their osteogenic properties are due to their dissolution products stimulating osteoprogenitor cells at the genetic level. However, calcium phosphates such as tricalcium phosphate and synthetic hydroxyapatite are more widely used in the clinic. Some of the reasons are commercial, but others are due to the scientific limitations of the original Bioglass 45S5. An example is that it is difficult to produce porous bioactive glass templates (scaffolds) for bone regeneration from Bioglass 45S5 because it crystallizes during sintering. Recently, this has been overcome by understanding how the glass composition can be tailored to prevent crystallization. The sintering problems can also be avoided by synthesizing sol-gel glass, where the silica network is assembled at room temperature. Process developments in foaming, solid freeform fabrication and nanofibre spinning have now allowed the production of porous bioactive glass scaffolds from both melt- and sol-gel-derived glasses. An ideal scaffold for bone regeneration would share load with bone. Bioceramics cannot do this when the bone defect is subjected to cyclic loads, as they are brittle. To overcome this, bioactive glass polymer hybrids are being synthesized that have the potential to be tough, with congruent degradation of the bioactive inorganic and

  1. Review of bioactive glass: from Hench to hybrids.

    PubMed

    Jones, Julian R

    2013-01-01

    Bioactive glasses are reported to be able to stimulate more bone regeneration than other bioactive ceramics but they lag behind other bioactive ceramics in terms of commercial success. Bioactive glass has not yet reached its potential but research activity is growing. This paper reviews the current state of the art, starting with current products and moving onto recent developments. Larry Hench's 45S5 Bioglass® was the first artificial material that was found to form a chemical bond with bone, launching the field of bioactive ceramics. In vivo studies have shown that bioactive glasses bond with bone more rapidly than other bioceramics, and in vitro studies indicate that their osteogenic properties are due to their dissolution products stimulating osteoprogenitor cells at the genetic level. However, calcium phosphates such as tricalcium phosphate and synthetic hydroxyapatite are more widely used in the clinic. Some of the reasons are commercial, but others are due to the scientific limitations of the original Bioglass 45S5. An example is that it is difficult to produce porous bioactive glass templates (scaffolds) for bone regeneration from Bioglass 45S5 because it crystallizes during sintering. Recently, this has been overcome by understanding how the glass composition can be tailored to prevent crystallization. The sintering problems can also be avoided by synthesizing sol-gel glass, where the silica network is assembled at room temperature. Process developments in foaming, solid freeform fabrication and nanofibre spinning have now allowed the production of porous bioactive glass scaffolds from both melt- and sol-gel-derived glasses. An ideal scaffold for bone regeneration would share load with bone. Bioceramics cannot do this when the bone defect is subjected to cyclic loads, as they are brittle. To overcome this, bioactive glass polymer hybrids are being synthesized that have the potential to be tough, with congruent degradation of the bioactive inorganic and

  2. Bioactivity and properties of a dental adhesive functionalized with polyhedral oligomeric silsesquioxanes (POSS) and bioactive glass.

    PubMed

    Rizk, Marta; Hohlfeld, Lisa; Thanh, Loan Tao; Biehl, Ralf; Lühmann, Nicole; Mohn, Dirk; Wiegand, Annette

    2017-09-01

    This study aimed to analyze the effect of infiltrating a commercial adhesive with nanosized bioactive glass (BG-Bi) particles or methacryl-functionalized polyhedral oligomeric silsesquioxanes (POSS) on material properties and bioactivity. An acetone-based dental adhesive (Solobond Plus adhesive, VOCO GmbH, Cuxhaven, Germany) was infiltrated with nanosized bioactive glass particles (0.1 or 1wt%), or with monofunctional or multifunctional POSS particles (10 or 20wt%). Unfilled adhesive served as control. Dispersion and hydrodynamic radius of the nanoparticles were studied by dynamic light scattering. Set specimens were immersed for 28days in artificial saliva at 37°C, and surfaces were mapped for the formation of calcium phospate (Ca/P) precipitates (scanning electron microscopy/energy-dispersive X-ray spectroscopy). Viscosity (rheometry) and the structural characteristic of the networks were studied, such as degree of conversion (FTIR spectroscopy), sol fraction and water sorption. POSS particles showed a good dispersion of the particles for both types of particles being smaller than 3nm, while the bioactive glass particles had a strong tendency to agglomerate. All nanoparticles induced the formation of Ca/P precipitates. The viscosity of the adhesive was not or only slightly increased by POSS particle addition but strongly increased by the bioactive glass particles. The degree of conversion, water sorption and sol fraction showed a maintained or improved network structure and properties when filled with BG-Bi and multifunctional POSS, however, less polymerization was found when loading a monofunctional POSS. Multifunctional POSS may be incorporated into dental adhesives to provide a bioactive potential without changing material properties adversely. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  3. Preparation method: structure-bioactivity correlation in mesoporous bioactive glass

    NASA Astrophysics Data System (ADS)

    Shih, Shao-Ju; Chou, Yu-Jen; Borisenko, Konstantin B.

    2013-06-01

    Mesoporous bioactive glasses (MBGs) are receiving increased attention because of their superior bioactive properties and possible applications as drug-releasing carriers, bone implants and sealing materials in dentistry. We report here the results of investigation of structures and bioactivities of two types of MBG particles prepared by two different techniques, the sol-gel method and spray pyrolysis (SP). In this study, we used transmission electron microscopy and selected area electron diffraction to characterize particle morphology and atomistic structures of the particles correlating these observations with nitrogen adsorption measurements to determine surface areas of the particles and in vitro bioactivity tests. It is found that the preparation method can influence the final composition of the particles and that SP method offers a better control over the composition. The SP particles have higher bioactivity than the sol-gel particles due to their higher surface area and possibly more favourable atomistic structure for promoting deposition of pure hydroxyl apatite phase.

  4. Leishmanicidal Activity of Piper nigrum Bioactive Fractions is Interceded via Apoptosis In Vitro and Substantiated by Th1 Immunostimulatory Potential In Vivo

    PubMed Central

    Chouhan, Garima; Islamuddin, Mohammad; Want, Muzamil Y.; Ozbak, Hani A.; Hemeg, Hassan A.; Sahal, Dinkar; Afrin, Farhat

    2015-01-01

    Visceral leishmaniasis (VL) is a life-threatening protozoal infection chiefly impinging the rural and poor population in the tropical and sub-tropical countries. The deadly affliction is rapidly expanding after its association with AIDS, swiftly defying its status of a neglected disease. Despite successful formulation of vaccine against canine leishmaniasis, no licensed vaccine is yet available for human VL, chemotherapy is in appalling state, and the development of new candidate drugs has been painfully slow. In face of lack of proper incentives, immunostimulatory plant preparations owing antileishmanial efficacy bear potential to rejuvenate awful antileishmanial chemotherapy. We have earlier reported profound leishmanicidal activity of Piper nigrum hexane (PNH) seeds and P. nigrum ethanolic (PNE) fractions derived from P. nigrum seeds against Leishmania donovani promastigotes and amastigotes. In the present study, we illustrate that the remarkable anti-promastigote activity exhibited by PNH and PNE is mediated via apoptosis as evidenced by phosphatidylserine externalization, DNA fragmentation, arrest in sub G0/G1 phase, loss of mitochondrial membrane potential and generation of reactive oxygen species. Further, P. nigrum bioactive fractions rendered significant protection to L. donovani infected BALB/c mice in comparison to piperine, a known compound present in Piper species. The substantial therapeutic potential of PNH and PNE was accompanied by elicitation of cell-mediated immune response. The bioactive fractions elevated the secretion of Th1 (INF-γ, TNF-α, and IL-2) cytokines and declined IL-4 and IL-10. PNH and PNE enhanced the production of IgG2a, upregulated the expression of co-stimulatory molecules CD80 and CD86, augmented splenic CD4+ and CD8+ T cell population, induced strong lymphoproliferative and DTH responses and partially stimulated NO production. PNH and PNE were devoid of any hepatic or renal toxicity. These encouraging findings merit further

  5. Leishmanicidal Activity of Piper nigrum Bioactive Fractions is Interceded via Apoptosis In Vitro and Substantiated by Th1 Immunostimulatory Potential In Vivo.

    PubMed

    Chouhan, Garima; Islamuddin, Mohammad; Want, Muzamil Y; Ozbak, Hani A; Hemeg, Hassan A; Sahal, Dinkar; Afrin, Farhat

    2015-01-01

    Visceral leishmaniasis (VL) is a life-threatening protozoal infection chiefly impinging the rural and poor population in the tropical and sub-tropical countries. The deadly affliction is rapidly expanding after its association with AIDS, swiftly defying its status of a neglected disease. Despite successful formulation of vaccine against canine leishmaniasis, no licensed vaccine is yet available for human VL, chemotherapy is in appalling state, and the development of new candidate drugs has been painfully slow. In face of lack of proper incentives, immunostimulatory plant preparations owing antileishmanial efficacy bear potential to rejuvenate awful antileishmanial chemotherapy. We have earlier reported profound leishmanicidal activity of Piper nigrum hexane (PNH) seeds and P. nigrum ethanolic (PNE) fractions derived from P. nigrum seeds against Leishmania donovani promastigotes and amastigotes. In the present study, we illustrate that the remarkable anti-promastigote activity exhibited by PNH and PNE is mediated via apoptosis as evidenced by phosphatidylserine externalization, DNA fragmentation, arrest in sub G0/G1 phase, loss of mitochondrial membrane potential and generation of reactive oxygen species. Further, P. nigrum bioactive fractions rendered significant protection to L. donovani infected BALB/c mice in comparison to piperine, a known compound present in Piper species. The substantial therapeutic potential of PNH and PNE was accompanied by elicitation of cell-mediated immune response. The bioactive fractions elevated the secretion of Th1 (INF-γ, TNF-α, and IL-2) cytokines and declined IL-4 and IL-10. PNH and PNE enhanced the production of IgG2a, upregulated the expression of co-stimulatory molecules CD80 and CD86, augmented splenic CD4(+) and CD8(+) T cell population, induced strong lymphoproliferative and DTH responses and partially stimulated NO production. PNH and PNE were devoid of any hepatic or renal toxicity. These encouraging findings merit

  6. Novel bioresorbable and bioactive composites based on bioactive glass and polylactide foams for bone tissue engineering.

    PubMed

    Roether, J A; Gough, J E; Boccaccini, A R; Hench, L L; Maquet, V; Jérôme, R

    2002-12-01

    Bioresorbable and bioactive tissue engineering scaffolds based on bioactive glass (45S5 Bioglass(R)) particles and macroporous poly(DL-lactide) (PDLLA) foams were fabricated. A slurry dipping technique in conjunction with pretreatment in ethanol was used to achieve reproducible and well adhering bioactive glass coatings of uniform thickness on the internal and external surfaces of the foams. In vitro studies in simulated body fluid (SBF) demonstrated rapid hydroxyapatite (HA) formation on the surface of the composites, indicating their bioactivity. For comparison, composite foams containing Bioglass(R) particles as filler for the polymer matrix (in concentration of up to 40 wt %) were prepared by freeze-drying, enabling homogenous glass particle distribution in the polymer matrix. The formation of HA on the composite surfaces after immersion in phosphate buffer saline (PBS) was investigated to confirm the bioactivity of the composites. Human osteoblasts (HOBs) were seeded onto as-fabricated PDLLA foams and onto PDLLA foams coated with Bioglass(R) particles to determine early cell attachment and spreading. Cells were observed to attach and spread on all surfaces after the first 90 min in culture. The results of this study indicate that the fabricated composite materials have potential as scaffolds for guided bone regeneration.

  7. Fluoride-containing bioactive glasses: Glass design, structure, bioactivity, cellular interactions, and recent developments.

    PubMed

    Shah, Furqan A

    2016-01-01

    Bioactive glasses (BGs) are known to bond to both hard and soft tissues. Upon exposure to an aqueous environment, BG undergoes ion exchange, hydrolysis, selective dissolution and precipitation of an apatite layer on their surface, which elicits an interfacial biological response resulting in bioactive fixation, inhibiting further dissolution of the glass, and preventing complete resorption of the material. Fluorine is considered one of the most effective in-vivo bone anabolic factors. In low concentrations, fluoride ions (F(-)) increase bone mass and mineral density, improve the resistance of the apatite structure to acid attack, and have well documented antibacterial properties. F(-) ions may be incorporated into the glass in the form of calcium fluoride (CaF2) either by part-substitution of network modifier oxides, or by maintaining the ratios of the other constituents relatively constant. Fluoride-containing bioactive glasses (FBGs) enhance and control osteoblast proliferation, differentiation and mineralisation. And with their ability to release fluoride locally, FBGs make interesting candidates for various clinical applications, dentinal tubule occlusion in the treatment of dentin hypersensitivity. This paper reviews the chemistry of FBGs and the influence of F(-) incorporation on the thermal properties, bioactivity, and cytotoxicity; and novel glass compositions for improved mechanical properties, processing, and bioactive potential.

  8. Gene delivery nanocarriers of bioactive glass with unique potential to load BMP2 plasmid DNA and to internalize into mesenchymal stem cells for osteogenesis and bone regeneration

    NASA Astrophysics Data System (ADS)

    Kim, Tae-Hyun; Singh, Rajendra K.; Kang, Min Sil; Kim, Joong-Hyun; Kim, Hae-Won

    2016-04-01

    The recent development of bioactive glasses with nanoscale morphologies has spurred their specific applications in bone regeneration, for example as drug and gene delivery carriers. Bone engineering with stem cells genetically modified with this unique class of nanocarriers thus holds great promise in this avenue. Here we report the potential of the bioactive glass nanoparticle (BGN) system for the gene delivery of mesenchymal stem cells (MSCs) targeting bone. The composition of 15% Ca-added silica, proven to be bone-bioactive, was formulated into surface aminated mesoporous nanospheres with enlarged pore sizes, to effectively load and deliver bone morphogenetic protein-2 (BMP2) plasmid DNA. The enlarged mesopores were highly effective in loading BMP2-pDNA with an efficiency as high as 3.5 wt% (pDNA w.r.t. BGN), a level more than twice than for small-sized mesopores. The BGN nanocarriers released the genetic molecules in a highly sustained manner (for as long as 2 weeks). The BMP2-pDNA/BGN complexes were effectively internalized to rat MSCs with a cell uptake level of ~73%, and the majority of cells were transfected to express the BMP2 protein. Subsequent osteogenesis of the transfected MSCs was demonstrated by the expression of bone-related genes, including bone sialoprotein, osteopontin, and osteocalcin. The MSCs transfected with BMP2-pDNA/BGN were locally delivered inside a collagen gel to the target calvarium defects. The results showed significantly improved bone regeneration, as evidenced by the micro-computed tomographic, histomorphometric and immunohistochemical analyses. This study supports the excellent capacity of the BGN system as a pDNA-delivery nanocarrier in MSCs, and the engineered system, BMP2-pDNA/BGN with MSCs, may be considered a new promising candidate to advance the therapeutic potential of stem cells through genetic modification, targeting bone defects and diseases.The recent development of bioactive glasses with nanoscale morphologies has

  9. Anti-fouling bioactive surfaces.

    PubMed

    Yu, Qian; Zhang, Yanxia; Wang, Hongwei; Brash, John; Chen, Hong

    2011-04-01

    Bioactive surfaces refer to surfaces with immobilized bioactive molecules aimed specifically at promoting or supporting particular interactions. Such surfaces are of great importance for various biomedical and biomaterials applications. In the past few years, considerable effort has been made to create bioactive surfaces by forming specific biomolecule-modified surfaces on a non-biofouling "base" or "background". Hydrophilic and bioinert polymers have been widely used as anti-fouling layers that resist non-specific protein interactions. They can also serve as "spacers" to effectively move the immobilized biomolecule away from the surface, thus enhancing its bioactivity. In this review we summarize several successful approaches for the design and preparation of bioactive surfaces based on different types of anti-fouling/spacer materials. Some perspectives on future research in this area are also presented.

  10. Brewers' spent grain; bioactivity of phenolic component, its role in animal nutrition and potential for incorporation in functional foods: a review.

    PubMed

    McCarthy, Aoife L; O'Callaghan, Yvonne C; Piggott, Charles O; FitzGerald, Richard J; O'Brien, Nora M

    2013-02-01

    Brewers' spent grain (BSG) is a low-value co-product of the brewing industry produced in large quantities annually. This paper reviews the existing evidence regarding the phenolic component of BSG, focusing on composition, extraction and biofunctions such as antioxidant, anti-atherogenic, anti-inflammatory and anti-carcinogenic activities. Furthermore, the incorporation of BSG in foodstuffs will be discussed, including the use of BSG as an animal feed supplement and the potential of BSG to be incorporated into foods for human consumption. BSG contains hydroxycinnamic acids including ferulic acid, p-coumaric acid and caffeic acid; which have shown bioactivity in the pure form (antioxidant, anti-inflammatory, anti-atherogenic and anti-cancer). Phenolic extracts from BSG have also shown antioxidant potential, by protecting against oxidant-induced DNA damage, possibly by Fe chelation. Studies show that BSG has many benefits when used as a supplement in animal feed, such as increasing milk yield, milkfat content and in providing essential dietary amino acids. The incorporation of BSG in human foods such as cookies and ready-to-eat snacks has resulted in increased protein and fibre contents of the products, where the changes in organoleptic properties are controllable. It can be concluded that the phenolic component of BSG has potential bioactive effects, which are worth pursuing given that the inclusion of BSG into human foodstuffs is viable and beneficial.

  11. Spectroscopic and molecular docking studies on N,N-di-tert-butoxycarbonyl (Boc)-2-amino pyridine: A potential bioactive agent for lung cancer treatment

    NASA Astrophysics Data System (ADS)

    Mohamed Asath, R.; Premkumar, R.; Mathavan, T.; Milton Franklin Benial, A.

    2017-09-01

    Potential energy surface scan was performed and the most stable molecular structure of the N,N-di-tert-butoxycarbonyl (Boc)-2-amino pyridine (DBAP) molecule was predicted. The most stable molecular structure of the molecule was optimized using B3LYP method with cc-pVTZ basis set. Anticancer activity of the DBAP molecule was evaluated by molecular docking analysis. The structural parameters and vibrational wavenumbers were calculated for the optimized molecular structure. The experimental and theoretical wavenumbers were assigned and compared. Ultraviolet-Visible spectrum was simulated and validated experimentally. The molecular electrostatic potential surface was simulated and Fukui function calculations were also carried out to investigate the reactive nature of the DBAP molecule. The natural bond orbital analysis was also performed to probe the intramolecular interactions and confirm the bioactivity of the DBAP molecule. The molecular docking analysis reveals the better inhibitory nature of the DBAP molecule against the epidermal growth factor receptor (EGFR) protein which causes lung cancer. Hence, the present study unveils the structural and bioactive nature of the title molecule. The DBAP molecule was identified as a potential inhibitor against the lung cancer which may be useful in further development of drug designing in the treatment of lung cancer.

  12. Identification of Secondary Metabolite Gene Clusters in the Pseudovibrio Genus Reveals Encouraging Biosynthetic Potential toward the Production of Novel Bioactive Compounds.

    PubMed

    Naughton, Lynn M; Romano, Stefano; O'Gara, Fergal; Dobson, Alan D W

    2017-01-01

    Increased incidences of antimicrobial resistance and the emergence of pan-resistant 'superbugs' have provoked an extreme sense of urgency amongst researchers focusing on the discovery of potentially novel antimicrobial compounds. A strategic shift in focus from the terrestrial to the marine environment has resulted in the discovery of a wide variety of structurally and functionally diverse bioactive compounds from numerous marine sources, including sponges. Bacteria found in close association with sponges and other marine invertebrates have recently gained much attention as potential sources of many of these novel bioactive compounds. Members of the genus Pseudovibrio are one such group of organisms. In this study, we interrogate the genomes of 21 Pseudovibrio strains isolated from a variety of marine sources, for the presence, diversity and distribution of biosynthetic gene clusters (BGCs). We expand on results obtained from antiSMASH analysis to demonstrate the similarity between the Pseudovibrio-related BGCs and those characterized in other bacteria and corroborate our findings with phylogenetic analysis. We assess how domain organization of the most abundant type of BGCs present among the isolates (Non-ribosomal peptide synthetases and Polyketide synthases) may influence the diversity of compounds produced by these organisms and highlight for the first time the potential for novel compound production from this genus of bacteria, using a genome guided approach.

  13. Materials Comparison and Potential Applications of Magnesium in Automobiles

    NASA Astrophysics Data System (ADS)

    Luo, Alan A.

    In this paper, the material properties, structural performance, mass saving potential, design and manufacturing characteristics of magnesium are compared with various competing materials such as cast iron, steel sheet, aluminum alloys and polymers. The current and potential automotive applications of magnesium are reviewed, and the technical challenges for these applications are also discussed. Recent alloy development for powertrain applications and the creep resistance of several experimental magnesium alloys are reviewed.

  14. Potential applications of nanostructured materials in nuclear waste management.

    SciTech Connect

    Braterman, Paul S. (The University of North Texas, Denton, TX); Phol, Phillip Isabio; Xu, Zhi-Ping (The University of North Texas, Denton, TX); Brinker, C. Jeffrey; Yang, Yi; Bryan, Charles R.; Yu, Kui; Xu, Huifang (University of New Mexico, Albuquerque, NM); Wang, Yifeng; Gao, Huizhen

    2003-09-01

    This report summarizes the results obtained from a Laboratory Directed Research & Development (LDRD) project entitled 'Investigation of Potential Applications of Self-Assembled Nanostructured Materials in Nuclear Waste Management'. The objectives of this project are to (1) provide a mechanistic understanding of the control of nanometer-scale structures on the ion sorption capability of materials and (2) develop appropriate engineering approaches to improving material properties based on such an understanding.

  15. Carbon reduction potential from recycling in primary materials manufacturing

    SciTech Connect

    Elliott, R.N.

    1993-12-31

    This study assesses the potential for energy savings and carbon emissions reduction by increasing the recycled content of energy-intensive materials. Aluminum, steel, paper, plastics, and container glass are considered. Government policies to encourage higher recycling rates and increased recycled materials content are proposed.

  16. Gene delivery nanocarriers of bioactive glass with unique potential to load BMP2 plasmid DNA and to internalize into mesenchymal stem cells for osteogenesis and bone regeneration.

    PubMed

    Kim, Tae-Hyun; Singh, Rajendra K; Kang, Min Sil; Kim, Joong-Hyun; Kim, Hae-Won

    2016-04-21

    The recent development of bioactive glasses with nanoscale morphologies has spurred their specific applications in bone regeneration, for example as drug and gene delivery carriers. Bone engineering with stem cells genetically modified with this unique class of nanocarriers thus holds great promise in this avenue. Here we report the potential of the bioactive glass nanoparticle (BGN) system for the gene delivery of mesenchymal stem cells (MSCs) targeting bone. The composition of 15% Ca-added silica, proven to be bone-bioactive, was formulated into surface aminated mesoporous nanospheres with enlarged pore sizes, to effectively load and deliver bone morphogenetic protein-2 (BMP2) plasmid DNA. The enlarged mesopores were highly effective in loading BMP2-pDNA with an efficiency as high as 3.5 wt% (pDNA w.r.t. BGN), a level more than twice than for small-sized mesopores. The BGN nanocarriers released the genetic molecules in a highly sustained manner (for as long as 2 weeks). The BMP2-pDNA/BGN complexes were effectively internalized to rat MSCs with a cell uptake level of ∼73%, and the majority of cells were transfected to express the BMP2 protein. Subsequent osteogenesis of the transfected MSCs was demonstrated by the expression of bone-related genes, including bone sialoprotein, osteopontin, and osteocalcin. The MSCs transfected with BMP2-pDNA/BGN were locally delivered inside a collagen gel to the target calvarium defects. The results showed significantly improved bone regeneration, as evidenced by the micro-computed tomographic, histomorphometric and immunohistochemical analyses. This study supports the excellent capacity of the BGN system as a pDNA-delivery nanocarrier in MSCs, and the engineered system, BMP2-pDNA/BGN with MSCs, may be considered a new promising candidate to advance the therapeutic potential of stem cells through genetic modification, targeting bone defects and diseases.

  17. Evaluation of the bone regeneration potential of bioactive glass in implant site development surgeries: a systematic review of the literature.

    PubMed

    Ioannou, Andreas L; Kotsakis, Georgios A; Kumar, Tarun; Hinrichs, James E; Romanos, Georgios

    2015-03-01

    The aim of this systematic review was to assess the efficacy of bioactive glass (BG) in bone regeneration for implant site development procedures. The following specific question was formulated with reference to Population, Intervention, Control, Outcomes (PICO): "In persons that undergo bone regeneration surgeries for implant site development, what histological outcomes does the use of BG yield, alone or in combination with AB, compared to positive or negative controls?". The 1st phase of screening yielded 400 titles and abstracts. A total of 12 studies reporting on the use of bioactive glass were scrutinized for inclusion in the final analysis and 5 studies were selected for qualitative synthesis of the results. Data were divided into two categories: ridge preservation (n = 2) and sinus augmentation (n = 3). Within the limitations of this review, it can be concluded that (1) the combination of BG with AB chips in a 1:1 ratio is an efficacious treatment modality for direct sinus augmentation, with histological results comparable to 100 % AB. (2) When used for ridge preservation, BG yields a high percentage of true bone regeneration. (3) Currently, no reliable controlled studies report histological outcomes from the use of BG in ridge augmentation procedures. Clinicians may consider BG bone substitutes as efficacious alternatives for ridge preservation and sinus augmentation surgical procedures. Further controlled clinical studies are warranted to determine if bone-to-implant contact is improved in BG-grafted sites versus controls.

  18. Potential of pottery materials in manufacturing radioactive waste containers.

    PubMed

    Helal, A A; Alian, A M; Aly, H M; Khalifa, S M

    2003-07-01

    Various pottery materials were evaluated for possible use in manufacturing containers for radioactive waste. Their potential was examined from the viewpoints of the effectiveness of disposal and the changes induced in them by gamma rays. Samples of these materials were irradiated with high-energy neutrons and gamma rays in a reactor near its core. the physical and mechanical properties of the materials before and after gamma irradiation (in a 60Co gamma cell) were compared. The study showed that pottery materials are resistant to radiation. Therefore, they were proposed for manufacturing drums for disposal of radioactive waste of high gamma activity.

  19. Bioactive peptides derived from food.

    PubMed

    Rutherfurd-Markwick, Kay J; Moughan, Paul J

    2005-01-01

    As interest in the ability of functional foods to impact on human health has grown over the past decade, so has the volume of knowledge detailing the beneficial roles of food-derived bioactive peptides. Bioactive peptides from both plant and animal proteins have been discovered, with to date, by far the most being isolated from milk-based products. A wide range of activities has been described, including antimicrobial and antifungal properties, blood pressure-lowering effects, cholesterol-lowering ability, antithrombotic effects, enhancement of mineral absorption, immunomodulatory effects, and localized effects on the gut. Although there is still considerable research to be performed in the area of food-derived bioactive peptides, it is clear that the generation of bioactive peptides from dietary proteins during the normal digestive process is of importance. Therefore, it will become necessary when determining dietary protein quality to consider the potential effects of latent bioactive peptides that are released during digestion of the protein.

  20. Antiaggregation Potential of Padina gymnospora against the Toxic Alzheimer’s Beta-Amyloid Peptide 25–35 and Cholinesterase Inhibitory Property of Its Bioactive Compounds

    PubMed Central

    Shanmuganathan, Balakrishnan; Sheeja Malar, Dicson; Sathya, Sethuraman; Pandima Devi, Kasi

    2015-01-01

    Inhibition of β-amyloid (Aβ) aggregation in the cerebral cortex of the brain is a promising therapeutic and defensive strategy in identification of disease modifying agents for Alzheimer’s disease (AD). Since natural products are considered as the current alternative trend for the discovery of AD drugs, the present study aims at the evaluation of anti-amyloidogenic potential of the marine seaweed Padina gymnospora. Prevention of aggregation and disaggregation of the mature fibril formation of Aβ 25–35 by acetone extracts of P. gymnospora (ACTPG) was evaluated in two phases by Thioflavin T assay. The results were further confirmed by confocal laser scanning microscopy (CLSM) analysis and Fourier transform infrared (FTIR) spectroscopic analysis. The results of antiaggregation and disaggregation assay showed that the increase in fluorescence intensity of aggregated Aβ and the co-treatment of ACTPG (250 μg/ml) with Aβ 25–35, an extensive decrease in the fluorescence intensity was observed in both phases, which suggests that ACTPG prevents the oligomers formation and disaggregation of mature fibrils. In addition, ACTPG was subjected to column chromatography and the bioactivity was screened based on the cholinesterase inhibitory activity. Finally, the active fraction was subjected to LC-MS/MS analysis for the identification of bioactive compounds. Overall, the results suggest that the bioactive compound alpha bisabolol present in the alga might be responsible for the observed cholinesterase inhibition with the IC50 value < 10 μg/ml for both AChE and BuChE when compared to standard drug donepezil (IC50 value < 6 μg/ml) and support its use for the treatment of neurological disorders. PMID:26536106

  1. Bioactivity, proximate, mineral and volatile profiles along the flowering stages of Opuntia microdasys (Lehm.): defining potential applications.

    PubMed

    Chahdoura, Hassiba; Barreira, João C M; Fernández-Ruiz, Virginia; Morales, Patricia; Calhelha, Ricardo C; Flamini, Guido; Soković, Marina; Ferreira, Isabel C F R; Achour, Lotfi

    2016-03-01

    Opuntia spp. flowers have been traditionally used for medical purposes, mostly because of their diversity in bioactive molecules with health promoting properties. The proximate, mineral and volatile compound profiles, together with the cytotoxic and antimicrobial properties were characterized in O. microdasys flowers at different maturity stages, revealing several statistically significant differences. O. microdasys stood out mainly for its high contents of dietary fiber, potassium and camphor, and its high activities against HCT15 cells, Staphylococcus aureus, Aspergillus versicolor and Penicillium funiculosum. The vegetative stage showed the highest cytotoxic and antifungal activities, whilst the full flowering stage was particularly active against bacterial species. The complete dataset has been classified by principal component analysis, achieving clearly identifiable groups for each flowering stage, elucidating also the most distinctive features, and comprehensively profiling each of the assayed stages. The results might be useful to define the best flowering stage considering practical application purposes.

  2. Apoptosis mediated leishmanicidal activity of Azadirachta indica bioactive fractions is accompanied by Th1 immunostimulatory potential and therapeutic cure in vivo.

    PubMed

    Chouhan, Garima; Islamuddin, Mohammad; Want, Muzamil Y; Abdin, Malik Z; Ozbak, Hani A; Hemeg, Hassan A; Sahal, Dinkar; Afrin, Farhat

    2015-03-26

    Exploration of immunomodulatory antileishmanials of plant origin is now being strongly recommended to overcome the immune suppression evident during visceral leishmaniasis (VL) and high cost and toxicity associated with conventional chemotherapeutics. In accordance, we assessed the in vitro and in vivo antileishmanial and immunomodulatory potential of ethanolic fractions of Azadirachta indica leaves (ALE) and seeds (ASE). A. indica fractions were prepared by sequential extraction of the powdered plant parts in hexane, ethanol and water. Erythrosin B staining was employed to appraise the anti-promastigote potential of ALE and ASE. Cytostatic or cytocidal mode of action was ascertained and alterations in parasite morphology were depicted under oil immersion light microscopy. Study of apoptotic correlates was performed to deduce the mechanism of induced cell death and anti-amastigote potential was assessed in Leishmania parasitized RAW 264.7 macrophages. In vivo antileishmanial effectiveness was evaluated in L. donovani infected BALB/c mice, accompanied by investigation of immunomodulatory potential of ALE and ASE. Adverse toxicity of the bioactive fractions against RAW macrophages was studied by MTT assay. In vivo side effects on the liver and kidney functions were also determined. Plant secondary metabolites present in ALE and ASE were analysed by Gas chromatography-mass spectrometry (GC-MS). ALE and ASE (500 μg ml(-1)) exhibited leishmanicidal activity in a time- and dose-dependent manner (IC₅₀ 34 and 77.66 μg ml(-1), respectively) with alterations in promastigote morphology and induction of apoptosis. ALE and ASE exerted appreciable anti-amastigote potency (IC₅₀ 17.66 and 24.66 μg ml(-1), respectively) that was coupled with profound in vivo therapeutic efficacy (87.76% and 85.54% protection in liver and 85.55% and 83.62% in spleen, respectively). ALE exhibited minimal toxicity with selectivity index of 26.10 whereas ASE was observed to be non-toxic. The

  3. The role of silicon on the bioactivity of Skelite(TM) bioceramic: A material and biological characterization of silicon alpha-tricalcium phosphate based ceramics

    NASA Astrophysics Data System (ADS)

    Pietak, Alexis Mari

    Skelite(TM) bioceramics are novel synthetic skeletal replacement materials that participate in the full remodeling process of bone. Skelite contains a high fraction of Silicon Stabilized alpha-Tricalcium Phosphate (Si-TCP), a novel phase to which the unique bioactive properties of Skelite have been attributed. The role of Si in the development of the microporous, interconnected microstructure and mixed phase composition of Skelite was investigated using crystallization kinetics and defect characterization studies. The kinetics of the phase transformation to Si-TCP were studied using rapid thermal processing of thin films on quartz substrates. The results, interpreted using a novel Avrami model, show that Si acts as a nucleation agent for Si-TCP, and also that Si pins the microstructure of the films at higher concentrations. Characterization of defects induced by Si substitution into the phases of Skelite material utilized electron spin resonance (ESR) and thermoluminescence (TL) techniques. These results identify two unique paramagnetic defect centers associated with Si substitution in the hydroxyapatite lattice. Quantification of the relative level of these centers supports a novel chemical model that describes the development of the mixed phase system of Skelite as a function of silica addition. The significance of the Si-TCP phase, sample morphology, and surface chemistry on the activity of osteoclast and osteoblast cells was investigated using cell culture and protein functionalized atomic force microscopy techniques. The biological characterization identifies three interaction mechanisms between Skelite and the biological system. Skelite releases a soluble molecular complex containing Si to the extracellular media, which has a significant bioactive effect on osteoclast and osteoblast growth and activity. Using protein functionalized atomic force microscopy the surface chemistry and reactivity of samples is shown to influence osteopontin affinity for Skelite

  4. Material Discovery and Design with Dynamic Charge Reactive Potentials

    NASA Astrophysics Data System (ADS)

    Sinnott, Susan

    2015-03-01

    Atomic scale computational simulations of multi-phase systems is increasingly important as our ability to simulate nanometer-sized systems becomes routine. The recently developed charge optimized many body potential (COMB) potentials have significantly enhanced our ability to carry out atomic-scale simulations of heterogeneous material systems. The formalism of this potential combines variable charge electrostatic interactions with a classical analytical bond-order potential. It therefore has the capacity to adaptively model metallic, covalent, ionic, and van der Waals bonding within the same simulation cell and dynamically determine the charges on individual atoms according to the local environment. The utility of the COMB potentials is illustrated for materials design and discovery by exploring the structure, stability, mechanical properties, and thermal properties of intermetallic systems and oxide-metal interfaces. They are also used to address key questions associated with corrosion, thin film growth, and heterogeneous catalysis.

  5. Metabolomic-Based Study of the Leafy Gall, the Ecological Niche of the Phytopathogen Rhodococcus Fascians, as a Potential Source of Bioactive Compounds

    PubMed Central

    Nacoulma, Aminata P.; Vandeputte, Olivier M.; De Lorenzi, Manuella; El Jaziri, Mondher; Duez, Pierre

    2013-01-01

    Leafy gall is a plant hyperplasia induced upon Rhodococcus fascians infection. Previously, by genomic and transcriptomic analysis, it has been reported that, at the early stage of symptom development, both primary and secondary metabolisms are modified. The present study is based on the hypothesis that fully developed leafy gall, could represent a potential source of new bioactive compounds. Therefore, non-targeted metabolomic analysis of aqueous and chloroform extracts of leafy gall and non-infected tobacco was carried out by 1H-NMR coupled to principal component analysis (PCA) and orthogonal projections to latent structures-discriminant analysis (OPLS-DA). Polar metabolite profiling reflects modifications mainly in the primary metabolites and in some polyphenolics. In contrast, main modifications occurring in non-polar metabolites concern secondary metabolites, and gas chromatography and mass spectrometry (GC-MS) evidenced alterations in diterpenoids family. Analysis of crude extracts of leafy galls and non-infected tobacco leaves exhibited a distinct antiproliferative activity against all four tested human cancer cell lines. A bio-guided fractionation of chloroformic crude extract yield to semi-purified fractions, which inhibited proliferation of glioblastoma U373 cells with IC50 between 14.0 and 2.4 μg/mL. Discussion is focused on the consequence of these metabolic changes, with respect to plant defense mechanisms following infection. Considering the promising role of diterpenoid family as bioactive compounds, leafy gall may rather be a propitious source for drug discovery. PMID:23771021

  6. Target cell extraction coupled with LC-MS/MS analysis for screening potential bioactive components in Ginkgo biloba extract with preventive effect against diabetic nephropathy.

    PubMed

    Qiu, Jing-ying; Chen, Xu; Zheng, Xiao-xiao; Jiang, Xiang-lan; Yang, Dong-zhi; Yu, Yan-yan; Du, Qian; Tang, Dao-quan; Yin, Xiao-xing

    2015-02-01

    A rapid and useful approach for screening potential bioactive components in Ginkgo biloba extract (GBE) with preventive effect against diabetic nephropathy (DN) was developed using mesangial cells extraction coupled with high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. Mesangial cells were first divided into two groups according to their treatments with high glucose or high glucose plus GBE. After incubation for 4, 8, 12, 16, 24 and 48 h, the cells were harvested and extracted with 40% acetic acid in water before LC-MS/MS analysis. Then, 19 compounds and five metabolites were found to selectively combine with mesangial cells. Notably, compounds including quercetin and rutin were identified or tentatively characterized according to the results of retention time and MS spectra, which is highly consistent with our previous reports that quercetin and rutin are potent protective agents against glomerulosclerosis in DN. Therefore, all these results indicate that target cell extraction coupled with LC-MS/MS analysis can be successfully applied for predicting the bioactive components in GBE with preventive effect against DN. Copyright © 2014 John Wiley & Sons, Ltd.

  7. Metabolomic-based study of the leafy gall, the ecological niche of the phytopathogen Rhodococcus fascians, as a potential source of bioactive compounds.

    PubMed

    Nacoulma, Aminata P; Vandeputte, Olivier M; De Lorenzi, Manuella; Jaziri, Mondher El; Duez, Pierre

    2013-06-14

    Leafy gall is a plant hyperplasia induced upon Rhodococcus fascians infection. Previously, by genomic and transcriptomic analysis, it has been reported that, at the early stage of symptom development, both primary and secondary metabolisms are modified. The present study is based on the hypothesis that fully developed leafy gall, could represent a potential source of new bioactive compounds. Therefore, non-targeted metabolomic analysis of aqueous and chloroform extracts of leafy gall and non-infected tobacco was carried out by 1H-NMR coupled to principal component analysis (PCA) and orthogonal projections to latent structures-discriminant analysis (OPLS-DA). Polar metabolite profiling reflects modifications mainly in the primary metabolites and in some polyphenolics. In contrast, main modifications occurring in non-polar metabolites concern secondary metabolites, and gas chromatography and mass spectrometry (GC-MS) evidenced alterations in diterpenoids family. Analysis of crude extracts of leafy galls and non-infected tobacco leaves exhibited a distinct antiproliferative activity against all four tested human cancer cell lines. A bio-guided fractionation of chloroformic crude extract yield to semi-purified fractions, which inhibited proliferation of glioblastoma U373 cells with IC50 between 14.0 and 2.4 µg/mL. Discussion is focused on the consequence of these metabolic changes, with respect to plant defense mechanisms following infection. Considering the promising role of diterpenoid family as bioactive compounds, leafy gall may rather be a propitious source for drug discovery.

  8. Bioactive Constituents of Zanthoxylum rhetsa Bark and Its Cytotoxic Potential against B16-F10 Melanoma Cancer and Normal Human Dermal Fibroblast (HDF) Cell Lines.

    PubMed

    Santhanam, Ramesh Kumar; Ahmad, Syahida; Abas, Faridah; Safinar Ismail, Intan; Rukayadi, Yaya; Tayyab Akhtar, Muhammad; Shaari, Khozirah

    2016-05-24

    Zanthoxylum rhetsa is an aromatic tree, known vernacularly as "Indian Prickly Ash". It has been predominantly used by Indian tribes for the treatment of many infirmities like diabetes, inflammation, rheumatism, toothache and diarrhea. In this study, we identified major volatile constituents present in different solvent fractions of Z. rhetsa bark using GC-MS analysis and isolated two tetrahydrofuran lignans (yangambin and kobusin), a berberine alkaloid (columbamine) and a triterpenoid (lupeol) from the bioactive chloroform fraction. The solvent fractions and purified compounds were tested for their cytotoxic potential against human dermal fibroblasts (HDF) and mouse melanoma (B16-F10) cells, using the MTT assay. All the solvent fractions and purified compounds were found to be non-cytotoxic to HDF cells. However, the chloroform fraction and kobusin exhibited cytotoxic effect against B16-F10 melanoma cells. The presence of bioactive lignans and alkaloids were suggested to be responsible for the cytotoxic property of Z. rhetsa bark against B16-F10 cells.

  9. Potential structural material problems in a hydrogen energy system

    NASA Technical Reports Server (NTRS)

    Gray, H. R.; Nelson, H. G.; Johnson, R. E.; Mcpherson, B.; Howard, F. S.; Swisher, J. H.

    1975-01-01

    Potential structural material problems that may be encountered in the three components of a hydrogen energy system - production, transmission/storage, and utilization - were identified. Hydrogen embrittlement, corrosion, oxidation, and erosion may occur during the production of hydrogen. Hydrogen embrittlement is of major concern during both transmission and utilization of hydrogen. Specific materials research and development programs necessary to support a hydrogen energy system are described.

  10. Screening of Chonemorpha fragrans Bioactive Extracts for Cytotoxicity Potential and Inhibition Studies of Key Enzymes Involved in Replication

    PubMed Central

    Kedari, Pradnya Prakash; Malpathak, Nutan Padmanabh

    2016-01-01

    Background: Chonemorpha fragrans (Moon) Alston, a liana belonging to family Apocynaceae, is used in traditional medicinal systems for the treatment of various ailments. It is an unexplored medicinal plant with respect to its anticancer potential. Objective: Cytotoxicity of sequential as well as crude extracts of in vivo plant parts (leaves, bark, and roots), in vitro cultures, and callus were compared. Materials and Methods: 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell proliferation assay was used to compare the extracts of various in vivo plant parts (leaves, bark, and roots) along with in vitro culture systems (in vitro plantlets, callus). Furthermore, the extracts were used to evaluate inhibition of key enzymes involved in replication, i.e. topoisomerase (Topo) I and II, DNA polymerase, to check the probable mechanism of action for this cytotoxicity. Results: MTT assay showed that the chloroform extract of callus has potent anticancer potential. The plant has a promising anticancer activity against human colon epithelium, lung carcinoma, and epidermoidal carcinoma cell lines. It was found to possess Topo as well as DNA polymerase inhibitory activity. Conclusion: The results have pointed toward pharmaceutical importance of this plant. This study is the first report of exploring the antiproliferative potential as well as inhibition studies of key enzymes involved in replication, which was useful to point out probable mechanism of action for extracts of C. fragrans. SUMMARY It's a first report of cytotoxicity studies and inhibition of enzyme involved in the replication process by Chonemorpha fragrans plant extracts. The results reveal the pharmaceutical importance of this plant. From various assays performed here, a potent anticancer potential of chloroform extract of callus was revealed showing Topo I (E. coli and human) inhibitory activity, DNA pol inhibitory activity. Considering the importance of these activities, plant further needs

  11. Potential Polymeric Sphere Construction Materials for a Spacecraft Electrostatic Shield

    NASA Technical Reports Server (NTRS)

    Smith, Joseph G., Jr.; Smith, Trent; Williams, Martha; Youngquist, Robert; Mendell, Wendell

    2006-01-01

    An electrostatic shielding concept for spacecraft radiation protection under NASA s Exploration Systems Research and Technology Program was evaluated for its effectiveness and feasibility. The proposed shield design is reminiscent of a classic quadrupole with positively and negatively charged spheres surrounding the spacecraft. The project addressed materials, shield configuration, power supply, and compared its effectiveness to that of a passive shield. The report herein concerns the identification of commercially available materials that could be used in sphere fabrication. It was found that several materials were needed to potentially construct the spheres for an electrostatic shield operating at 300 MV.

  12. A multi-material coating containing chemically-modified apatites for combined enhanced bioactivity and reduced infection via a drop-on-demand micro-dispensing technique.

    PubMed

    Lim, Poon Nian; Wang, Zuyong; Chang, Lei; Konishi, Toshiisa; Choong, Cleo; Ho, Bow; Thian, Eng San

    2017-01-01

    Prevention of infection and enhanced osseointegration are closely related, and required for a successful orthopaedic implant, which necessitate implant designs to consider both criteria in tandem. A multi-material coating containing 1:1 ratio of silicon-substituted hydroxyapatite and silver-substituted hydroxyapatite as the top functional layer, and hydroxyapatite as the base layer, was produced via the drop-on-demand micro-dispensing technique, as a strategic approach in the fight against infection along with the promotion of bone tissue regeneration. The homogeneous distribution of silicon-substituted hydroxyapatite and silver-substituted hydroxyapatite micro-droplets at alternate position in silicon-substituted hydroxyapatite-silver-substituted hydroxyapatite/hydroxyapatite coating delayed the exponential growth of Staphylococcus aureus for up to 24 h, and gave rise to up-regulated expression of alkaline phosphatase activity, type I collagen and osteocalcin as compared to hydroxyapatite and silver-substituted hydroxyapatite coatings. Despite containing reduced amounts of silicon-substituted hydroxyapatite and silver-substituted hydroxyapatite micro-droplets over the coated area than silicon-substituted hydroxyapatite and silver-substituted hydroxyapatite coatings, silicon-substituted hydroxyapatite-silver-substituted hydroxyapatite/hydroxyapatite coating exhibited effective antibacterial property with enhanced bioactivity. By exhibiting good controllability of distributing silicon-substituted hydroxyapatite, silver-substituted hydroxyapatite and hydroxyapatite micro-droplets, it was demonstrated that drop-on-demand micro-dispensing technique was capable in harnessing the advantages of silver-substituted hydroxyapatite, silicon-substituted hydroxyapatite and hydroxyapatite to produce a multi-material coating along with enhanced bioactivity and reduced infection.

  13. Assessment of potential exposure to friable insulation materials containing asbestos

    NASA Technical Reports Server (NTRS)

    Kim, W. S.; Kuivinen, D. E.

    1980-01-01

    Asbestos and the procedures for assessing potential exposure hazards are discussed. Assessment includes testing a bulk sample of the suspected material for the presence of asbestos, and monitoring the air, if necessary. Based on field inspections and laboratory analyses, the health hazard is evaluated, and abatement measures are taken if a potential hazard exists. Throughout the assessment and abatement program, all applicable regulations are administered as specified by the Environmental Protection Agency and the Occupational Safety and Health Administration.

  14. A comparative study of the effects of different bioactive fillers in PLGA matrix composites and their suitability as bone substitute materials: A thermo-mechanical and in vitro investigation.

    PubMed

    Simpson, R L; Nazhat, S N; Blaker, J J; Bismarck, A; Hill, R; Boccaccini, A R; Hansen, U N; Amis, A A

    2015-10-01

    Bone substitute composite materials with poly(L-lactide-co-glycolide) (PLGA) matrices and four different bioactive fillers: CaCO3, hydroxyapatite (HA), 45S5 Bioglass(®) (45S5 BG), and ICIE4 bioactive glass (a lower sodium glass than 45S5 BG) were produced via melt blending, extrusion and moulding. The viscoelastic, mechanical and thermal properties, and the molecular weight of the matrix were measured. Thermogravimetric analysis evaluated the effect of filler composition on the thermal degradation of the matrix. Bioactive glasses caused premature degradation of the matrix during processing, whereas CaCO3 or HA did not. All composites, except those with 45S5 BG, had similar mechanical strength and were stiffer than PLGA alone in compression, whilst all had a lower tensile strength. Dynamic mechanical analysis demonstrated an increased storage modulus (E') in the composites (other than the 45S5 BG filled PLGA). The effect of water uptake and early degradation was investigated by short-term in vitro aging in simulated body fluid, which indicated enhanced water uptake over the neat polymer; bioactive glass had the greatest water uptake, causing matrix plasticization. These results enable a direct comparison between bioactive filler type in poly(α-hydroxyester) composites, and have implications when selecting a composite material for eventual application in bone substitution.

  15. Bioactive glasses as potential radioisotope vectors for in situ cancer therapy: investigating the structural effects of yttrium.

    PubMed

    Christie, Jamieson K; Malik, Jahangir; Tilocca, Antonio

    2011-10-21

    The incorporation of yttrium in bioactive glasses (BGs) could lead to a new generation of radionuclide vectors for cancer therapy, with high biocompatibility, controlled biodegradability and the ability to enhance the growth of new healthy tissues after the treatment with radionuclides. It is essential to assess whether and to what extent yttrium incorporation affects the favourable properties of the BG matrix: ideally, one would like to combine the high surface reactivity typical of BGs with a slow release of radioactive yttrium. Molecular Dynamics simulations show that, compared to a BG composition with the same silica fraction, incorporation of yttrium results in two opposing effects on the glass durability: a more fragmented silicate network (leading to lower durability) and a stronger yttrium-mediated association between separate silicate fragments (leading to higher durability). The simulations also highlight a high site-selectivity and some clustering of yttrium cations, which are likely linked to the observed slow rate of yttrium released from related Y-BG compositions. Optimisation of yttrium BG compositions for radiotherapy applications thus depends on the delicate balance between these effects.

  16. Bioactive compounds and nutritional significance of virgin argan oil--an edible oil with potential as a functional food.

    PubMed

    Cabrera-Vique, Carmen; Marfil, Rocío; Giménez, Rafael; Martínez-Augustin, Olga

    2012-05-01

    This review compiles recently published scientific reports on the bioactive compounds present in virgin argan oil along with their possible beneficial effects on human health, which could justify consideration of this oil as a new functional food. Virgin argan oil is characterized by high levels of linoleic and oleic acids, tocopherols (especially γ-tocopherol), and minor compounds such as sterols, carotenoids, and squalene. The total antioxidant capacity of virgin argan oil is higher than that of other vegetable oils. Recent studies suggest that this edible oil, as a functional food, may play a role in disease prevention. For example, some authors have found it to have hypolipidemic, hypocholesterolemic, hypoglycemic, and antihypertensive effects as well as a possible role in cancer prevention. This review demonstrates the need for further studies in order to fully characterize argan oil from bromatological, nutritional, culinary, and technological perspectives. In particular, the scarcity of clinical data hampers relevant conclusions from being drawn regarding the therapeutic effects of virgin argan oil. © 2012 International Life Sciences Institute.

  17. Inhibitory potential of Grifola frondosa bioactive fractions on α-amylase and α-glucosidase for management of hyperglycemia.

    PubMed

    Su, Chun-Han; Lu, Tzy-Ming; Lai, Min-Nan; Ng, Lean-Teik

    2013-01-01

    This study examined the inhibitory effects of Grifola frondosa (GF), a medicinal mushroom popularly consumed in traditional medicine and health food, on digestive enzymes related to type 2 diabetes; chemical profiles and inhibitory kinetics of its bioactive fractions were also analyzed. Results showed that all GF extracts showed weak anti-α-amylase activity; however, strong anti-α-glucosidase activity was noted on GF n-hexane extract (GF-H). Further fractionation confirmed that compared with acarbose (a commercial α-glucosidase inhibitor), the nonpolar fraction of GF possessed a stronger anti-α-glucosidase activity but a weaker anti-α-amylase activity. These activities were not derived from ergosterol and ergosterol peroxide, two major compounds of this fraction. The inhibitory kinetics of GF-H on α-glucosidase was competitive inhibition. GF-H was as good as acarbose in inhibiting the starch digestion in vitro. Oleic acid and linoleic acid could be the major active constituents that have contributed to the potency of GF in inhibiting α-glucosidase activity.

  18. Evaluation of the shedding potential of textile materials.

    PubMed

    De Wael, K; Lepot, L; Lunstroot, K; Gason, F

    2010-12-01

    A practical method is proposed to assess the shedding potential of textile materials. The evaluation of the sheddability is based on the use of adhesive tapes and on comparison, using three different sheddability scales for cotton, wool and fine man-made fibres.

  19. CLASSIFICATION OF MATERIALS AS POTENTIAL SOURCES OF INDOOR AIR POLLUTION

    EPA Science Inventory

    The report gives a complete classification of all materials used in the construction of, or brought inside, homes and office buildings. n the classification tables Presented in the report, shaded entries are potential Sources of indoor air emissions. he classification system is b...

  20. Potential SSP Perfluorooctanoic Acid Related Fluoropolymer Materials Obsolescence

    NASA Technical Reports Server (NTRS)

    Segars, Matt G.

    2006-01-01

    The Shuttle Environmental Assurance Initiative (SEA) has identified a potential for the Space Shuttle Program (SSP) to incur materials obsolescence issues due to agreements between the fluoro-chemical industry and the United States Environmental Protection Agency (USEPA) to participate in a Global Stewardship Program for perfluorooctanoic acid (PFOA). This presentation will include discussions of the chemistry, regulatory drivers, affected types of fluoropolymer and fluoroelastomer products, timeline for reformulations, and methodology for addressing the issue. It will cover the coordination of assessment efforts with the International Space Station and Head Quarters Air Force Space Command, along with some examples of impacted materials. The presentation is directed at all members of the international aerospace community concerned with identifying potential environmentally driven materials obsolescence issues.

  1. Applications of the potential microprobe to electronic ceramic materials

    SciTech Connect

    Schubert, W.K.

    1988-01-01

    The potential microprobe consists of a fine tipped tungsten needle mounted on a computer controlled, three axis mechanical/piezo positioner. The probe is mounted to the stage of a standard scanning electron microscope, and allows one to make electrical potential measurements on a very fine spatial scale (greater than or equal to 10 nm). The potential microprobe and its operation are discussed. Applications of the technique to polycrystalline silicon, ceramic superconductors, and ZnO varistor materials are presented. 19 refs., 4 figs.

  2. Prophylactic bioactive screw fixation as an alternative augmentation for femoroplasty.

    PubMed

    Hananouchi, Takehito

    2015-04-01

    Femoroplasty is theoretically a prophylactic surgical procedure for femoral neck fracture. Although bone cement is generally used for augmentation, its distribution cannot be easily controlled. This study investigated whether a bioactive screw is feasible for femoroplasty as an alternative augmentation material. A mechanical test was done to compare the strength of four types of augmentation bioactive screw (Superfixsorb), two bioinert cements, or no intervention in a composite femoral bone. The peak load to fracture under simulated falling was compared among the four groups. The mean peak load to failure in the bioactive screw group (2667 N) was significantly higher than that in the intact group (2391 N) (p=0.028), comparable to that in the Simplex P cement group (2864 N) (p=0.11), and significantly lower than that of the cranioplastic cement group (3022 N) (p=0.006). The strength of a composite femur with the bioactive screw was higher than that of an intact bone and comparable to one cement augmentation. Thus, this bioactive screw can be potentially used as augmentation material for femoroplasty.

  3. Bioactive potential of Vitis labrusca L. grape juices from the Southern Region of Brazil: phenolic and elemental composition and effect on lipid peroxidation in healthy subjects.

    PubMed

    Toaldo, Isabela Maia; Cruz, Fernanda Alves; Alves, Tatiana de Lima; de Gois, Jefferson Santos; Borges, Daniel L G; Cunha, Heloisa Pamplona; da Silva, Edson Luiz; Bordignon-Luiz, Marilde T

    2015-04-15

    Grapes are rich in polyphenols with biologically active properties. Although the bioactive potential of grape constituents are frequently reported, the effects of Brazilian Vitis labrusca L. grape juices ingestion have not been demonstrated in humans. This study identified the phenolic and elemental composition of red and white grape juices and the effect of organic and conventional red grape juice consumption on lipid peroxidation in healthy individuals. Concentrations of anthocyanins, flavanols and phenolic acids and the in vitro antioxidant activity were significantly higher in the organic juice. The macro-elements K, Ca, Na and Mg were the most abundant minerals in all juices. The acute consumption of red grape juices promoted significant decrease of lipid peroxides in serum and TBARS levels in plasma. It is concluded that red V. labrusca L. grape juices produced in Southern Brazil showed lipid peroxidation inhibition abilities in healthy subjects, regardless of the cultivation system. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Antimicrobial effectiveness of bioactive packaging materials from edible chitosan and casein polymers: assessment on carrot, cheese, and salami.

    PubMed

    Moreira, Maria del Rosario; Pereda, Mariana; Marcovich, Norma E; Roura, Sara I

    2011-01-01

    Antimicrobial packaging is one of the most promising active packaging systems for controlling spoilage and pathogenic microorganisms. In this work, the intrinsic antimicrobial properties of chitosan (CH) were combined with the excellent thermoplastic and film-forming properties of sodium caseinate (SC) to prepare SC/CH film-forming solutions and films. The antimicrobial effectiveness of SC, CH, and SC/CH coatings on the native microfloras of cheese, salami, and carrots was evaluated. In vitro assays through the test tube assay indicated that the most significant antimicrobial effect was achieved by CH and SC/CH solutions on carrot and cheese native microfloras. SC film-forming solutions did not exert antimicrobial activity on any of the native microflora studied. SC, CH, and SC/CH films stored in controlled environments showed that the retention of the antimicrobial action was observed until 5-d storage, at 65% relative humidity in both temperatures (10 °C and 20 °C). In vivo assays were also performed with SC, CH, and SC/CH applied as coatings or wrappers on the 3 food substrates. CH and SC/CH applied at both immersion and wrapper exerted a significant bactericidal action on mesophilic, psychrotrophic, and yeasts and molds counts, showing the 3 microbial populations analyzed a significant reduction (2.0 to 4.5 log CFU/g). An improvement of the bactericidal properties of the CH/SC blend respect to those of the neat CH film is reported. The ionic interaction between both macromolecules enhances its antimicrobial properties. Practical Application: The continuous consumer interest in high quality and food safety, combined with environmental concerns has stimulated the development and study of biodegradable coatings that avoid the use of synthetic materials. Among them, edible coatings, obtained from generally recognized as safe (GRAS) materials, have the potential to reduce weight loss, respiration rate, and improve food appearance and integrity. They can be used in

  5. Development of bioactive peptides from fish proteins and their health promoting ability.

    PubMed

    Senevirathne, Mahinda; Kim, Se-Kwon

    2012-01-01

    Great amount of marine fish species have been identified with potential nutraceutical and medicinal values. Consequently, a number of bioactive compounds have been identified including fish muscle proteins, peptides, collagen and gelatin, fish oil, fish bone. Bioactive peptides derived from various fish muscle proteins have shown various biological activities including antihypertensive, antibacterial, anticoagulant, anti-inflammatory, and antioxidant activities, and hence they may be a potential material for biomedical and food industries. Further, they are commonly used in medical and pharmaceutical industries as carrier molecules for drugs, proteins, and genes. Hence, fish muscle protein-derived peptides are valuable natural resources that can be potential material for biomedical, nutraceutical, and food industries.

  6. Reversed-phase high-performance Liquid Chromatography-ultraviolet Photodiode Array Detector Validated Simultaneous Quantification of six Bioactive Phenolic Acids in Roscoea purpurea Tubers and their In vitro Cytotoxic Potential against Various Cell Lines

    PubMed Central

    Srivastava, Sharad; Misra, Ankita; Kumar, Dharmesh; Srivastava, Amit; Sood, Anil; Rawat, AKS

    2015-01-01

    Background: Roscoea purpurea or Roscoea procera Wall. (Zingiberaceae) is traditionally used for nutrition and in the treatment of various ailments. Objective: Simultaneous reversed-phase high-performance liquid chromatography-ultraviolet (RP-HPLC) photodiode array detector identification of phenolic acids (PA's) was carried out in whole extract of tuber and their cytotoxic potential was estimated along with radical scavenging action. Bioactivity guided fractionation was also done to check the response potential against the same assay. Materials and Methods: Identification and method validation was performed on RP-HPLC column and in vitro assays were used for bioactivity. Results: Protocatechuic acid, syringic acid, ferulic acid, rutin, apigenin, and kaempferol were quantified as 0.774%, 0.064%, 0.265%, 1.125%, 0.128%, and 0.528%, respectively. Validated method for simultaneous determination of PA's was found to be accurate, reproducible, and linearity was observed between peak area response and concentration. Recovery of identified PA's was within the acceptable limit of 97.40–104.05%. Significant pharmacological response was observed in whole extract against in vitro cytotoxic assay, that is, Sulforhodamine B assay, however, fractionation results in decreased action potential. Similar pattern of results were observed in the antioxidant assay, as total phenolic content and total flavonoid content were highest in whole extract and decreases with fractionation. Radical scavenging activity was prominent in chloroform fraction, exhibiting IC50 at 0.25 mg/mL. Conclusion: Study, thus, reveals that R. purpurea exhibit significant efficacy in cytotoxic activity with the potentiality of scavenging free radicals due the presence of PA's as reported through RP-HPLC. SUMMARY Proto-catechuic acid, syringic acid, ferulic acid, rutin, apigenin and kaempferol were quantified as 0.774, 0.064, 0.265, 1.125, 0.128 and 0.528 %Preliminary cytotoxic activity revealed that whole

  7. Mechanics, degradability, bioactivity, in vitro, and in vivo biocompatibility evaluation of poly(amino acid)/hydroxyapatite/calcium sulfate composite for potential load-bearing bone repair.

    PubMed

    Fan, Xiaoxia; Ren, Haohao; Luo, Xiaoman; Wang, Peng; Lv, Guoyu; Yuan, Huipin; Li, Hong; Yan, Yonggang

    2016-03-01

    A ternary composite of poly(amino acid), hydroxyapatite, and calcium sulfate (PAA/HA/CS) was prepared using in situ melting polycondensation method and evaluated in terms of mechanical strengths, in vitro degradability, bioactivity, as well as in vitro and in vivo biocompatibility. The results showed that the ternary composite exhibited a compressive strength of 147 MPa, a bending strength of 121 MPa, a tensile strength of 122 MPa, and a tensile modulus of 4.6 GPa. After immersion in simulated body fluid, the compressive strength of the composite decreased from 147 to 98 MPa for six weeks and the bending strength decreased from 121 to 75 MPa for eight weeks, and both of them kept stable in the following soaking period. The composite could be slowly degraded with 7.27 wt% loss of initial weight after soaking in phosphate buffered solution for three weeks when started to keep stable weight in the following days. The composite was soaked in simulated body fluid solution and the hydroxyapatite layer, as flower-like granules, formed on the surface of the composite samples, showing good bioactivity. Moreover, it was found that the composite could promote proliferation of MG-63 cells, and the cells with normal phenotype extended and spread well on the composite surface. The implantation of the composite into the ulna of sheep confirmed that the composite was biocompatible and osteoconductive in vivo, and offered the PAA/HA/CS composite promising material for load-bearing bone substitutes for clinical application. © The Author(s) 2015.

  8. New perspectives on potential hydrogen storage materials using high pressure.

    PubMed

    Song, Yang

    2013-09-21

    In addressing the global demand for clean and renewable energy, hydrogen stands out as the most suitable candidate for many fuel applications that require practical and efficient storage of hydrogen. Supplementary to the traditional hydrogen storage methods and materials, the high-pressure technique has emerged as a novel and unique approach to developing new potential hydrogen storage materials. Static compression of materials may result in significant changes in the structures, properties and performance that are important for hydrogen storage applications, and often lead to the formation of unprecedented phases or complexes that have profound implications for hydrogen storage. In this perspective article, 22 types of representative potential hydrogen storage materials that belong to four major classes--simple hydride, complex hydride, chemical hydride and hydrogen containing materials--were reviewed. In particular, their structures, stabilities, and pressure-induced transformations, which were reported in recent experimental works together with supporting theoretical studies, were provided. The important contextual aspects pertinent to hydrogen storage associated with novel structures and transitions were discussed. Finally, the summary of the recent advances reviewed and the insight into the future research in this direction were given.

  9. Estimating potential genotoxicity for direct coal-liquefaction materials

    SciTech Connect

    Wilson, B.W.; Pelroy, R.A.; Renne, R.A.

    1981-05-01

    Fuels derived from coal liquefaction processes are chemically complex, highly aromatic mixtures, the specific constituency of which is fairly process-dependent. Genotoxicity, when found in these materials, is generally confined to the heavy-end fractions or full boiling range materials which contain heavy ends. The moderately polar or nitrogen base fractions of these heavy-end materials are generally the most mutagenically active. In some SRC-II heavy-end bottoms and the SRC-I solid product, however, the highly polar fractions contribute substantially to the mutagenicity. Specific compounds presently recognized as contributors or potential contributors to genotoxicity of the coal liquids studied include polycyclic primary aromatic amines, and to a much lesser extent, polycyclic aromatic hydrocarbons having four or more rings, certain polycyclic nitrogen heterocycles as well as certain polycyclic sulfur heterocyclics. The degree to which a given material has been subjected to reducing conditions during production appears to be an important parameter in determining its potential genotoxicity, the more severely reduced materials tending to be less genotoxic.

  10. Transfersomes: self-optimizing carriers for bioactives.

    PubMed

    Rai, Kavita; Gupta, Yashwant; Jain, Anekant; Jain, Sanjay K

    2008-01-01

    The transdermal route of drug delivery has gained great interest of pharmaceutical research, as it circumvents number of problems associated with oral route of drug administration. The major barrier in transdermal delivery of drug is the skin intrinsic barrier, the stratum corneum, the outermost envelop of the skin that offers the principal hurdle for diffusion of hydrophilic ionizable bioactives. Recently, various strategies have been used to augment the transdermal delivery of bioactives. Mainly, they include iontophoresis, electrophoresis, sonophoresis, chemical permeation enhancers, microneedles, and vesicular system (liposomes, niosomes, elastic liposomes such as ethosomes and transfersomes). Among these strategies transferosomes appear promising. Transport of this vesicular system through skin and epithelial hurdle depends upon the flexibility of their membrane, which can be attained using appropriate ratio of surfactant. Transfersomes have shown immense potential in drug delivery across the skin. Recent success also demonstrates the potential of transfersome in vaccine, steroid, protein, and peptide delivery across the skin. It is also used for transporting genetic material and achieving transfection. This review highlights the various aspects of the transferosomes in the effective delivery of drug/bioactives across the skin.

  11. The Bioactivity and Photocatalytic Properties of Titania Nanotube Coatings Produced with the Use of the Low-Potential Anodization of Ti6Al4V Alloy Surface

    PubMed Central

    Radtke, Aleksandra; Kozak, Wiesław; Sadowska, Beata; Więckowska-Szakiel, Marzena; Szubka, Magdalena; Talik, Ewa; Pleth Nielsen, Lars; Piszczek, Piotr

    2017-01-01

    Titania nanotube (TNT) coatings were produced using low-potential anodic oxidation of Ti6Al4V substrates in the potential range 3–20 V. They were analysed by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The wettability was estimated by measuring the contact angle when applying water droplets. The bioactivity of the TNT coatings was established on the basis of the biointegration assay (L929 murine fibroblasts adhesion and proliferation) and antibacterial tests against Staphylococcus aureus (ATCC 29213). The photocatalytic efficiency of the TNT films was studied by the degradation of methylene blue under UV irradiation. Among the studied coatings, the TiO2 nanotubes obtained with the use of 5 V potential (TNT5) were found to be the most appropriate for medical applications. The TNT5 sample possessed antibiofilm properties without enriching it by additional antimicrobial agent. Furthermore, it was characterized by optimal biocompatibility, performing better than pure Ti6Al4V alloy. Moreover, the same sample was the most photocatalytically active and exhibited the potential for the sterilization of implants with the use of UV light and for other environmental applications. PMID:28933732

  12. Dietary plant bioactives for poultry health and productivity.

    PubMed

    Wallace, R J; Oleszek, W; Franz, C; Hahn, I; Baser, K H C; Mathe, A; Teichmann, K

    2010-08-01

    1. Plants and their biologically active chemical constituents, sometimes called secondary metabolites or bioactives, present numerous opportunities for the improvement of livestock production by inclusion in the diet. 2. Many such plant derived materials have well established therapeutic values in man; however, their potential as feed additives in animal production, particularly of poultry, remains largely unexploited. 3. There is increasing evidence indicating that they can be efficient in controlling diseases, and plant bioactives may also influence production parameters such as feed efficiency and product quality. 4. It has been reported that they may even replicate some of the effects of antibiotic growth promoters, which were banned from use in Europe from 2006. 5. This review assesses the status of plant bioactives in poultry production and their mode of action on avian physiology, particularly in the digestive tract.

  13. BIOACTIVE PROTEINS, PEPTIDES, AND AMINO ACIDS FROM MACROALGAE(1).

    PubMed

    Harnedy, Pádraigín A; FitzGerald, Richard J

    2011-04-01

    Macroalgae are a diverse group of marine organisms that have developed complex and unique metabolic pathways to ensure survival in highly competitive marine environments. As a result, these organisms have been targeted for mining of natural biologically active components. The exploration of marine organisms has revealed numerous bioactive compounds that are proteinaceous in nature. These include proteins, linear peptides, cyclic peptides and depsipeptides, peptide derivatives, amino acids, and amino acid-like components. Furthermore, some species of macroalgae have been shown to contain significant levels of protein. While some protein-derived bioactive peptides have been characterized from macroalgae, macroalgal proteins currently still represent good candidate raw materials for biofunctional peptide mining. This review will provide an overview of the important bioactive amino-acid-containing compounds that have been identified in macroalgae. Moreover, the potential of macroalgal proteins as substrates for the generation of biofunctional peptides for utilization as functional foods to provide specific health benefits will be discussed.

  14. Investigation of woven composites as potential cryogenic tank materials

    NASA Astrophysics Data System (ADS)

    Islam, Md. S.; Melendez-Soto, E.; Castellanos, A. G.; Prabhakar, P.

    2015-12-01

    In this paper, carbon fiber and Kevlar® fiber woven composites were investigated as potential cryogenic tank materials for storing liquid fuel in spacecraft or rocket. Towards that end, both carbon and Kevlar® fiber composites were manufactured and tested with and without cryogenic exposure. The focus was on the investigation of the influence of initial cryogenic exposure on the degradation of the composite. Tensile, flexural and inter laminar shear strength (ILSS) tests were conducted, which indicate that Kevlar® and carbon textile composites are potential candidates for use under cryogenic exposure.

  15. Status and potential of atmospheric plasma processing of materials

    SciTech Connect

    Pappas, Daphne

    2011-03-15

    This paper is a review of the current status and potential of atmospheric plasma technology for materials processing. The main focus is the recent developments in the area of dielectric barrier discharges with emphasis in the functionalization of polymers, deposition of organic and inorganic coatings, and plasma processing of biomaterials. A brief overview of both the equipment being used and the physicochemical reactions occurring in the gas phase is also presented. Atmospheric plasma technology offers major industrial, economic, and environmental advantages over other conventional processing methods. At the same time there is also tremendous potential for future research and applications involving both the industrial and academic world.

  16. A potential base substrate for deformable scintillation materials

    NASA Astrophysics Data System (ADS)

    Nakamura, Hidehito; Sato, Nobuhiro; Kitamura, Hisashi; Shirakawa, Yoshiyuki; Takahashi, Sentaro

    2016-05-01

    Deformable scintillation materials for radiation detection are an original concept that will impact many applications. Here we reveal the optical characteristics of readily available, transparent grease that consists of adhesive aromatic ring polymers. The aromatic ring polymer is methyl phenyl polysiloxane, commonly used in cosmetics, lubrication, heat conduction, and mechanical damping. It has a 285-nm excitation maximum and emits short wavelength light that peaks at 315 nm. The stopping power for 1 MeV electrons is 1.78 MeV cm2/g. The light-yield distribution has distinct peaks at 976 keV from internal conversion electrons and at 5486 keV from alpha particles. In addition, this particular methyl phenyl polysiloxane is safe for use and disposal, which is an excellent advantage. These aromatic ring polymers are potential base substrates for deformable scintillation materials and make an important addition to the categories of scintillation materials.

  17. Discolouration potential of endodontic procedures and materials: a review.

    PubMed

    Ahmed, H M A; Abbott, P V

    2012-10-01

    Advances in endodontic materials and techniques are at the forefront of endodontic research. Despite continuous improvements, tooth discolouration, especially in anterior teeth, is considered an undesirable consequence following endodontic treatment as it creates a range of aesthetic problems. This article aims to discuss the intrinsic and internalized tooth discolouration caused by endodontic procedures, and to address the discolouration potential of materials used during root canal treatment, including root canal irrigants, intra-canal medicaments, endodontic and post-endodontic filling materials. In addition, the discolouration patterns caused by combined endodontic and nonendodontic aetiological factors are discussed. The recommended guidelines that should be followed by dental practitioners to prevent and manage tooth discolouration are also outlined. © 2012 International Endodontic Journal.

  18. Drying of porous materials in a medium with variable potentials

    SciTech Connect

    Liu, J.Y. )

    1991-08-01

    This paper presents an application of the Luikov system of heat and mass transfer equations in dimensionless form to predict the temperature and moisture distributions in a slab of capillary-porous material during drying. The heat and mass potentials of the external medium in the boundary conditions are assumed to vary linearly with time. The method of solution is illustrated by considering the drying of a slab of lumber. Numerical results based on the estimated thermophysical properties of spruce are presented.

  19. Bioactivity of Rosmarinus officinalis essential oils against Apis mellifera, Varroa destructor and Paenibacillus larvae related to the drying treatment of the plant material.

    PubMed

    Maggi, M; Gende, L; Russo, K; Fritz, R; Eguaras, M

    2011-02-01

    In this study, chemical composition, physicochemical properties and bioactivity of two essential oils of Rosmarinus officinalis extracted from plant material with different drying treatments against Apis mellifera, Varroa destructor and Paenibacillus larvae were assessed. The lethal concentration 50 (LC50) for mites and bees was estimated using a complete exposure method test. The broth microdilution method was followed in order to determine the minimum inhibitory concentrations (MICs) of the essential oils against P. larvae. Physicochemical properties were similar in both the essential oils, but the percentage of components showed certain differences according to their drying treatment. β-Myrcene and 1,8-cineole were the main constituents in the oils. The LC50 for complete exposure method at 24, 48 and 72 h was minor for mites exposed to R. officinalis essential oil dried in oven conditions. MIC values were 700-800 µg mL(-1) and 1200 µg mL(-1) for R. officinalis dried in air and oven conditions, respectively. The results reported in this research show that oil toxicity against V. destructor and P. larvae differed depending on the drying treatment of the plant material before the distillation of essential oil.

  20. In vitro drug permeation enhancement potential of aloe gel materials.

    PubMed

    Lebitsa, Tebogo; Viljoen, Alvaro; Lu, Zhilei; Hamman, Josias

    2012-05-01

    Aloe vera gel previously showed the ability to increase the bioavailability of vitamins and to enhance the in vitro transport of a macromolecular drug across intestinal epithelial cell monolayers. The purpose of this study is to investigate the potential of other species of aloe to act as drug absorption enhancement agents. The effect of gel materials from three South African aloes; Aloe ferox, A. marlothii and A. speciosa on the transepithelial electrical resistance and permeability of atenolol across excised intestinal tissue of the rat as well as the transport of FITC-dextran across Caco-2 cell monolayers was investigated. The aloe gel materials exhibited the ability to statistically significantly reduce the transepithelial electrical resistance of excised rat intestinal tissue but did not significantly increase the transport of atenolol across this in vitro tissue model at the concentrations tested. At least one concentration of each aloe gel material enhanced the transport of FITC-dextran statistically significantly across Caco-2 cell monolayers. The aloe gel materials showed potential to act as drug absorption enhancing agents across intestinal epithelia. The absorption enhancement effect was dependent on the type of in vitro model and type of drug was investigated.

  1. Nanocellulose-based composites and bioactive agents for food packaging.

    PubMed

    Khan, Avik; Huq, Tanzina; Khan, Ruhul A; Riedl, Bernard; Lacroix, Monique

    2014-01-01

    Global environmental concern, regarding the use of petroleum-based packaging materials, is encouraging researchers and industries in the search for packaging materials from natural biopolymers. Bioactive packaging is gaining more and more interest not only due to its environment friendly nature but also due to its potential to improve food quality and safety during packaging. Some of the shortcomings of biopolymers, such as weak mechanical and barrier properties can be significantly enhanced by the use of nanomaterials such as nanocellulose (NC). The use of NC can extend the food shelf life and can also improve the food quality as they can serve as carriers of some active substances, such as antioxidants and antimicrobials. The NC fiber-based composites have great potential in the preparation of cheap, lightweight, and very strong nanocomposites for food packaging. This review highlights the potential use and application of NC fiber-based nanocomposites and also the incorporation of bioactive agents in food packaging.

  2. In-vitro evaluation of bioactive compounds, anti-oxidant, lipid peroxidation and lipoxygenase inhibitory potential of Citrus karna L. peel extract.

    PubMed

    Singh, Jagdeep; Sood, Shailja; Muthuraman, Arunachalam

    2014-01-01

    Many medicinal plants have been studied for their antioxidant and their pharmacological activity. Citrus species were well documented as potential antioxidant based therapy for cancer, inflammation, heart disease. Citrus seeds and peels have been shown to possess high antioxidant activity. Therefore, the present study to explore the antioxidant and lipid peroxidation & lipoxygenase inhibitory action of Citrus karna peel extracts were undertaken. Extraction was performed with different solvents of increasing polarity and yield was calculated. Peel extracts were also analyzed for the presence of phenols, flavonoids, vitamin C, and carotenoids. Then the Citrus karna peel extracts were evaluated for the antioxidant and lipid peroxidation & lipoxygenase inhibitory action In-Vitro. In further, the quantification of hesperidin and naringin was carried out by HPLC-DAD method. The results indicated the presence of phenols, flavonoids, vitamin C, carotenoids, hesperidin and naringin in Citrus karna peel extracts with maximum yield of (3.91% w/w). Citrus karna peel extracts were also found to have potential antioxidant and lipid peroxidation & lipoxygenase inhibitory action. Therefore, Citrus karna peel extracts could be used for the future therapeutic medicine due to presence of potential bioactive compounds.

  3. Bioactive Glasses: Frontiers and Challenges

    PubMed Central

    Hench, Larry L.; Jones, Julian R.

    2015-01-01

    Bioactive glasses were discovered in 1969 and provided for the first time an alternative to nearly inert implant materials. Bioglass formed a rapid, strong, and stable bond with host tissues. This article examines the frontiers of research crossed to achieve clinical use of bioactive glasses and glass–ceramics. In the 1980s, it was discovered that bioactive glasses could be used in particulate form to stimulate osteogenesis, which thereby led to the concept of regeneration of tissues. Later, it was discovered that the dissolution ions from the glasses behaved like growth factors, providing signals to the cells. This article summarizes the frontiers of knowledge crossed during four eras of development of bioactive glasses that have led from concept of bioactivity to widespread clinical and commercial use, with emphasis on the first composition, 45S5 Bioglass®. The four eras are (a) discovery, (b) clinical application, (c) tissue regeneration, and (d) innovation. Questions still to be answered for the fourth era are included to stimulate innovation in the field and exploration of new frontiers that can be the basis for a general theory of bioactive stimulation of regeneration of tissues and application to numerous clinical needs. PMID:26649290

  4. Bioactive Glasses: Frontiers and Challenges.

    PubMed

    Hench, Larry L; Jones, Julian R

    2015-01-01

    Bioactive glasses were discovered in 1969 and provided for the first time an alternative to nearly inert implant materials. Bioglass formed a rapid, strong, and stable bond with host tissues. This article examines the frontiers of research crossed to achieve clinical use of bioactive glasses and glass-ceramics. In the 1980s, it was discovered that bioactive glasses could be used in particulate form to stimulate osteogenesis, which thereby led to the concept of regeneration of tissues. Later, it was discovered that the dissolution ions from the glasses behaved like growth factors, providing signals to the cells. This article summarizes the frontiers of knowledge crossed during four eras of development of bioactive glasses that have led from concept of bioactivity to widespread clinical and commercial use, with emphasis on the first composition, 45S5 Bioglass(®). The four eras are (a) discovery, (b) clinical application, (c) tissue regeneration, and (d) innovation. Questions still to be answered for the fourth era are included to stimulate innovation in the field and exploration of new frontiers that can be the basis for a general theory of bioactive stimulation of regeneration of tissues and application to numerous clinical needs.

  5. Plasma pharmacochemistry combined with pharmacokinetics and pattern recognition analysis to screen potentially bioactive components from Daming capsule using ultra high performance liquid chromatography with electrospray ionization quadrupole time-of-flight mass spectrometry.

    PubMed

    An, Ran; Li, Yamei; Li, Mu; Bai, Yan; Lu, Yanjie; Du, Zhimin

    2015-05-01

    Daming capsule is a traditional Chinese medicine for hyperlipidemia treatment. However, the vague understanding of the bioactive components of Daming capsule hampers its modernization and internationalization. This work first developed a high-throughput, high-resolution, and high-sensitivity ultra high performance liquid chromatography with electrospray ionization quadrupole time-of-flight tandem mass spectrometry method for identifying the absorbed compounds and monitoring the pharmacokinetics of Daming capsule. A high-throughput strategy integrating plasma pharmacochemistry, pharmacokinetics, and pattern recognition analysis was also established for screening the bioactive components of Daming capsule in vivo. The established strategy based on ultra high performance liquid chromatography with electrospray ionization quadrupole time-of-flight tandem mass spectrometry was successfully applied to screen the bioactive components of Daming capsule. Up to 53 absorbed compounds were identified. Six anthraquinones with fast and high absorption, namely, emodin-O-glucoside, aurantio-obtusin, aloe-emodin, rhein, emodin, and chrysophanol, were screened as potentially bioactive components of Daming capsule. The plasma pharmacochemistry and pharmacokinetics of Daming capsule were reported for the first time. Notably, the high-throughput and reliable strategy facilitated the screening and identification of bioactive components of traditional Chinese medicine, thereby providing novel insights into the research and development of new drugs.

  6. (Metallo)porphyrins for potential materials science applications.

    PubMed

    Smykalla, Lars; Mende, Carola; Fronk, Michael; Siles, Pablo F; Hietschold, Michael; Salvan, Georgeta; Zahn, Dietrich R T; Schmidt, Oliver G; Rüffer, Tobias; Lang, Heinrich

    2017-01-01

    The bottom-up approach to replace existing devices by molecular-based systems is a subject that attracts permanently increasing interest. Molecular-based devices offer not only to miniaturize the device further, but also to benefit from advanced functionalities of deposited molecules. Furthermore, the molecules itself can be tailored to allow via their self-assembly the potential fabrication of devices with an application potential, which is still unforeseeable at this time. Herein, we review efforts to use discrete (metallo)porphyrins for the formation of (sub)monolayers by surface-confined polymerization, of monolayers formed by supramolecular recognition and of thin films formed by sublimation techniques. Selected physical properties of these systems are reported as well. The application potential of those ensembles of (metallo)porphyrins in materials science is discussed.

  7. (Metallo)porphyrins for potential materials science applications

    PubMed Central

    Smykalla, Lars; Mende, Carola; Fronk, Michael; Siles, Pablo F; Hietschold, Michael; Salvan, Georgeta; Zahn, Dietrich R T; Schmidt, Oliver G

    2017-01-01

    The bottom-up approach to replace existing devices by molecular-based systems is a subject that attracts permanently increasing interest. Molecular-based devices offer not only to miniaturize the device further, but also to benefit from advanced functionalities of deposited molecules. Furthermore, the molecules itself can be tailored to allow via their self-assembly the potential fabrication of devices with an application potential, which is still unforeseeable at this time. Herein, we review efforts to use discrete (metallo)porphyrins for the formation of (sub)monolayers by surface-confined polymerization, of monolayers formed by supramolecular recognition and of thin films formed by sublimation techniques. Selected physical properties of these systems are reported as well. The application potential of those ensembles of (metallo)porphyrins in materials science is discussed. PMID:28904840

  8. Potentials and policy implications of energy and material efficiency improvement

    SciTech Connect

    Worrell, Ernst; Levine, Mark; Price, Lynn; Martin, Nathan; van den Broek, Richard; Block, Kornelis

    1997-01-01

    There is a growing awareness of the serious problems associated with the provision of sufficient energy to meet human needs and to fuel economic growth world-wide. This has pointed to the need for energy and material efficiency, which would reduce air, water and thermal pollution, as well as waste production. Increasing energy and material efficiency also have the benefits of increased employment, improved balance of imports and exports, increased security of energy supply, and adopting environmentally advantageous energy supply. A large potential exists for energy savings through energy and material efficiency improvements. Technologies are not now, nor will they be, in the foreseeable future, the limiting factors with regard to continuing energy efficiency improvements. There are serious barriers to energy efficiency improvement, including unwillingness to invest, lack of available and accessible information, economic disincentives and organizational barriers. A wide range of policy instruments, as well as innovative approaches have been tried in some countries in order to achieve the desired energy efficiency approaches. These include: regulation and guidelines; economic instruments and incentives; voluntary agreements and actions, information, education and training; and research, development and demonstration. An area that requires particular attention is that of improved international co-operation to develop policy instruments and technologies to meet the needs of developing countries. Material efficiency has not received the attention that it deserves. Consequently, there is a dearth of data on the qualities and quantities for final consumption, thus, making it difficult to formulate policies. Available data, however, suggest that there is a large potential for improved use of many materials in industrialized countries.

  9. Potential inert matrix materials: Materials synthesis and evaluation of in-service engineering parameters

    NASA Astrophysics Data System (ADS)

    Xu, Peng

    Containing no fertile materials, inert matrix fuel (IMF) has been introduced as a potential transmutation solution for the increasing inventory of both weapon grade and reactor grade plutonium (Pu). In the present work, the MgO-pyrochlore (Nd2Zr2O7) composites and spinel magnesium stannate (Mg2SnO4) were selected as potential inert matrix (IM) materials. A comprehensive investigation was conducted on evaluation of the engineering parameters of the potential IM materials. The MgO-Nd2Zr2O7 composites and Mg 2SnO4 were fabricated through conventional solid state processing. The crystal structure and microstructure of the synthesized composites and Mg2SnO4 were studied. The irradiation tolerance of the potential IM materials was first assessed. The resistance of Mg2SnO 4 against irradiation induced amorphization was assessed experimentally using in situ TEM technique. The critical amorphization doses for Mg2SnO4 irradiated by 1 MeV Kr2+ ions were determined to be 5.5 dpa at 50 K and 11.0 dpa at 150 K, respectively. The obtained results were compared with other spinels especially MgAl 2O4, and the radiation tolerance of spinels were discussed. The next evaluation was water corrosion resistance of the potential IM materials. Homogeneous MgO-Nd2Zr2O7 composites exhibited an improved hydrothermal corrosion resistance than inhomogeneous composites and pure MgO. Even though spinel Mg2SnO4 was not stable in water at 300°C and saturation pressure, the corrosion was limited only to the surface, and the volume and mass changes were less than 1 % after 720 h corrosion. Feasibility of aqueous reprocessing was evaluated by studying the dissolution behavior of the potential IM materials in acidic solutions, with an emphasis on nitric acid. Dissolution of the MgO-Nd2Zr2O 7 composites in HNO3 resulted in a selective dissolution of MgO. Mechanical agitation such as magnetic bar stirring was necessary to achieve a completed dissolution of MgO and disintegration of porous Nd 2Zr2O7

  10. Evaluation of antioxidant potential, enzyme inhibition activity and phenolic profile of Lathyrus cicera and Lathyrus digitatus: Potential sources of bioactive compounds for the food industry.

    PubMed

    Llorent-Martínez, E J; Ortega-Barrales, P; Zengin, G; Mocan, A; Simirgiotis, M J; Ceylan, R; Uysal, S; Aktumsek, A

    2017-09-01

    The genus Lathyrus has great importance in terms of food and agricultural areas. In this study, the in vitro antioxidant activity (phosphomolybdenum, DPPH, ABTS, FRAP, CUPRAC and metal chelating) and enzyme inhibitory activity evaluation (acetylcholinesterase, butyrylcholinesterase, α-amylase and α-glucosidase) of L. cicera and L. digitatus were investigated, as well as their phytochemical profiles. The screening of the main phytochemical compounds in aerial parts of L. cicera and L. digitatus was carried out by high-performance liquid chromatography with electrospray ionization mass spectrometric detection (HPLC-ESI-MS(n)), observing that flavonoids represent the highest percentage of identified compounds, with abundance of tri- and tetra-glycosilated flavonoids, including acylated ones, especially in L. cicera. Generally, L. digitatus exhibited stronger antioxidant and enzyme inhibitory activities in correlation with its higher level of phenolics. The high number of phenolic compounds and the results of the antioxidant and enzyme assays suggest that these plants may be further used as sources of bioactive compounds, and for the preparation of new nutraceuticals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Photon absorption potential coefficient as a tool for materials engineering

    NASA Astrophysics Data System (ADS)

    Akande, Raphael Oluwole; Oyewande, Emmanuel Oluwole

    2016-09-01

    Different atoms achieve ionizations at different energies. Therefore, atoms are characterized by different responses to photon absorption in this study. That means there exists a coefficient for their potential for photon absorption from a photon source. In this study, we consider the manner in which molecular constituents (atoms) absorb photon from a photon source. We observe that there seems to be a common pattern of variation in the absorption of photon among the electrons in all atoms on the periodic table. We assume that the electrons closest to the nucleus (En) and the electrons closest to the outside of the atom (Eo) do not have as much potential for photon absorption as the electrons at the middle of the atom (Em). The explanation we give to this effect is that the En electrons are embedded within the nuclear influence, and similarly, Eo electrons are embedded within the influence of energies outside the atom that there exists a low potential for photon absorption for them. Unlike En and Eo, Em electrons are conditioned, such that there is a quest for balance between being influenced either by the nuclear force or forces external to the atom. Therefore, there exists a higher potential for photon absorption for Em electrons than for En and Eo electrons. The results of our derivations and analysis always produce a bell-shaped curve, instead of an increasing curve as in the ionization energies, for all elements in the periodic table. We obtained a huge data of PAPC for each of the several materials considered. The point at which two or more PAPC values cross one another is termed to be a region of conflicting order of ionization, where all the atoms absorb equal portion of the photon source at the same time. At this point, a greater fraction of the photon source is pumped into the material which could lead to an explosive response from the material. In fact, an unimaginable and unreported phenomenon (in physics) could occur, when two or more PAPCs cross, and

  12. Anti-quorum sensing activity of AgCl-TiO2 nanoparticles with potential use as active food packaging material.

    PubMed

    Naik, K; Kowshik, M

    2014-10-01

    To study the anti-quorum sensing (anti-QS) activity of AgCl-TiO2 nanoparticles (ATNPs) and its mechanism. Anti-QS activity of ATNPs was evaluated using the bacterial model Chromobacterium violaceum. Silver present in ATNPs significantly reduced violacein production in a concentration-dependent manner, indicating inhibition of QS. Anti-QS activity was confirmed by the absence of signalling molecule, oxo-octanoyl homoserine lactone during growth in the presence of ATNPs. TiO2 acted as a good supporting matrix facilitating controlled release of silver with prolonged residual activity. ATNPs are proposed as QS inhibitors with potential for use as an antipathogenic but nontoxic bioactive material. Although silver is well known for its bioactive potential of antibacterial, antifungal and antiviral properties, this study adds further note on its anti-QS activity and its potential use in food packaging industry. Food spoilage is a major socio-economic problem, and the potential role of QS in food spoilage and food safety has been indicated. Anti-QS materials such as ATNPs are proposed as efficient models for controlling food spoilage. ATNPs incorporated in food packaging materials could play an important role in food preservation and ensure safety of food by prolonging their shelf life. © 2014 The Society for Applied Microbiology.

  13. Potential Prophylactic Properties of Apple and Characterization of Potent Bioactive from cv. "Granny Smith" Displaying Strong Antimutagenicity in Models Including Human Lymphoblast TK6(+/-) Cell Line.

    PubMed

    Saxena, Sudhanshu; Verma, Jyoti; Gautam, Satyendra

    2016-02-01

    Potential prophylactic attributes in terms of antimutagenicity, antioxidant, and radioprotective properties were evaluated for 8 common apple cultivars namely "Fuji," "Golden Delicious," "Granny Smith," "Ambri Kashmiri," "Kinnaur," "Red Delicious," "Royal Gala," and "Shimla," where cultivar based significant variation was observed. Cv. "Granny Smith" displayed significantly higher and broad spectrum antimutagenicity in Escherichia coli rpoB based rifampicin resistance (Rif(R) ) assay, whereas, "Ambri Kashmiri," "Royal Gala," and "Shimla" showed lower antimutagenicity. Cultivars "Ambri Kashmiri," "Kinnaur," and "Red Delicious" exhibited strong antioxidant activity than cv. "Granny Smith" as assayed by radical scavenging, reducing potential and radioprotective property assays. The antioxidant and radioprotective properties were found to be better correlated than antimutagenicity. Suppression of error-prone DNA repair pathway (such as E. coli SOS response) was found to be one of the possible mechanisms contributing to its antimutagenicity. Phenolic extract of "Granny Smithˮ showing higher antimutagenicity was HPLC purified and the bioactive fraction (tR 35.4 min) contributing maximally (∼80%) to the observed antimutagenicity was identified as procyanidin dimer (PD) by ESI-MS/MS. The above observed antimutagenicity in bacterial assay system was well reproduced in Thymidine Kinase Mutation (TKM) assay performed using human lymphoblast cell line (TK6(+/-) ) cell line making the findings more prophylactically relevant. © 2016 Institute of Food Technologists®

  14. The bioactive potential of red raspberry (Rubus idaeus L.) leaves in exhibiting cytotoxic and cytoprotective activity on human laryngeal carcinoma and colon adenocarcinoma.

    PubMed

    Durgo, Ksenija; Belščak-Cvitanović, Ana; Stančić, Angela; Franekić, Jasna; Komes, Draženka

    2012-03-01

    In this article, the bioactive potential of red raspberry leaves, a by-product of this widely spread plant, mostly valued for its antioxidant-rich fruits, was determined. The polyphenolic profile and antioxidative properties of red raspberry leaf extract were determined and examined for potential biological activity. Cytotoxic effect, antioxidative/prooxidative effect, and effect on total glutathione concentration were determined in human laryngeal carcinoma (HEp2) and colon adenocarcinoma (SW 480) cell lines. SW 480 cells are more susceptible to raspberry leaf extract in comparison with HEp2 cells. The antioxidative nature of raspberry leaf extract was detected in HEp2 cells treated with hydrogen peroxide, as opposed to SW 480 cells, where raspberry leaf extract induced reactive oxygen species formation. Raspberry leaf extract increased total glutathione level in HEp2 cells. This effect was reinforced after 24 hours of recovery, indicating that induction was caused by products formed during cellular metabolism of compounds present in the extract. Comparison of the results obtained on these two cell lines indicates that cellular response to raspberry extract will depend on the type of the cells that are exposed to it. The results obtained confirmed the biological activity of red raspberry leaf polyphenols and showed that this traditional plant can supplement the daily intake of valuable natural antioxidants, which exhibit beneficial health effects.

  15. Oxidative stability, phenolic compounds and antioxidant potential of a virgin olive oil enriched with natural bioactive compounds.

    PubMed

    Delgado-Adámez, Jonathan; Baltasar, M Nieves Franco; Yuste, María Concepción Ayuso; Martín-Vertedor, Daniel

    2014-01-01

    The aim of this research was to evaluate strategies for the development of a virgin olive oil (VOO) enriched with aqueous extracts of olive leaf and cake to increase the necessary dose in the diet of phenolic compounds with a natural product, as phenolic compounds are involved on the healthy properties of olive oil. Different extraction procedures were evaluated with the aim of increasing the phenol content and antioxidant potential of extracts of olive leaf and cake. As leaves extract presented a higher total phenolic content, it was characterized in order to determine its phenolic profile, and was employed to enrich VOO. Diverse procedures were used to prepare enriched VOO with the leaves extract, and finally the effects of phenol enrichment were evaluated based on the antioxidant potential and oxidative stability of the prepared phenol-enriched virgin olive oils. These enriched VOOs increased significantly the content in phenolic compounds, antioxidant potential and oxidative stability 40, 4 and 1.5 fold more, respectively, than the Control oil. Furthermore, the addition of lecithin had a positive effect both on the phenolic compounds content, and on the antioxidant potential of the oils. Besides, the use of the olive leaves extract, with and without lecithin respectively, supposes a strategy potential for reducing the harmful effects that inflicts long-term preservation of VOOs and its possible deterioration.

  16. Poly(3,4-ethylenedioxythiophene):GlycosAminoGlycan Aqueous Dispersions: Toward Electrically Conductive Bioactive Materials for Neural Interfaces.

    PubMed

    Mantione, Daniele; Del Agua, Isabel; Schaafsma, Wandert; Diez-Garcia, Javier; Castro, Begona; Sardon, Haritz; Mecerreyes, David

    2016-08-01

    There is an actual need of advanced materials for the emerging field of bioelectronics. One commonly used material is the conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) ( PSS) due to its general use in organic electronics. However, depending on the application in bioelectronics, PSS is not fully biocompatible due to the high acidity of the residual sulfonate protons of PSS. In this paper, the synthesis and biocompatibility properties of new poly(3,4-ethylenedioxythiophene):GlycosAminoGlycan ( GAG) aqueous dispersions and its resulting films are shown. Thus, negatively charged GAGs as an alternative to PSS are presented. Three different commercially available GAGs, hyaluronic acid, heparin, and chondroitin sulfate are used. Indeed, GAGs dispersions are prepared through an oxidative chemical polymerization in water. Biocompatibility assays of the GAGs coatings are performed using SH-SY5Y and CCF-STTG1 cell lines and with ATP and Ca(2+) . Results show full biocompatibility and a pronounced anti-inflammatory effect. This last characteristic becomes crucial if implanted in the body. These materials can be used for in vivo applications, as transistor or electrode for electrical recording and for all the possible situations when there is contact between electronic circuits and living tissues. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Chemical and biological integration of a mouldable bioactive ceramic material capable of forming apatite in vivo in teeth.

    PubMed

    Engqvist, H; Schultz-Walz, J-E J-E; Loof, J; Botton, G A; Mayer, D; Phaneuf, M W; Ahnfelt, N-O N-O; Hermansson, L

    2004-06-01

    Chemically bonded ceramics have several advantages compared with conventional ceramics to be used as biomaterials. Especially the possibilities to harden the material at room temperature and to control the rheology are very beneficial. This paper investigates the interface formed in vivo between a calcium aluminate based dental filling material and teeth. Class 1 occlusal fillings were made in wisdom teeth and extracted after up to four weeks. Polished cross-sections of the teeth were studied with scanning electron microscopy (SEM), focused ion beam microscopy (FIB) and transmission electron microscopy (TEM). In order to analyse the distribution of elements at the interface elemental mapping was performed using STEM and EDX. The results showed that a tight bond forms between the filling material and tooth and no gap could be found even at high magnification. A 100-200 nm wide zone with an increase in oxygen was detected in the enamel next to the filling. The zone was denser than the rest of the enamel. Elemental mapping indicated an increase of silicon and a decrease of Ca at the interface. Dark field imaging and EDX mapping showed that the calcium aluminate system formed apatite in situ during hardening through precipitation.

  18. [Multiple emulsions; bioactive compounds and functional foods].

    PubMed

    Jiménez-Colmenero, Francisco

    2013-01-01

    The continued appearance of scientific evidence about the role of diet and/or its components in health and wellness, has favored the emergence of functional foods which currently constitute one of the chief factors driving the development of new products. The application of multiple emulsions opens new possibilities in the design and development of functional foods. Multiple emulsions can be used as an intermediate product (food ingredient) into technological strategies normally used in the optimization of the presence of bioactive compounds in healthy and functional foods. This paper presents a summary of the types, characteristics and formation of multiple emulsions, possible location of bioactive compounds and their potential application in the design and preparation of healthy and functional foods. Such applications are manifested particularly relevant in relation to quantitative and qualitative aspects of lipid material (reduced fat/calories and optimization of fatty acid profile), encapsulation of bioactive compounds mainly hydrophilic and sodium reduction. This strategy offers interesting possibilities regarding masking flavours and improving sensory characteristics of foods. Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.

  19. [Mouth diseases and dental materials: potential for study with cytofluorometry].

    PubMed

    Tabaj, D; Braulin, L; Frezzini, C; Visintini, E; Maglione, M; Melato, M

    2000-01-01

    The potential dental materials have of inducing mouth diseases is well known, and various methods have been developed to investigate this phenomenon. Among these there are histological studies of the pulp and periodontium exposed to dental materials, both in vivo and in vitro in humans and animals. Other studies are based on the clinical observation of the effects induced by dental materials. Aim of the paper is to evaluate the use of flow cytometry to analyse crevicular fluid to study its content in terms of inflammatory cells and inflammation mediators. Samples of crevicular fluid were collected by aspiration using a bevelled needle mounted on a 5 ml syringe from patients without periodontitis and with periodontitis and multiple heterogeneous dental restorations. This method was adopted since it allows to place the cells of the fluid in suspension. Part of the fluid was analysed by cytology and part by flow cytometry. In the patients without periodontal disease cytological examination revealed the presence of desquamated epithelial cells and colonies of cocci, rods and spirochaetae. In the patients with periodontal disease the same examination revealed, besides the above, the presence of inflammatory cells. Flow cytometry confirmed the findings of cytological examination, thus proving to be an effective method for studying crevicular fluid. This method allows to identify specific inflammatory cells or mediators of inflammation in crevicular fluid and may therefore prove to be very useful in the study of alterations induced by some dental materials at the level of the gingival sulcus.

  20. A multifunctional bioactive material that stimulates osteogenesis and promotes the vascularization bone marrow stem cells and their resistance to bacterial infection.

    PubMed

    Ma, Chuang; Wei, Qin; Cao, Bo; Cheng, Xinchun; Tian, Juling; Pu, Hongwei; Yusufu, Aihemaitijiang; Cao, Li

    2017-01-01

    The main limitation of tissue engineering lies in the inability to stimulate osteogenesis, angiogenesis of stem cells and broad-spectrum antimicrobial activity. However, the development of multifunctional bioactive materials with these capabilities remains a great challenge. In this study, we prepared mesoporous silica nanoparticles encapsulated with silver nanocrystals (AG-MSN) with uniform sphere size and mesopores. Platelet-derived growth factor BB (PDGF-BB) was effectively loaded in the AG-MSN mesopores (P-AG-MSN). The silicon ions (Si) released by P-AG-MSN stimulate osteogenic differentiation of bone marrow stromal cells (BMSC) by activating the alkaline phosphatase (ALP) activity of bone-related genes and increasing protein (OCN, RUNX2 and OPN) expression. Ag+ ions could be slowly released from the interior of the shell, highlighting their durable antibacterial activity. The sustained release of PDGF-BB from P-AG-MSN stimulated the angiogenic differentiation of BMSC, as indicated by the enhanced secretion of vascular endothelial growth factor (VEGF), HIF-1α, HGF and ANG-1 and protein expression. Our results show that P-AG-MSN can clearly promote BMSC osteostimulation and vascularization. This research serves as a preliminary study of the utilization of this multifunctional mixture to fabricate a new active biological scaffold that integrates BMSC osteostimulation, vascularization and bactericidal effects by 3D printing technology.

  1. Production of chitin and bioactive materials from Black tiger shrimp (Penaeus monodon) shell waste by the treatment of bacterial protease cocktail.

    PubMed

    Paul, Tanamy; Halder, Suman K; Das, Arpan; Ghosh, Kuntal; Mandal, Arpita; Payra, Pijush; Barman, Prasenjit; Das Mohapatra, Pradeep K; Pati, Bikas Ranjan; Mondal, Keshab C

    2015-08-01

    The main objective of this study was to obtain chitin in pure form from a new crustacean waste material for industrial applications. Black tiger shrimp shell wastes are a rich source of protein and valuable bioactive carbohydrate polymers such as chitin. After removal of carotenoid, Black tiger shrimp shell wastes (BTSHWs) were treated with chemicals and protease enzyme to extract chitin. Box-Behnken response surface methodology was applied to optimize the deproteinization process to obtain chitin. At optimal pH (8.82), temperature (50.05 °C), agitation speed (100.98 rpm), enzyme substrate ratio of 1:8 (wv(-1)) and 72 h of incubation with Paenibacillus woosongensis TKB2 crude protease cocktail, 80 % deproteinization was found along with 77.28 % recovery of chitin. The valuable oligopeptides were determined by MALDI-TOF analysis and analysis of adequate amount of free amino acids in protein hydrolysate from BTSHW, indicating a high nutritional value used for food, feed or as a nitrogen source in growth medium for microorganisms. The chitin obtained was compared with the commercial chitin using scanning electron microscopy, Fourier transform infrared spectrometer, X-ray diffraction and (13)C CP/MAS-NMR. Chitin obtained from crude protease treatment showed comparable physicochemical and structural properties to those of the commercial chitin. The carotenoid obtained after treatment can be used for medicinal purpose.

  2. A multifunctional bioactive material that stimulates osteogenesis and promotes the vascularization bone marrow stem cells and their resistance to bacterial infection

    PubMed Central

    Cao, Bo; Cheng, Xinchun; Tian, Juling; Pu, Hongwei; Yusufu, Aihemaitijiang; Cao, Li

    2017-01-01

    The main limitation of tissue engineering lies in the inability to stimulate osteogenesis, angiogenesis of stem cells and broad-spectrum antimicrobial activity. However, the development of multifunctional bioactive materials with these capabilities remains a great challenge. In this study, we prepared mesoporous silica nanoparticles encapsulated with silver nanocrystals (AG-MSN) with uniform sphere size and mesopores. Platelet-derived growth factor BB (PDGF-BB) was effectively loaded in the AG-MSN mesopores (P-AG-MSN). The silicon ions (Si) released by P-AG-MSN stimulate osteogenic differentiation of bone marrow stromal cells (BMSC) by activating the alkaline phosphatase (ALP) activity of bone-related genes and increasing protein (OCN, RUNX2 and OPN) expression. Ag+ ions could be slowly released from the interior of the shell, highlighting their durable antibacterial activity. The sustained release of PDGF-BB from P-AG-MSN stimulated the angiogenic differentiation of BMSC, as indicated by the enhanced secretion of vascular endothelial growth factor (VEGF), HIF-1α, HGF and ANG-1 and protein expression. Our results show that P-AG-MSN can clearly promote BMSC osteostimulation and vascularization. This research serves as a preliminary study of the utilization of this multifunctional mixture to fabricate a new active biological scaffold that integrates BMSC osteostimulation, vascularization and bactericidal effects by 3D printing technology. PMID:28358890

  3. Bioactive Carbohydrates and Peptides in Foods: An Overview of Sources, Downstream Processing Steps and Associated Bioactivities.

    PubMed

    Hayes, Maria; Tiwari, Brijesh K

    2015-09-17

    Bioactive peptides and carbohydrates are sourced from a myriad of plant, animal and insects and have huge potential for use as food ingredients and pharmaceuticals. However, downstream processing bottlenecks hinder the potential use of these natural bioactive compounds and add cost to production processes. This review discusses the health benefits and bioactivities associated with peptides and carbohydrates of natural origin and downstream processing methodologies and novel processes which may be used to overcome these.

  4. Bioactive Carbohydrates and Peptides in Foods: An Overview of Sources, Downstream Processing Steps and Associated Bioactivities

    PubMed Central

    Hayes, Maria; Tiwari, Brijesh K.

    2015-01-01

    Bioactive peptides and carbohydrates are sourced from a myriad of plant, animal and insects and have huge potential for use as food ingredients and pharmaceuticals. However, downstream processing bottlenecks hinder the potential use of these natural bioactive compounds and add cost to production processes. This review discusses the health benefits and bioactivities associated with peptides and carbohydrates of natural origin and downstream processing methodologies and novel processes which may be used to overcome these. PMID:26393573

  5. Nanoparticulate bioactive-glass-reinforced gellan-gum hydrogels for bone-tissue engineering.

    PubMed

    Gantar, Ana; da Silva, Lucilia P; Oliveira, Joaquim M; Marques, Alexandra P; Correlo, Vitor M; Novak, Saša; Reis, Rui L

    2014-10-01

    This work presents bioactive-glass-reinforced gellan-gum spongy-like hydrogels (GG-BAG) as novel hydrophilic materials for use as the scaffolding in bone-tissue engineering. The reinforcement with bioactive-glass particles resulted in an improvement to the microstructure and to the mechanical properties of the material. These mechanical properties were found to be dependent on the composition and improved with the amount of bioactive glass; however, values necessary to accommodate biomechanical loading were not achieved in this study. Nevertheless, by incorporating the bioactive-glass particles, the composite material acquired the ability to form an apatite layer when soaked in simulated body fluid. Furthermore, human-adipose-derived stem cells were able to adhere and spread within the gellan-gum, spongy-like hydrogels reinforced with the bioactive glass, and remain viable, which is an important result when considering their use in bone-tissue engineering. Thus, hydrogels based on gellan gum and bioactive glass are promising biomaterials for use either alone or with cells, and with the potential for use in osteogenic differentiation. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Evaluation of bioactive compounds and antioxidant potential of hydroethanolic extract of Moringa oleifera Lam. from Rajasthan, India.

    PubMed

    Vats, Sharad; Gupta, Tanya

    2017-01-01

    Moringa oleifera Lam., the miracle tree, is widely used as a traditional medicine. The analyses of phytochemicals and antioxidant potential of hydroethanolic extract of various plant parts of M. oleifera revealed that leaves possessed the highest content of total phenolics (9.58 mg/g), β-carotene (14.10 mg/g) and lycopene (2.60 mg/g). Flowers and bark showed the highest content of total flavonoids (3.5 mg/g) and anthocyanin (52.80 mg/g), respectively. Leaves also showed maximum antioxidant potential using nitric oxide scavenging assay (IC50 - 120 µg/ml) and deoxyribose degradation assay (IC50-178 µg/ml). Highest DPPH radical scavenging activity was observed in flowers (IC50-405 µg/ml). The GC-MS study revealed the presence of 29, 36 and 24 compounds in bark, leaf and flower, respectively. The major constituent identified were epiglobulol (41.68% in bark), phytol (23.54% in leaf) and β-sitosterol (15.35% in flower).The phytochemicals identified possess several therapeutic activity, including antioxidant potential, which was confirmed through earlier reports. Moreover, the presence of 1,1,3-triethoxubutane in all the plant parts analyzed, projects it as an important source of waste water treatment as hydrophobic modifiers.

  7. Optimizing Interacting Potentials to Form Targeted Materials Structures

    SciTech Connect

    Torquato, Salvatore

    2015-09-28

    Conventional applications of the principles of statistical mechanics (the "forward" problems), start with particle interaction potentials, and proceed to deduce local structure and macroscopic properties. Other applications (that may be classified as "inverse" problems), begin with targeted configurational information, such as low-order correlation functions that characterize local particle order, and attempt to back out full-system configurations and/or interaction potentials. To supplement these successful experimental and numerical "forward" approaches, we have focused on inverse approaches that make use of analytical and computational tools to optimize interactions for targeted self-assembly of nanosystems. The most original aspect of our work is its inherently inverse approach: instead of predicting structures that result from given interaction potentials among particles, we determine the optimal potential that most robustly stabilizes a given target structure subject to certain constraints. Our inverse approach could revolutionize the manner in which materials are designed and fabricated. There are a number of very tangible properties (e.g. zero thermal expansion behavior), elastic constants, optical properties for photonic applications, and transport properties.

  8. Biomimetic component coating on 3D scaffolds using high bioactivity of mesoporous bioactive ceramics.

    PubMed

    Yun, Hui-suk; Kim, Sang-Hyun; Khang, Dongwoo; Choi, Jungil; Kim, Hui-hoon; Kang, Minji

    2011-01-01

    Mesoporous bioactive glasses (MBGs) are very attractive materials for use in bone tissue regeneration because of their extraordinarily high bone-forming bioactivity in vitro. That is, MBGs may induce the rapid formation of hydroxy apatite (HA) in simulated body fluid (SBF), which is a major inorganic component of bone extracellular matrix (ECM) and comes with both good osteoconductivity and high affinity to adsorb proteins. Meanwhile, the high bioactivity of MBGs may lead to an abrupt initial local pH variation during the initial Ca ion-leaching from MBGs at the initial transplant stage, which may induce unexpected negative effects on using them in in vivo application. In this study we suggest a new way of using MBGs in bone tissue regeneration that can improve the strength and make up for the weakness of MBGs. We applied the outstanding bone-forming bioactivity of MBG to coat the main ECM components HA and collagen on the MBG-polycarplolactone (PCL) composite scaffolds for improving their function as bone scaffolds in tissue regeneration. This precoating process can also expect to reduce initial local pH variation of MBGs. The MBG-PCL scaffolds were immersed in the mixed solution of the collagen and SBF at 37°C for 24 hours. The coating of ECM components on the MBG-PCL scaffolds and the effect of ECM coating on in vitro cell behaviors were confirmed. The ECM components were fully coated on MBG-PCL scaffolds after immersing in SBF containing dilute collagen-I solution only for 24 hours due to the high bone-forming bioactivity of MBG. Both cell affinity and osteoconductivity of MBG-PCL scaffolds were dramatically enhanced by this precoating process. The precoating process of ECM components on MBG-PCL scaffold using a high bioactivity of MBG was not only effective in enhancing the functionality of scaffolds but also effective in eliminating the unexpected side effect. The MBG-PCL scaffold-coated ECM components ideally satisfied the required conditions of scaffold in

  9. Laser cladding of bioactive glass coatings.

    PubMed

    Comesaña, R; Quintero, F; Lusquiños, F; Pascual, M J; Boutinguiza, M; Durán, A; Pou, J

    2010-03-01

    Laser cladding by powder injection has been used to produce bioactive glass coatings on titanium alloy (Ti6Al4V) substrates. Bioactive glass compositions alternative to 45S5 Bioglass were demonstrated to exhibit a gradual wetting angle-temperature evolution and therefore a more homogeneous deposition of the coating over the substrate was achieved. Among the different compositions studied, the S520 bioactive glass showed smoother wetting angle-temperature behavior and was successfully used as precursor material to produce bioactive coatings. Coatings processed using a Nd:YAG laser presented calcium silicate crystallization at the surface, with a uniform composition along the coating cross-section, and no significant dilution of the titanium alloy was observed. These coatings maintain similar bioactivity to that of the precursor material as demonstrated by immersion in simulated body fluid. Copyright 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  10. A new synthesis route to high surface area sol gel bioactive glass through alcohol washing

    PubMed Central

    M. Mukundan, Lakshmi; Nirmal, Remya; Vaikkath, Dhanesh; Nair, Prabha D.

    2013-01-01

    Bioactive glass is one of the widely used bone repair material due to its unique properties like osteoconductivity, osteoinductivity and biodegradability. In this study bioactive glass is prepared by the sol gel process and stabilized by a novel method that involves a solvent instead of the conventional calcinations process. This study represents the first attempt to use this method for the stabilization of bioactive glass. The bioactive glass stabilized by this ethanol washing process was characterized for its physicochemical and biomimetic property in comparison with similar composition of calcined bioactive glass. The compositional similarity of the two stabilized glass powders was confirmed by spectroscopic and thermogravimetric analysis. Other physicochemical characterizations together with the cell culture studies with L929 fibroblast cells and bone marrow mesenchymal stem cells proved that the stabilization was achieved with the retention of its inherent bioactive potential. However an increase in the surface area of the glass powder was obtained as a result of this ethanol washing process and this add up to the success of the study. Hence the present study exhibits a promising route for high surface area bioactive glass for increasing biomimicity. PMID:23512012

  11. New bioactive hybrid material of nano-hydroxyapatite based on N-carboxyethylchitosan for bone tissue engineering

    NASA Astrophysics Data System (ADS)

    Lu, Yan; Zhu, Aiping; Wang, Wanpeng; Shi, Hongchan

    2010-09-01

    N-carboxyethylchitosan/nano-hydroxyapatite (NCECS/HA) composite films were fabricated and their potential applications in guiding bone regeneration were investigated in terms of their in vitro cellular activity. Fourier ransform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were used to investigate the structure and composition of the composite film. Field Emission scanning electron microscopy (FESEM) revealed that HA nanoparticles were dispersed homogeneously in NCECS matrix. The composite film has sufficient mechanical properties for tissue engineering scaffold. The composite film was found to have better cartilage cell adhesion and growth than pure NCECS film.

  12. Potential Applications of Smart Multifunctional Wearable Materials to Gerontology.

    PubMed

    Armstrong, David G; Najafi, Bijan; Shahinpoor, Mohsen

    2017-01-01

    Smart multifunctional materials can play a constructive role in addressing some very important aging-related issues. Aging affects the ability of older adults to continue to live safely and economically in their own residences for as long as possible. Thus, there will be a greater need for preventive, acute, rehabilitative, and long-term health care services for older adults as well as a need for tools to enable them to function independently during daily activities. The objective of this paper is, thus, to present a comprehensive review of some potential smart materials and their areas of applications to gerontology. Thus, brief descriptions of various currently available multifunctional smart materials and their possible applications to aging-related problems are presented. It is concluded that some of the most important applications to geriatrics may be in various sensing scenarios to collect health-related feedback or information and provide personalized care. Further described are the applications of wearable technologies to aging-related needs, including devices for home rehabilitation, remote monitoring, social well-being, frailty monitoring, monitoring of diabetes and wound healing and fall detection or prediction. It is also concluded that wearable technologies, when combined with an appropriate application and with appropriate feedback, may help improve activities and functions of older patients with chronic diseases. Finally, it is noted that methods developed to measure what one collectively manages in this population may provide a foundation to establish new definitions of quality of life. © 2017 S. Karger AG, Basel.

  13. Titanium alloy as a potential low radioactivation vacuum material

    SciTech Connect

    Kamiya, Junichiro Hikichi, Yusuke; Kinsho, Michikazu; Ogiwara, Norio; Fukuda, Mitsuhiro; Hamatani, Noriaki; Hatanaka, Kichiji; Kamakura, Keita; Takahisa, Keiji

    2015-05-15

    For the vacuum systems of high-intensity beam accelerators, low radioactivation materials with good vacuum characteristics and high mechanical strength are required. The titanium alloy Ti-6Al-4V was investigated as a potential low activation vacuum material with high mechanical strength for the fabrication of vacuum components, particularly the flanges of beam pipes, in the J-PARC 3 GeV synchrotron. The dose rate of Ti-6Al-4V when irradiated by a 400 MeV proton was observed to decrease more rapidly than that of stainless steel. Furthermore, the generated radioactive isotopes were nuclides with relatively short half-lives. The outgassing rate per unit area of Ti-6Al-4V was approximately 10{sup −8 }Pa m{sup 3}/s m{sup 2} after pumping for 100 h, which is the same as the typical value for stainless steel. Additionally, the hydrogen concentration in bulk Ti-6Al-4V was reduced to approximately 1 ppm by vacuum firing at 700 °C for 9 h; the mechanical strength was not reduced by this process. These results indicate that Ti-6Al-4V is a good candidate for use as a low activation vacuum material with high mechanical strength.

  14. Transition Metal Oxide Alloys as Potential Solar Energy Conversion Materials

    SciTech Connect

    Toroker, Maytal; Carter, Emily A.

    2013-02-21

    First-row transition metal oxides (TMOs) are inexpensive potentia alternative materials for solar energy conversion devices. However, some TMOs, such as manganese(II) oxide, have band gaps that are too large for efficiently absorbing solar energy. Other TMOs, such as iron(II) oxide, have conduction and valence band edges with the same orbital character that may lead to unfavorably high electron–hole recombination rates. Another limitation of iron(II) oxide is that the calculated valence band edge is not positioned well for oxidizing water. We predict that key properties, including band gaps, band edge positions, and possibly electron–hole recombination rates, may be improved by alloying TMOs that have different band alignments. A new metric, the band gap center offset, is introduced for simple screening of potential parent materials. The concept is illustrated by calculating the electronic structure of binary oxide alloys that contain manganese, nickel, iron, zinc, and/or magnesium, within density functional theory (DFT)+U and hybrid DFT theories. We conclude that alloys of iron(II) oxide are worth evaluating further as solar energy conversion materials.

  15. Hypoxylon sp., an endophyte of Persea indica, producing 1,8-cineole and other bioactive volatiles with fuel potential.

    PubMed

    Tomsheck, Angela R; Strobel, Gary A; Booth, Eric; Geary, Brad; Spakowicz, Dan; Knighton, Berk; Floerchinger, Cody; Sears, Joe; Liarzi, Orna; Ezra, David

    2010-11-01

    An endophytic fungus of Persea indica was identified, on the basis of its anamorphic stage, as Nodulosporium sp. by SEM. Partial sequence analysis of ITS rDNA revealed the identity of the teleomorphic stage of the fungus as Hypoxylon sp. It produces an impressive spectrum of volatile organic compounds (VOCs), most notably 1,8-cineole, 1-methyl-1,4-cyclohexadiene, and tentatively identified (+)-.alpha.-methylene-.alpha.-fenchocamphorone, among many others, most of which are unidentified. Six-day-old cultures of Hypoxylon sp. displayed maximal VOC-antimicrobial activity against Botrytis cinerea, Phytophthora cinnamomi, Cercospora beticola, and Sclerotinia sclerotiorum suggesting that the VOCs may play some role in the biology of the fungus and its survival in its host plant. Media containing starch- or sugar-related substrates best supported VOC production by the fungus. Direct on-line quantification of VOCs was measured by proton transfer mass spectrometry covering a continuous range with optimum VOC production occurred at 6 days at 145 ppmv with a rate of production of 7.65 ppmv/h. This report unequivocally demonstrates that 1,8-cineole (a monoterpene) is produced by a microorganism, which represents a novel and important source of this compound. This monoterpene is an octane derivative and has potential use as a fuel additive as do the other VOCs of this organism. Thus, fungal sourcing of this compound and other VOCs as produced by Hypoxylon sp. greatly expands their potential applications in medicine, industry, and energy production.

  16. Bioactivity and structure-activity relationship of cinnamic acid esters and their derivatives as potential antifungal agents for plant protection.

    PubMed

    Zhou, Kun; Chen, Dongdong; Li, Bin; Zhang, Bingyu; Miao, Fang; Zhou, Le

    2017-01-01

    A series of cinnamic acid esters and their derivatives were synthesized and evaluated for antifungal activities in vitro against four plant pathogenic fungi by using the mycelium growth rate method. Structure-activity relationship was derived also. Almost all of the compounds showed some inhibition activity on each of the fungi at 0.5 mM. Eight compounds showed the higher average activity with average EC50 values of 17.4-28.6 μg/mL for the fungi than kresoxim-methyl, a commercial fungicide standard, and ten compounds were much more active than commercial fungicide standards carbendazim against P. grisea or kresoxim-methyl against both P. grisea and Valsa mali. Compounds C1 and C2 showed the higher activity with average EC50 values of 17.4 and 18.5 μg/mL and great potential for development of new plant antifungal agents. The structure-activity relationship analysis showed that both the substitution pattern of the phenyl ring and the alkyl group in the alcohol moiety significantly influences the activity. There exists complexly comprehensive effect between the substituents on the phenyl ring and the alkyl group in the alcohol moiety on the activity. Thus, cinnamic acid esters showed great potential the development of new antifungal agents for plant protection due to high activity, natural compounds or natural compound framework, simple structure, easy preparation, low-cost and environmentally friendly.

  17. Bioactivity and structure-activity relationship of cinnamic acid esters and their derivatives as potential antifungal agents for plant protection

    PubMed Central

    Li, Bin; Zhang, Bingyu; Miao, Fang

    2017-01-01

    A series of cinnamic acid esters and their derivatives were synthesized and evaluated for antifungal activities in vitro against four plant pathogenic fungi by using the mycelium growth rate method. Structure−activity relationship was derived also. Almost all of the compounds showed some inhibition activity on each of the fungi at 0.5 mM. Eight compounds showed the higher average activity with average EC50 values of 17.4–28.6 μg/mL for the fungi than kresoxim-methyl, a commercial fungicide standard, and ten compounds were much more active than commercial fungicide standards carbendazim against P. grisea or kresoxim-methyl against both P. grisea and Valsa mali. Compounds C1 and C2 showed the higher activity with average EC50 values of 17.4 and 18.5 μg/mL and great potential for development of new plant antifungal agents. The structure−activity relationship analysis showed that both the substitution pattern of the phenyl ring and the alkyl group in the alcohol moiety significantly influences the activity. There exists complexly comprehensive effect between the substituents on the phenyl ring and the alkyl group in the alcohol moiety on the activity. Thus, cinnamic acid esters showed great potential the development of new antifungal agents for plant protection due to high activity, natural compounds or natural compound framework, simple structure, easy preparation, low-cost and environmentally friendly. PMID:28423022

  18. Selecting bioactive phenolic compounds as potential agents to inhibit proliferation and VEGF expression in human ovarian cancer cells

    PubMed Central

    HE, ZHIPING; LI, BO; RANKIN, GARY O.; ROJANASAKUL, YON; CHEN, YI CHARLIE

    2015-01-01

    Ovarian cancer is a disease that continues to cause mortality in female individuals worldwide. Ovarian cancer is challenging to treat due to emerging resistance to chemotherapy, therefore, the identification of effective novel chemotherapeutic agents is important. Polyphenols have demonstrated potential in reducing the risk of developing numerous types of cancer, as well reducing the risk of cancer progression, due to their ability to reduce cell viability and vascular endothelial growth factor (VEGF) expression. In the present study, eight phenolic compounds were screened in two human ovarian cancer cell lines (OVCAR-3 and A2780/CP70) to determine their effect on proliferation suppression and VEGF protein secretion inhibition, in comparison to cisplatin, a conventional chemotherapeutic agent. The current study identified that 40 μM gallic acid (GA) exhibited the greatest inhibitory effect on OVCAR-3 cell viability, compared with all of the phenolic compounds investigated. Similarly to cisplatin, baicalein, GA, nobiletin, tangeretin and baicalin were all identified to exhibit significant VEGF inhibitory effects from ELISA results. Furthermore, western blot analysis indicated that GA effectively decreased the level of the VEGF-binding protein hypoxia-inducible factor-1α in the ovarian cancer cell line. Considering the results of the present study, GA appears to inhibit cell proliferation and, thus, is a potential agent for the treatment of ovarian cancer. PMID:25663929

  19. A study of the ability of bioactive extracts from brewers' spent grain to enhance the antioxidant and immunomodulatory potential of food formulations following in vitro digestion.

    PubMed

    McCarthy, Aoife L; O'Callaghan, Yvonne C; Connolly, Alan; Piggott, Charles O; FitzGerald, Richard J; O'Brien, Nora M

    2015-03-01

    Bioactivity of a snack-bar, chocolate-drink and yogurt fortified with brewers' spent grain (BSG) phenolic extracts (P2 or B2) or protein hydrolysates (barley protein hydrolysate (BPH), BPH < 3 kDa, BPH < 5 kDa, BPH > 5 kDa) was measured following gastrointestinal in vitro digestion. Concentrations of 0.5 and 0.1% (v/v) digestates were chosen for addition to Caco-2 and Jurkat T cells, respectively. Yogurt and B2 digestate protected against H2O2-induced DNA damage in Caco-2 cells (p < 0.05), by the comet assay. Snack-bar digestates possessed significant (p < 0.05) immunomodulatory effects, measured by ELISA in concanavalin-A stimulated Jurkat T cells. Addition of BPH enhanced (p < 0.05) the IFN-γ reducing capacity of the snack-bar while addition of BPH < 3 and < 5 kDa reduced IL-2 production to a greater extent than unfortified yogurt (p < 0.05). Selected BSG components can enhance the antioxidant and anti-inflammatory potential of foods.

  20. Development of an analytical strategy for the identification of potential bioactive peptides generated by in vitro tryptic digestion of fish muscle proteins.

    PubMed

    Capriotti, Anna Laura; Cavaliere, Chiara; Foglia, Patrizia; Piovesana, Susy; Samperi, Roberto; Zenezini Chiozzi, Riccardo; Laganà, Aldo

    2015-01-01

    In the last years, food proteins and peptides are attracting great attention because of the emergence of a new field, that of food-derived bioactive peptides. This paper presents a comparison and evaluation of four different experiments for the identification of sarcoplasmic and myofibrillar fish peptides. This study is aimed at the development of a simple and fast method for the identification of peptides that could arise from fish meat if trypsin was the only digestive enzyme acting on fish meat proteins. In particular, we tested the use of ultrafiltration membranes with a molecular weight cutoff of 3,000 Da. Data analysis has shown that the experiment in which there is neither precipitation nor an ultrafiltration step performed better and allowed the identification of a larger number of peptides and potential antimicrobial peptides (AMPs); this workflow provided 473 and 398 total identified peptides and 44 and 18 AMPs for sarcoplasmic and myofibrillar extracts, respectively. This protocol is found to be faster and more straightforward than the other three tested workflows. The developed strategy could be also useful for other food matrices and could provide information about food quality and safety control.

  1. A new approach for the one-step synthesis of bioactive PS vs. PMMA silica hybrid microspheres as potential drug delivery systems.

    PubMed

    Angelopoulou, A; Efthimiadou, E K; Boukos, N; Kordas, G

    2014-05-01

    In this work, hybrid microspheres were prepared in a two-step process combining the emulsifier free-emulsion polymerization and the sol-gel coating method. In the first step, polystyrene (St) and poly(methyl methacrylate) (PMMA) microspheres were prepared as sacrificial template and in the second step a silanol shell was fabricated. The functionalized surface of the hybrid microspheres by silane analogs (APTES, TEOS) resulted in enhanced effects. The hollow microspheres were resulted either in an additional step by template dissolution and/or during the coating process. The microspheres' surface interactions and the size distribution were optimized by treatment in simulated body fluids, which resulted in the in vitro prediction of bioactivity. The bioassay test indicated that the induced hydroxyapatite resembled in structure to naturally occurring bone apatite. The drug doxorubicin (DOX) was used as a model entity for the evaluation of drug loading and release. The drug release study was performed in two different pH conditions, at acidic (pH=4.5) close to cancer cell environment and at slightly basic pH (pH=7.4) resembling the orthopedic environment. The results of the present study indicated promising hybrid microspheres for the potential application as drug delivery vehicles, for dual orthopedic functionalities in bone defects, bone inflammation, bone cancer and bone repair. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Isolation, purification and N-terminal sequencing of a bioactive peptide that alters action potentials from the venom of Buthus martensii Karsch.

    PubMed

    Hahin, R; Chen, Z; Reddy, G; Li, Y

    2001-08-01

    A bioactive peptide that extensively prolongs action potentials (APs) in frog nerve has been isolated and purified from the venom of the scorpion Buthus martensii Karsch (BMK). The peptide, designated as BMK 18(2), was purified using gel filtration, ion exchange, FPLC, and HPLC chromatography. APs recorded in the presence of nanomolar concentrations of the peptide were extensively prolonged with some attenuation in their heights. The N-terminal sequence of BMK 18(2) was found to be: VRDAYIAEDYD-VYH-ARDA. Sequence similarity comparisons to other alpha-scorpion toxins suggest that the two blanks in the sequences are cysteines. The molecular weight (M.W.) of BMK 18(2) was determined by LC/MS/MS to be 7185 Da. Since the peptide prolongs APs when both K+ and Ca++ channels were blocked and shows sequence similarity to other alpha-neurotoxins, it appears likely that BMK 18(2) acts to alter Na channel inactivation to produce its effect.

  3. Exploring the inhibitory potential of bioactive compound from Luffa acutangula against NF-κB-A molecular docking and dynamics approach.

    PubMed

    Ramar, Vanajothi; Pappu, Srinivasan

    2016-06-01

    Nuclear factor kappa B (NF-κB) is a transcription factor, plays a crucial role in the regulation of various physiological processes such as differentiation, cell proliferation and apoptosis. It also coordinates the expression of various soluble proinflammatory mediators like cytokines and chemokines. The 1, 8-dihydroxy-4-methylanthracene-9, 10-dione (DHMA) was isolated from Luffa acutangala and its in vitro cytotoxic activity against NCI-H460 cells was reported earlier. It also effectively induces apoptosis through suppressing the expression NF-κB protein. Based on experimental evidence, the binding affinity of compound 1 with NF-κB p50 (monomer) and NF-κB-DNA was investigated using molecular docking and its stability was confirmed through molecular dynamic simulation. The reactivity of the compound was evaluated using density functional theory (DFT) calculation. From the docking results, we noticed that the hydroxyl group of DHMA forms hydrogen bond interactions with polar and negatively charged amino acid Tyr57 and Asp239 and the protein-ligand complex was stabilized through pi-pi stacking with the help of polar amino acid His114, which plays a key role in binding of NF-κB to DNA at a site of DNA-binding region (DBR). The result indicates that the isolated bioactive compound DHMA might have altered the binding affinity between DNA and NF-κB. These findings suggest that potential use of DHMA in cancer chemoprevention and therapeutics.

  4. Detection of small bioactive peptides from Atlantic herring (Clupea harengus L.).

    PubMed

    Pampanin, Daniela M; Larssen, Eivind; Provan, Fiona; Sivertsvik, Morten; Ruoff, Peter; Sydnes, Magne O

    2012-04-01

    Recent research has shown that fish residual materials contain a range of components with interesting biological activity. Therefore, there is a great potential in the marine bioprocess industry to utilize these by-products as starting material for generating more valuable products. The aim of the present study was to search for bioactive peptides (in particular small natural bioactive peptides with molecular weight lower than 10 kDa) in Atlantic herring (Clupea harengus L.) by-products such as skin and more general residual materials. By such means a range of peptides with claimed interesting biological activities was found. Herein the activity of the detected bioactive peptides and strategies for isolating peptide fragments containing the bioactive motif is discussed. Identification of bioactive peptides in crude peptide/protein sources (skin and residual materials) was performed directly using a combination of mass spectrometry (Orbitrap), bioinformatics and database search. This method was a good angle of approach in order to map the potential in new species and species that have been very little studied. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Bioactive Potential of 3D-Printed Oleo-Gum-Resin Disks: B. papyrifera, C. myrrha, and S. benzoin Loading Nanooxides-TiO2, P25, Cu2O, and MoO3.

    PubMed

    Horst, Diogo José; Tebcherani, Sergio Mazurek; Kubaski, Evaldo Toniolo; de Almeida Vieira, Rogério

    2017-01-01

    This experimental study investigates the bioactive potential of filaments produced via hot melt extrusion (HME) and intended for fused deposition modeling (FDM) 3D printing purposes. The oleo-gum-resins from benzoin, myrrha, and olibanum in pure state and also charged with 10% of metal oxide nanoparticles, TiO2, P25, Cu2O, and MoO3, were characterized by ultraviolet-visible (UV-Vis) and Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray microanalysis (EDXMA), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). Disks were 3D-printed into model geometries (10 × 5 mm) and the disk-diffusion methodology was used for the evaluation of antimicrobial and antifungal activity of materials in study against the clinical isolates: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. Due to their intrinsic properties, disks containing resins in pure state mostly prevent surface-associated growth; meanwhile, disks loaded with 10% oxides prevent planktonic growth of microorganisms in the susceptibility assay. The microscopy analysis showed that part of nanoparticles was encapsulated by the biopolymeric matrix of resins, in most cases remaining disorderly dispersed over the surface of resins. Thermal analysis shows that plant resins have peculiar characteristics, with a thermal behavior similar to commercial available semicrystalline polymers, although their structure consists of a mix of organic compounds.

  6. Multicomponent determination of traditional Chinese medicine preparation yin-zhi-huang injection by LC-MS/MS for screening of its potential bioactive candidates using HepaRG cells.

    PubMed

    Rao, Zhi; Zhang, Fan; Zhang, Xiao-Yi; Zhang, Guo-Qiang; Ma, Yan-Rong; Zhou, Yan; Qin, Hong-Yan; Wu, Xin-An; Wei, Yu-Hui

    2017-07-29

    Yin-zhi-huang (YZH) injection is an injectable multiherbal prescription derived from the ancient Chinese medicine formula of Yin-chen-hao-tang, which is widely used in the clinic for the treatment of jaundice and chronic liver diseases. To date, the systematic study of the components in this multiherbal prescription still lacks suitable analytical methods that are able to simultaneously detect a broad array of components at low concentrations. In this study, a new liquid chromatography-tandem mass spectrometry method using dynamic multiple reaction monitoring mode was developed to determine multiple peaks in traditional Chinese medicine preparation YZH injection. This simple, selective and sensitive method enabled the quantification of 22 components with standard materials with a lower limit of quantification of 1.46-12.5 ng/mL in cell lysates. This method was successfully applied to celluar uptake and binding investigation of components in YZH injection. The results indicated that this strategy might be a useful approach for rapidly screening of the potential bioactive candidates from YZH injection, and the discovered candidates could be used to investigate the pharmacodynamics in further studies. Copyright © 2017 John Wiley & Sons, Ltd.

  7. Bioactive Potential of 3D-Printed Oleo-Gum-Resin Disks: B. papyrifera, C. myrrha, and S. benzoin Loading Nanooxides—TiO2, P25, Cu2O, and MoO3

    PubMed Central

    Tebcherani, Sergio Mazurek; Kubaski, Evaldo Toniolo; de Almeida Vieira, Rogério

    2017-01-01

    This experimental study investigates the bioactive potential of filaments produced via hot melt extrusion (HME) and intended for fused deposition modeling (FDM) 3D printing purposes. The oleo-gum-resins from benzoin, myrrha, and olibanum in pure state and also charged with 10% of metal oxide nanoparticles, TiO2, P25, Cu2O, and MoO3, were characterized by ultraviolet-visible (UV-Vis) and Fourier transform infrared (FTIR) spectroscopy, energy-dispersive X-ray microanalysis (EDXMA), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). Disks were 3D-printed into model geometries (10 × 5 mm) and the disk-diffusion methodology was used for the evaluation of antimicrobial and antifungal activity of materials in study against the clinical isolates: Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. Due to their intrinsic properties, disks containing resins in pure state mostly prevent surface-associated growth; meanwhile, disks loaded with 10% oxides prevent planktonic growth of microorganisms in the susceptibility assay. The microscopy analysis showed that part of nanoparticles was encapsulated by the biopolymeric matrix of resins, in most cases remaining disorderly dispersed over the surface of resins. Thermal analysis shows that plant resins have peculiar characteristics, with a thermal behavior similar to commercial available semicrystalline polymers, although their structure consists of a mix of organic compounds. PMID:28811751

  8. A bioactive and bioresorbable porous cubic composite scaffold loaded with bone marrow aspirate: a potential alternative to autogenous bone grafting.

    PubMed

    Tanaka, Kojiro; Takemoto, Mitsuru; Fujibayashi, Shunsuke; Neo, Masashi; Shikinami, Yasuo; Nakamura, Takashi

    2011-03-15

    Experimental animal study. To investigate the osteogenic properties of a particulate uncalcined, unsintered hydroxyapatite/polydllactide (u-HA/PdlLA) composite scaffold loaded with bone marrow aspirate (BMA). Because of the high morbidity associated with bone graft harvesting, current research in spine surgery has largely focused on bone graft alternatives involving a combination of scaffolds and osteogenic substances. BMA is obtained by a simple and relatively noninvasive method and can easily be clinically applied as an osteogenic material. However, few studies have reported successful posterolateral spinal fusion (PLF) with BMA-loaded synthetic materials. Porous u-HA/PdlLA composites loaded with BMA were used as bone graft substitutes. In experiment 1, porous u-HA/PdlLA cylinders containing or lacking BMA were implanted in rabbit muscles. They were retrieved 4, 8, and 12 weeks after implantation, and ectopic bone formation was histologically evaluated. In experiment 2, 48 rabbits underwent PLF with 1 of 4 bone grafts: autogenous bone (group 1); single-strip u-HA/PdlLA alone (group 2); morselized u-HA/PdlLA + BMA (group 3); or single-strip u-HA/PdlLA + BMA (group 4). After 12 weeks, fusion was assessed by manual palpation, microcomputed tomography, mechanical tests, and histologic examination. In experiment 1, ectopic bone formation was observed in BMA-loaded u-HA/PdlLA, and the new bone area increased until 12 weeks after implantation. In experiment 2, the fusion rates in groups 1, 2, 3, and 4 were 58.3%, 16.7%, 66.7%, and 91.7%, respectively, as determined by manual palpation, and 66.7%, 16.7%, 75.0%, and 91.7%, respectively, as determined by microcomputed tomography. The mechanical strength was significantly greater in group 4 than in the other groups (P < 0.05). Conclusion. Our results indicate that BMA-loaded porous μ-HA/PdlLA is an effective alternative to autogenous bone grafts. The structure and composition of porous u-HA/PdlLA render it an effective

  9. Electronic Properties of Low-Dimensional Materials Under Periodic Potential

    NASA Astrophysics Data System (ADS)

    Jamei, Mehdi

    In the quest for the further miniaturization of electronic devices, numerous fabrication techniques have been developed. The semiconductor industry has been able to manifest miniaturization in highly complex and ultra low-power integrated circuits and devices, transforming almost every aspect of our lives. However, we may have come very close to the end of this trend. While advanced machines and techniques may be able to overcome technological barriers, theoretical and fundamental barriers are inherent to the top-down miniaturization approach and cannot be circumvented. As a result, the need for novel and natural alternatives to replace old materials is valued now more than ever. Fortunately, there exists a large group of materials that essentially has low-dimensional (quasi-one- or quasi-two-dimensional) structures. Graphene, a two-dimensional form of carbon, which has attracted a lot of attention in recent years, is a perfect example of a prime material from this group. Niobium tri-selenide (NbSe3), from a family of trichalcogenides, has a highly anisotropic structure and electrical conductivity. At sufficiently low temperatures, NbSe3 also exhibits two independent "sliding charge density waves"-- an exciting phenomenon, which could be altered by changing the overall size of the material. In NbSe3 (and Blue Bronze K0.3MoO3 which has a similar structure and electrical behavior), the effect of a periodic potential could be seen in creating a charge density wave (CDW) that is incommensurate to the underlying lattice. The required periodic potential is provided by the crystal ions when ordered in a particular way. The consequence is a peculiar non-linear conductivity behavior, as well as a unique narrow-band noise spectrum. Theoretical and experimental studies have concluded that the dynamic properties of resulting CDW are directly related to the crystal impurity density, and other pinning potentials. Therefore, reducing the overall size of the crystal could

  10. Compositional effects of organic material in HC potential assessment

    NASA Astrophysics Data System (ADS)

    Luo, W. P.; Tsai, L. Y.

    2015-12-01

    Studies of petroleum system is the main theme of hydrocarbon potential assessment, in which the characteristics of source rock is especially worth noticed. In recent years, besides the growth of conventional hydrocarbon resources being rapidly utilized, the exploration of unconventional deposits is getting more and more important. Since Taiwan has a strong energy demand and still highly relied on imported fossil fuel, the development of unconventional gas resources needs to be considered. This research discussed the relationship among characteristics and thermal maturity of different organic material versus their hydrocarbon potential. In order to compare the compositional effects from different organic material, torbanites from Huangxian basin, China and Miocene humic coal from Chuhuangkeng Anticline (one of the most productive oil and gas fields), Taiwan were examined and compared. Torbanites from China had relatively low maturation with vitrinite reflectance 0.38~0.51%, whereas the maturation of humic coal from Chuhuangkeng Anticline are a little bit higher with vitrinite reflectance 0.55~0.6%, plus some methane explored. Methods of study include petrographic analysis, vitrinite reflectance measurement (Ro%), Rock-Eval pyrolysis, and other geochemical parameters. The conclusions were derived after comparing experimental results and the regional geologic information of samples studied. In conclude, sample from China is type I kerogen, and its organic matter is mostly algae, whereas the humic coal sample from Taiwan belongs to type III kerogen. The analytic results indicate that the characteristics organic matters affect their maturity. Even though the thermal history and depositional environments are different in Taiwan and China, their organic micelles still exhibit a similar trend in the process of coalification. The role of maceral composition played in HC potential needs to be considered in future shale gas exploration.

  11. Microwave-assisted extraction of total bioactive saponin fraction from Gymnema sylvestre with reference to gymnemagenin: a potential biomarker.

    PubMed

    Mandal, Vivekananda; Dewanjee, Saikat; Mandal, Subhash C

    2009-01-01

    To develop a fast and ecofriendly microwave assisted extraction (MAE) technique for the effective and exhaustive extraction of gymnemagenin as an indicative biomarker for the quality control of Gymnema sylvestre. Several extraction parameters such as microwave power, extraction time, solvent composition, pre-leaching time, loading ratio and extraction cycle were studied for the determination of the optimum extraction condition. Scanning electron micrographs were obtained to elucidate the mechanism of extraction. The final optimum extraction conditions as obtained from the study were: 40% microwave power, 6 min irradiation time, 85% v/v methanol as the extraction solvent, 15 min pre-leaching time and 25 : 1 (mL/g) as the solvent-to-material loading ratio. The proposed extraction technique produced a maximum yield of 4.3% w/w gymnemagenin in 6 min which was 1.3, 2.5 and 1.95 times more efficient than 6 h of heat reflux, 24 h of maceration and stirring extraction, respectively. A synergistic heat and mass transfer theory was also proposed to support the extraction mechanism. Comparison with conventional extraction methods revealed that MAE could save considerable amounts of time and energy, whilst the reduction of volume of organic solvent consumed provides an ecofriendly feature.

  12. Screening of new bioactive materials from microbial extracts of soil microorganism (I). Antimicrobial activity from 200 samples using microdilution assay.

    PubMed

    Jung, S O; Kim, J; Chang, I M; Ryu, J C

    1998-06-01

    The microdilution assay recommended by NCCLS (National Committee for Clinical Laboratory Standards) is one of the standardized methods of antibiotic susceptibility test. This method has been widely used clinically to obtain MIC values of antibiotics on pathogenic microorganisms. It is more convenient, rapid and simple to test many samples than other test methods such as agar diffusion assay and broth macrodilution assay. The screening of antimicrobial agents from microbial extracts is too laborious in its process. Therefore, a number of screening methods having more simple procedure have been developed. In our laboratory, we applied microdilution assay for screening the antimicrobial agents. This assay showed dose-response results and was more sensitive than disc diffusion assay in our system. We tested 200 samples of microbial extracts originated from 100 microbial strains and selected several samples as potential candidates. In this report, we show that the microdilution assay is more convenient method in screening of antibiotic susceptibility than those previously reported.

  13. [Dietary bioactive compounds with potential in preventing pathologies related with overweight and obesity;biologically active peptides].

    PubMed

    Herrera Chalé, Francisco; Betancur Ancona, David; Segura Campos, Maira Rubi

    2014-01-01

    Overweight and obesity are risk factors for noncommunicable diseases such as cardiovascular diseases, diabetes and some types of cancer. The risk for these noncommunicable diseases increase with the increase in body mass index. Dietary proteins are known to carry a wide range of nutritional, functional and biological properties. Nutritionally, the proteins are a source of energy and amino acids, which are essential for growth and maintenance. Functionally, the proteins contribute to the physicochemical and sensory properties of various protein-rich foods. Furthermore, many dietary proteins possess specific biological properties which make these components potential ingredients of functional or health-promoting foods. Many of these properties are attributed to physiologically active peptides encrypted in protein molecules. This paper reviews antihypertensive, antithrombotic, hypocholesterolemic, hypoglycemic and hypolipidemic peptides originating from different sources and hydrolysis of proteins.

  14. Higher diet-dependent renal acid load associates with higher glucocorticoid secretion and potentially bioactive free glucocorticoids in healthy children.

    PubMed

    Esche, Jonas; Shi, Lijie; Sánchez-Guijo, Alberto; Hartmann, Michaela F; Wudy, Stefan A; Remer, Thomas

    2016-08-01

    Metabolic acidosis induces elevated glucocorticoid (GC) levels. However, the influence of less strong daily acid loads on GCs is largely unexplored. To investigate this, we studied whether higher acid loads in children, fully within the normal range of habitual diets, associate with endogenous GCs. In a specific quasi-experimental design, we examined 200 6- to 10-year-old healthy participants of the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study equally divided to either high or low 24-hour renal net acid excretion. Major urinary GC metabolites were analyzed by gas chromatography-mass spectrometry to assess daily adrenal GC secretion and metabolites of tissue cortisol catabolism (6β-hydroxycortisol and 20α-dihydrocortisol). Liquid chromatography-mass spectrometry was used to quantify urinary free cortisol and cortisone. After confounder adjustment, significant positive associations were unmasked for urinary potential renal acid load and net acid excretion with adrenal GC secretion, free cortisone, free cortisone plus cortisol, 6β-hydroxycortisol, and 20α-dihydrocortisol. An inverse association emerged for an enzymatic marker (5β-reductase) of irreversible GC inactivation. Our data suggest that existing moderate elevations in diet-dependent acid loads suffice to raise GCs and affect cortisol metabolism. Thus, potential detrimental effects of high acid loading appear to be mediated, in part, by increased GC activity via increased GC secretion and/or reduced GC inactivation. Higher cortisone levels, directly available for intracrine activation to cortisol may play a special role. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  15. Molecular profiling and bioactive potential of an endophytic fungus Aspergillus sulphureus isolated from Sida acuta: a medicinal plant.

    PubMed

    Murali, M; Mahendra, C; Hema, P; Rajashekar, N; Nataraju, A; Sudarshana, M S; Amruthesh, K N

    2017-12-01

    Sida acuta Burm.f. (Malvaceae) extracts are reported to have applications against malaria, diuretic, antipyretic, nervous and urinary diseases. No fungal endophytes of S. acuta are reported. Isolation, identification and evaluation of antibacterial, antioxidant, anticancer and haemolytic potential of fungal endophytes from the ethnomedcinal plant S. acuta. Sida acuta stem segments were placed on PDA medium to isolate endophytic fungi. The fungus was identified by genomic DNA analysis and phylogenetic tree was constructed using ITS sequences (GenBank) to confirm species. The antibacterial efficacy of Aspergillus sulphureus MME12 ethyl acetate extract was tested against Gram-positive and Gram-negative pathogenic bacteria. DPPH free radical scavenging activity, anticancer and DNA fragmentation against EAC cells, and direct haemolytic activity (100-500 μg/mL) using human erythrocytes were determined. The ethyl acetate extract of A. sulphureus (Fresen.) Wehmer (Trichocomaceae) demonstrated significant antibacterial potential against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Salmonella typhi compared to streptomycin. MIC against test pathogens was in the range of 15.6-62.5 μg/mL. The antioxidant results revealed significant RSA from 12.43% to 62.02% (IC50 = 350.4 μg/mL, p ≤ 0.05). MME12 offered considerable inhibition of EAC proliferation (23% to 84%, IC50 = 216.7 μg/mL, p ≤ 0.05) supported by DNA fragmentation studies. The extract also offered insignificant haemolysis (5.6%) compared to Triton X-100. A single endophytic fungus, A. sulphureus MME12 was isolated and identified using molecular profiling. The above-mentioned findings support the pharmacological application of A. sulphureus MME12 extract and demand for purification of the active principle(s).

  16. In vitro and in vivo antioxidant potentials of Alchornea floribunda leaf extract, fractions and isolated bioactive compounds

    PubMed Central

    Ajaghaku, Daniel Lotanna; Obasi, Okechukwu; Umeokoli, Blessing Ogechukwu; Ogbuatu, Peter; Nworu, Chukwuemeka Sylvester; Ilodigwe, Emmanuel Emeka; Okoye, Festus Basden Chiedu

    2017-01-01

    Objective: Alchornea floribunda leaves are widely used in ethnomedicine for the management of immuno-inflammatory disorders. We investigated the in vivo and in vitro antioxidant activity of the leaf extract, fractions and isolated compounds of A. floribunda. Materials and Methods: The ethyl acetate fraction of the methanol leaf extract was subjected to several chromatographic separations to isolate compounds 1-4. The structures of the isolated compounds were elucidated by a combination of 1D and 2D NMR and mass spectrometry. Oxidative stress was induced with carbon tetrachloride (CCl4). Further analysis on the isolated phenolic compounds were done using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and hydrogen peroxide scavenging activity tests. Results: The ethyl acetate fraction at 200 mg/kg produced significant (p<0.05) elevations of catalase enzyme activity and a significant (p<0.05) reduction in serum malondialdehyde. The chemical investigation of the ethyl acetate fraction led to the isolation of three flavans, (-) cathechin (1), (-) epicathechin (2), (+) epicathechin (3) and a flavanone, 2R, 3R dihydroquercitin (4). In hydrogen peroxide scavenging assay, (-) epicathechin exhibited an EC50 value of 8 μg/ml, similar to the standard ascorbic acid (EC50 = 8 μg/ml). (-) epicathechin showed scavenging of DPPH radical with EC50 value of 19 μg/ml while in the FRAP assay, it had EC50 value of 46 μg/ml which was lower than that of the standard, ascobic acid (EC50 = 66 μg/ml). Conclusion: The medicinal uses of A. floribunda may be due to the antioxidant activities of its phenolic compounds. PMID:28265550

  17. Developing a New Generation of Antimicrobial and Bioactive Dental Resins.

    PubMed

    Cheng, L; Zhang, K; Zhang, N; Melo, M A S; Weir, M D; Zhou, X D; Bai, Y X; Reynolds, M A; Xu, H H K

    2017-07-01

    Dental caries is prevalent, and secondary caries causes restoration failures. This article reviews recent studies on developing a new generation of bioactive resins with anticaries properties. Extensive effects were made to develop new antimicrobial composites, bonding agents, and other resins containing quaternary ammonium methacrylates to suppress plaque buildup and bacterial acid production. The effects of alkyl chain length and charge density and the antimicrobial mechanisms for chlorhexidine, nano-silver, quaternary ammonium methacrylates, and protein-repellent agents were discussed. Synergistic effects of contact-killing and protein-repellent properties were shown to yield the greatest biofilm-inhibition effects. The combination of antimicrobial, protein-repellent, and calcium phosphate nanoparticle remineralization was suggested to provide maximal anticaries effects. In addition, for use orally, cytotoxicity and biocompatibility were important considerations for the new bioactive materials. Furthermore, rather than kill all bacteria, it would be more desirable to modulate the oral biofilm compositions via bioactive resins to suppress cariogenic/pathogenic species and promote benign species. For widespread clinical use of the new antimicrobial and therapeutic materials, whether they would induce bacterial drug resistance needs to be determined, which requires further study. Nonetheless, the new generation of bioactive anticaries resins with therapeutic and biofilm acid-inhibiting properties has the potential to substantially benefit oral health.

  18. Immunomodulatory potential of a bioactive fraction from the leaves of Phyllostachys bambusoides (bamboo) in BALB/c mice

    PubMed Central

    Kumar, Sunil; Sharma, Gaurav; Sidiq, Tabasum; Khajuria, Anamika; Jain, Mahendra; Bhagwat, Deepak; Dhar, KL

    2014-01-01

    In order to evaluate the role of ethyl acetate fraction (PB-EtAC) obtained from the Phyllostachys bambusoides leaves in the modulation of immune responses, detailed studies were carried out using a panel of in vivo assays. Oral administration of PB-EtAC (50–200 mg/Kg) stimulated the IgM and IgG titre expressed in the form of haemagglutination antibody (HA) titre. Further, it elicited a dose related increase in the delayed type hypersensitivity reaction (DTH) after 24 and 48 h in BALB/c mice. Besides augmenting the humoral and cell mediated immune response, the concentration of cytokines (IFN-γ, IL-2, and IL-4) in serum with respect to T cell interactions also increased significantly. It also induced macrophage phagocytosis, and nitric oxide (NO) production which resulted in a high degree of protection against Candida albicans and carbon clearance. Moreover, the enhancement in CD4 and CD8 cell populations as revealed by flow cytometry. Taken together this in vivo and ex vivo preclinical data, our results suggested that PB-EtAC acts as an effective immunostimulator eliciting both Th1 and Th2 immune responses. We are reporting first time the immunostimulatory potential of P. bambusoides and it might be regarded as a biological response modifier. PMID:26417248

  19. Major Australian tropical fruits biodiversity: bioactive compounds and their bioactivities.

    PubMed

    Pierson, Jean T; Dietzgen, Ralf G; Shaw, Paul N; Roberts-Thomson, Sarah J; Monteith, Gregory R; Gidley, Michael J

    2012-03-01

    The plant kingdom harbours many diverse bioactive molecules of pharmacological relevance. Temperate fruits and vegetables have been highly studied in this regard, but there have been fewer studies of fruits and vegetables from the tropics. As global consumers demand and are prepared to pay for new appealing and exotic foods, tropical fruits are now being more intensively investigated. Polyphenols and major classes of compounds like flavonoids or carotenoids are ubiquitously present in these fruits, as they are in the temperate ones, but particular classes of compounds are unique to tropical fruits and other plant parts. Bioactivity studies of compounds specific to tropical fruit plants may lead to new drug discoveries, while the synergistic action of the wide range of diverse compounds contained in plant extracts underlies nutritional and health properties of tropical fruits and vegetables. The evidence for in vitro and animal bioactivities is a strong indicator of the pharmacological promise shown in tropical fruit plant biodiversity. In this review, we will discuss both the occurrence of potential bioactive compounds isolated and identified from a selection of tropical fruit plants of importance in Australia, as well as recent studies of bioactivity associated with such fruits and other fruit plant parts.

  20. Bare Bones of Bioactive Glass

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Paul Ducheyne, a principal investigator in the microgravity materials science program and head of the University of Pernsylvania's Center for Bioactive Materials and Tissue Engineering, is leading the trio as they use simulated microgravity to determine the optimal characteristics of tiny glass particles for growing bone tissue. The result could make possible a much broader range of synthetic bone-grafting applications. Even in normal gravity, bioactive glass particles enhance bone growth in laboratory tests with flat tissue cultures. Ducheyne and his team believe that using the bioactive microcarriers in a rotating bioreactor in microgravity will produce improved, three-dimensional tissue cultures. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and University of Pennsylvania Center for Bioactive Materials and Tissue Engineering.

  1. A potential bioactive wound dressing based on carboxymethyl cellulose/ZnO impregnated MCM-41 nanocomposite hydrogel.

    PubMed

    Rakhshaei, Rasul; Namazi, Hassan

    2017-04-01

    Lack of antibacterial activity, deficient water vapor and oxygen permeability, and insufficient mechanical properties are disadvantages of existing wound dressings. Hydrogels could absorb wound exudates due to their strong swelling ratio and give a cooling sensation and a wet environment. To overcome these shortcomings, flexible nanocomposite hydrogel films was prepared through combination of zinc oxide impregnated mesoporous silica (ZnO-MCM-41) as a nano drug carrier with carboxymethyl cellulose (CMC) hydrogel. Citric acid was used as cross linker to avoid the cytotoxicity of conventional cross linkers. The prepared nanocomposite hydrogel was characterized using X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Zeta potential and UV-vis spectroscopy. Results of swelling and erosion tests showed CMC/ZnO nanocomposite hydrogel disintegrated during the first hours of the test. Using MCM-41 as a substrate for ZnO nanoparticles solved this problem and the CMC/ZnO-MCM-41 showed a great improvement in tensile strength (12%), swelling (100%), erosion (53%) and gas permeability (500%) properties. Drug delivery and antibacterial properties of the nanocomposite hydrogel films studied using tetracycline (TC) as a broad spectrum antibiotic and showed a sustained TC release. This could efficiently decrease bandage exchange. Cytocompatibility of the nanocomposite hydrogel films has been analyzed in adipose tissue-derived stem cells (ADSCs) and results showed cytocompatibility of CMC/ZnO-MCM-41. Based on these results the prepared CMC nanocomposite hydrogel containing ZnO impregnated MCM-41, could serve as a kind of promising wound dressing with sustained drug delivery properties.

  2. Effect of lyophilization and storage temperature on the activity of salivaricin CRL 1328, a potential bioactive ingredient of a urogenital probiotic product.

    PubMed

    Vera Pingitore, Esteban; Bru, Elena; Elena Nader-Macías, Mar Iacutea

    2012-01-01

    Bacteriocins are antimicrobial peptides with potential applications as therapeutic agents for the treatment of microbial infections. The aim of this work was to investigate the effect of different protectors on the activity of salivaricin CRL1328, a bacteriocin produced by Lactobacillus salivarius CRL1328, during the lyophilization process and subsequent storage at different temperatures for 18 months using statistical models. Different protectors such as mannitol, Tween 80, polyethylene glycol 8000 (PEG), monosodium glutamate (MSG), reconstituted skim milk, sucrose and ascorbic acid were used for the lyophilization and storage of salivaricin. The biplot of principal component analysis was used for the interpretation of the interactions between the different factors studied. The antimicrobial activity of salivaricin was dependent mainly on temperature, and also on the time of storage and protector assayed. The stability of salivaricin was higher at -20°C and 4°C than 25°C and decreased during the time of storage; however, salivaricin was active after 18 months of storage at 25°C. Sucrose, mannitol plus sucrose, PEG plus sucrose and MSG were the most effective agents in protecting the bacteriocin during the lyophilization process. Effective maintenance of the activity of the bacteriocin was observed by storage with sucrose and ascorbic acid at -20°C as well as with PEG plus sucrose at 4°C and -20°C. The results obtained suggest that sucrose alone or combined with PEG can effectively maintain the activity of salivaricin during lyophilization and storage. This study provides useful information for the potential application of salivaricin as a bioactive principle for a pharmaceutical formulation.

  3. A potential insect growth regulator for cockroach control: design, synthesis and bioactivity of N-terminal-modified allatostatin analogues.

    PubMed

    Wu, Xiaoqing; Wang, Meizi; Huang, Juan; Zhang, Li; Zhang, Zhe; Ling, Yun; Yang, Xinling; Tobe, Stephen S

    2017-03-01

    The FGLa-allatostatins (ASTs) are a family of neuropeptides that can inhibit juvenile hormone biosynthesis by the corpora allata (CA) in vitro, and therefore they are regarded as insect growth regulator (IGR) candidates for pest control. In our previous studies, an AST mimic, H17, was found to have a significant effect on JH biosynthesis by cockroach CA, both in vitro and in vivo. To discover new potential mimics and explore the substituent effect on the inhibition of JH biosynthesis, 30 analogues, modified with various substituents on the benzene ring at the N-terminus of lead compound H17, were designed and synthesised. Their bioactivity in inhibiting JH biosynthesis by the CA of Diploptera punctata and the potency of M9, M10 and M11 in activation of Dippu-AstR were evaluated. All the analogues showed an effect on JH biosynthesis by CA in vitro. M9, M10 and M11 can activate the Dippu-AstR, albeit with much lower potency than that of AST 1. M11 also exhibited improved in vitro activity (IC50 6.98 nm) in comparison with the lead compound H17 (IC50 29.5 nm). In particular, M11 displayed good in vivo activity in inhibiting JH biosynthesis and basal oocyte growth. The structure-activity relationship studies suggest that different positions of substituents on the benzene ring of the cinnamic acid can lead to different activities. The para-substitution on the benzene ring plays an important role in inhibiting JH biosynthesis in vitro. Moreover, M11 is considered to be a potential IGR for cockroach control. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  4. RVNRL a potential material in latex dipped products manufacturing

    NASA Astrophysics Data System (ADS)

    Zin, Wan Manshol bin W.; Mohid, Norjanah; Razali, Meor Yahaya

    1995-09-01

    Preparation of radiation vulcanised natural rubber latex (RVNRL) using n-butyl acrylate as the sensitiser had been upgraded from a small scale to a bigger scale of about 500 kilograms per batch. Improvement on the physical properties of its vulcanisátes was observed. The tensile strength was determined to be about 28 MPa and the elongation at break of about 1000%. Despite its low ammonia content, about 0.4%, there was no negative effect detected neither on its alkalinity nor its stability. Upon incineration the film vulcanisate gave an ash residue as low as 0.7%. The sulphur content in the form of sulphate and sulphide were 0.11 mg per litre and < 0.001 mg per litre respectively. These properties plus other advantages discussed elsewhere make RVNRL a potential material for natural rubber latex dipped products manufacturing to suit the current needs.

  5. Geopolymers as potential repair material in tiles conservation

    NASA Astrophysics Data System (ADS)

    Geraldes, Catarina F. M.; Lima, Augusta M.; Delgado-Rodrigues, José; Mimoso, João Manuel; Pereira, Sílvia R. M.

    2016-03-01

    The restoration materials currently used to fill gaps in historical architectural tiles (e.g. lime or organic resin pastes) usually show serious drawbacks in terms of compatibility, effectiveness or durability. The existing solutions do not fully protect Portuguese faïence tiles ( azulejos) in outdoor conditions and frequently result in further deterioration. Geopolymers can be a potential solution for tile lacunae infill, given the chemical-mineralogical similitude to the ceramic body, and also the durability and versatile range of physical properties that can be obtained through the manipulation of their formulation and curing conditions. This work presents and discusses the viability of the use of geopolymeric pastes to fill lacunae in tiles or to act as "cold" cast ceramic tile surrogates reproducing missing tile fragments. The formulation of geopolymers, namely the type of activators, the alumino-silicate source, the quantity of water required for adequate workability and curing conditions, was studied. The need for post-curing desalination was also considered envisaging their application in the restoration of outdoor historical architectural tiles frequently exposed to adverse environmental conditions. The possible advantages and disadvantages of the use of geopolymers in the conservation of tiles are also discussed. The results obtained reveal that geopolymers pastes are a promising material for the restoration of tiles, when compared to other solutions currently in use.

  6. Mechanical model testing of rebreathing potential in infant bedding materials

    PubMed Central

    Carleton, J.; Donoghue, A.; Porter, W.

    1998-01-01

    Rebreathing of expired air may be a lethal hazard for prone sleeping infants. This paper describes a mechanical model to simulate infant breathing, and examines the effects of bedding on exhaled air retention. Under simulated rebreathing conditions, the model allows the monitoring of raised carbon dioxide (CO2) inside an artificial lung-trachea system. Resulting levels of CO2 (although probably exaggerated in the mechanical model compared with an infant, due to the model's fixed breathing rate and volume) suggest that common bedding materials vary widely in inherent rebreathing potential. In face down tests, maximum airway CO2 ranged from less than 5% on sheets and waterproof mattresses to over 25% on sheepskins, bean bag cushions, and some pillows and comforters. Concentrations of CO2 decreased with increasing head angle of the doll, away from the face down position. Recreations of 29infant death scenes also showed large CO2 increases on some bedding materials, suggesting these infants could have died while rebreathing.

 PMID:9623394

  7. Potential active materials for photo-supercapacitor: A review

    NASA Astrophysics Data System (ADS)

    Ng, C. H.; Lim, H. N.; Hayase, S.; Harrison, I.; Pandikumar, A.; Huang, N. M.

    2015-11-01

    The need for an endless renewable energy supply, typically through the utilization of solar energy in most applications and systems, has driven the expansion, versatility, and diversification of marketed energy storage devices. Energy storage devices such as hybridized dye-sensitized solar cell (DSSC)-capacitors and DSSC-supercapacitors have been invented for energy reservation. The evolution and vast improvement of these devices in terms of their efficiencies and flexibilities have further sparked the invention of the photo-supercapacitor. The idea of coupling a DSSC and supercapacitor as a complete energy conversion and storage device arose because the solar energy absorbed by dye molecules can be efficiently transferred and converted to electrical energy by adopting a supercapacitor as the energy delivery system. The conversion efficiency of a photo-supercapacitor is mainly dependent on the use of active materials during its fabrication. The performances of the dye, photoactive metal oxide, counter electrode, redox electrolyte, and conducting polymer are the primary factors contributing to high-energy-efficient conversion, which enhances the performance and shelf-life of a photo-supercapacitor. Moreover, the introduction of compact layer as a primary adherent film has been earmarked as an effort in enhancing power conversion efficiency of solar cell. Additionally, the development of electrolyte-free solar cell such as the invention of hole-conductor or perovskite solar cell is currently being explored extensively. This paper reviews and analyzes the potential active materials for a photo-supercapacitor to enhance the conversion and storage efficiencies.

  8. Thioborates: potential nonlinear optical materials with rich structural chemistry.

    PubMed

    Lian, Yu-Kun; Wu, Li-Ming; Chen, Ling

    2017-03-27

    Nonlinear optical (NLO) crystal materials with good performance are urgently needed. Various compounds have been explored to date. Metal chalcogenides and borates are common sources of potential NLO materials with desirable properties, particularly in the IR and UV regions, respectively. However, these two types of crystals have their specific drawbacks. Thioborates, as an emerging system, have unique advantages by combining the merits of borates and sulfides, i.e., the high laser damage thresholds and rich structural diversity of borates with large optical nonlinearity and the favorable transparency range of sulfides. However, only a limited number of thioborates are known. This paper summarizes the known thioborates according to structural motifs that range from zero-dimension to three-dimension, most of which are formed by sharing corners of the basic building units (BS3)(3-) and (BS4)(5-). Although nearly one-third of the known thioborates are noncentrosymmetric, most of their properties, especially their NLO behaviors, are unexplored. Further attempts and additional investigations are required with respect to design syntheses, property improvements and micro-mechanism studies.

  9. Bone regeneration in 3D printing bioactive ceramic scaffolds with improved tissue/material interface pore architecture in thin-wall bone defect.

    PubMed

    Shao, Huifeng; Ke, Xiurong; Liu, An; Sun, Miao; He, Yong; Yang, Xianyan; Fu, Jianzhong; Liu, Yanming; Zhang, Lei; Yang, Guojing; Xu, Sanzhong; Gou, Zhongru

    2017-04-12

    Three-dimensional (3D) printing bioactive ceramics have demonstrated alternative approaches to bone tissue repair, but an optimized materials system for improving the recruitment of host osteogenic cells into the bone defect and enhancing targeted repair of the thin-wall craniomaxillofacial defects remains elusive. Herein we systematically evaluated the role of side-wall pore architecture in the direct-ink-writing bioceramic scaffolds on mechanical properties and osteogenic capacity in rabbit calvarial defects. The pure calcium silicate (CSi) and dilute Mg-doped CSi (CSi-Mg6) scaffolds with different layer thickness and macropore sizes were prepared by varying the layer deposition mode from single-layer printing (SLP) to double-layer printing (DLP) and then by undergoing one-, or two-step sintering. It was found that the dilute Mg doping and/or two-step sintering schedule was especially beneficial for improving the compressive strength (∼25-104 MPa) and flexural strength (∼6-18 MPa) of the Ca-silicate scaffolds. The histological analysis for the calvarial bone specimens in vivo revealed that the SLP scaffolds had a high osteoconduction at the early stage (4 weeks) but the DLP scaffolds displayed a higher osteogenic capacity for a long time stage (8-12 weeks). Although the DLP CSi scaffolds displayed somewhat higher osteogenic capacity at 8 and 12 weeks, the DLP CSi-Mg6 scaffolds with excellent fracture resistance also showed appreciable new bone tissue ingrowth. These findings demonstrate that the side-wall pore architecture in 3D printed bioceramic scaffolds is required to optimize for bone repair in calvarial bone defects, and especially the Mg doping wollastontie is promising for 3D printing thin-wall porous scaffolds for craniomaxillofacial bone defect treatment.

  10. Evaluation of allelopathic potential and quantification of momilactone A,B from rice hull extracts and assessment of inhibitory bioactivity on paddy field weeds.

    PubMed

    Chung, Ill Min; Kim, Jung Tae; Kim, Seung-Hyun

    2006-04-05

    Rice (Oryza sativa L.) hull extracts were used in a bioassay to evaluate the allelopathic potential of rice on the germination and growth of barnyard grass (Echinochloa crus-galli P. Beauv. var. oryzicola Ohwi), to quantify momilactone A and B levels in rice hull germplasm and to assess the inhibitory bioactivity of momilactone A and B as a potential natural source of herbicide for weed control in paddy fields. Four varieties of weeds including E. crus-galli P. Beauv. var. oryzicola Ohwi, Monochoria vaginalis var. plantaginea, Scirpus juncoides, and Eleocharis kuroguwai were tested in the paddy field. Of 99 rice varieties, the top five including Noindari exhibited inhibition effects greater than 50% in average inhibition of dry weight (AIDW). Noindari among them exerted the strongest effect (55.6%). The next five in the ranking exhibited inhibition effects of greater than 40%. Also, 46 varieties had inhibition effects between 20 and 40%, and 29 varieties had inhibition effects greater than 10%. Fourteen varieties had very low inhibitory effects (less than 10%), the lowest of which was Heunbe (4.7%). These varieties showed a mean inhibition of 19.8% for germination rate (GR), 9.9% for germination percentage (GP), 16.6% for leaf dry weight (LDW), 38.9% for straw dry weight (SDW), and 26.8% for root dry weight (RDW). Rice varieties were classified into six categories based on their total momilactones (TMs) (momilactone A + momilactone B). The highest level of momilactone A was found in the Baekna rice variety (34.7 microg g(-1)), and Baekgwangok contained the highest level of momilactone B (37.8 microg g(-1)). In allelopathic potential with genetic properties and morphological characteristics, the total inhibition rate (TIR) was 18.3% for Korean rice varieties, 19.0% for middle maturing varieties, 17.8% for colorless hull varieties, 18.3% for awn varieties, and 19.0% for colorless awn varieties. In addition, Korean varieties showed higher TMs (4.5 microg g(-1)) as

  11. The future of bioactive ceramics.

    PubMed

    Hench, Larry L

    2015-02-01

    Two important worldwide needs must be satisfied in the future; (1) treatment of the deteriorating health of an aging population and, (2) decreasing healthcare costs to meet the needs of an increased population. The ethical and economic dilemma is how to achieve equality in quality of care while at the same time decreasing cost of care for an ever-expanding number of people. The limited lifetime of prosthetic devices made from first-generation nearly inert biomaterials requires new approaches to meet these two large needs. This paper advises an expanded emphasis on: (1) regeneration of tissues and (2) prevention of tissue deterioration to meet this growing need. Innovative use of bioactive ceramics with genetic control of in situ tissue responses offers the potential to achieve both tissue regeneration and prevention. Clinical success of use of bioactive glass for bone regeneration is evidence that this concept works. Likewise the use of micron sized bioactive glass powders in a dentifrice for re-mineralization of teeth provides evidence that prevention of tissue deterioration is also possible. This opinion paper outlines clinical needs that could be met by innovative use of bioactive glasses and ceramics in the near future; including: regeneration of skeletal tissues that is patient specific and genetic based, load-bearing bioactive glass-ceramics for skeletal and ligament and tendon repair, repair and regeneration of soft tissues, and rapid low-cost analysis of human cell-biomaterial interactions leading to patient specific diagnoses and treatments using molecularly tailored bioceramics.

  12. Sol-gel derived porous bioactive nanocomposites: Synthesis and in vitro bioactivity

    NASA Astrophysics Data System (ADS)

    Shankhwar, Nisha; Kothiyal, G. P.; Srinivasan, A.

    2013-06-01

    Porous bioactive composites consisting of SiO2-CaO-Na2O-P2O5 bioactive glass-ceramic and synthetic water soluble polymer Polyvinylpyrrolidone [PVP (C6H9NO)n, MW˜40000 g/mol] have been synthesized by sol-gel route. As-prepared polymeric composites were characterized by X-ray diffraction (XRD) technique. Two major bone mineral phases, viz., hydroxyapatite [Ca10(PO4)6(OH)2] and wollastonite [calcium silicate (CaSiO3)] have been identified in the XRD patterns of the composites. Presence of these bone minerals indicates the bioactive nature of the composites. In vitro bioactivity tests confirm bioactivity in the porous composites. The flexibility offered by these bioactive polymer composites is advantageous for its application as implant material.

  13. A potential material to cut down infection caused by application of artificial muscles.

    PubMed

    Wang, Jiang-Ning; Li, Xiao-Rong; Wang, De-Cheng

    2013-04-01

    Artificial muscles are so important that can be used to cure prosthetic limbs. A new kind of taurine Schiff base sodium was synthesized by a series of chemical reactions, which may be applied to strengthen antibacterial activity of artificial muscle. The bioactivity of this material was screened by cytotoxicity test, antibacterial test, and thermal gravity test and so on. All results told us that this material had low toxicity, high antibacterial activity and thermal stability. Combine our deep studies on pharmacological activity of the active material with our knowledge on artificial muscles; we want to know if we can put this material into the content of artificial muscle, in order to strengthen its antimicrobial activity, so that the pains of the patients who were applied artificial muscle would be relieved.

  14. Preparation and characterization of bioactive glass nanoparticles prepared by sol-gel for biomedical applications

    NASA Astrophysics Data System (ADS)

    Luz, Gisela M.; Mano, João F.

    2011-12-01

    Bioactive glass nanoparticles (BG-NPs), based on both ternary (SiO2-CaO-P2O5) and binary (SiO2-CaO) systems, were prepared via an optimized sol-gel method. The pH of preparation and the effect of heat treatment temperature were evaluated, as well as the effect of suppressing P in the bioactivity ability of the materials. The morphology and composition of the BG-NPs were studied using FTIR, XRD and SEM. The bioactive character of these materials was accessed in vitro by analyzing the ability for apatite formation onto the surface after being immersed in simulated body fluid (SBF). XRD, EDX and SEM were used to confirm the bioactivity of the materials. The BG-NP effect on cell metabolic activity was assessed by seeding L929 cells with their leachables, proving the non-cytotoxicity of the materials. Finally the most bioactive BG-NPs developed (ternary system prepared at pH 11.5 and treated at 700 °C) were successfully combined with chitosan in the production of biomimetic nanocomposite osteoconductive membranes that could have the potential to be used in guided tissue regeneration.

  15. Production and bioactivity of pectic oligosaccharides from fruit and vegetable biomass

    USDA-ARS?s Scientific Manuscript database

    Pectin is abundant in various agro-industrial bio-resources such as citrus peel, apple pomace, cranberry pulp and sugar beet pulp. These materials can therefore be considered as a source of potential bioactive pectic oligosaccharides. This chapter reviews the various extraction and purification meth...

  16. The SRAP based molecular diversity related to antifungal and antioxidant bioactive constituents for biocontrol potentials of Trichoderma against Sclerotium rolfsii Scc.

    PubMed

    Hirpara, Darshna G; Gajera, H P; Bhimani, R D; Golakiya, B A

    2016-08-01

    The study was performed to examine 11 isolates of Trichoderma for their bio-control potentials against Sclerotium rolfsii Sacc. causing stem rot in groundnut. The antagonists Trichoderma were subjected to sequence related amplified polymorphism (SRAP) based molecular diversity analysis and compared with their hardness to S. rolfsii with respect to secretary antifungal and antioxidant profile. T. virens NBAII Tvs 12 evident highest (87.91 %) growth inhibition of test pathogen followed by T. koningii MTCC 796 (67.03 %) at 7 days after inoculation (DAI). Microscopic study confirmed biocontrol mechanism as mycoparasitism for Tvs 12 and antibiosis for MTCC 796. The growth inhibition of test pathogen was significantly negatively correlated with sclerotia formation and lipid peroxidation during antagonism due to release of secretary bioactive antioxidants by antagonists to terminate oxidative burst generated by S. rolfsii and causing inhibition of sclerotium formation. The GC-MS profile identified antifungal and antioxidant constituents hexadecane, 1,2-benzenedicarboxylic acid, mono (2-ethylhexyl) ester, 1-hexadecanesulfonyl chloride, and octadecane in potent antagonists Tvs 12; and nonacosane and octadecane in MTCC 796 along with two novel compounds 1-pentadecene and 1-heneicosyl formate for biocontrol activity. Molecular diversity of Trichoderma isolates associated with antagonistic activity was assessed by SRAP markers. The 115 primer combinations generate total 1328 amplified products of which, 1095 are shared polymorphic and 199 are unique polymorphic. The 15 SRAP combinations produced 18 bands to diagnose best antagonist Tvs 12 and 13 SRAP combinations generated 19 unique bands for identification of MTCC 796. The mycoparasitic antagonist Tvs 12 would be the best antagonist and released unique antifungal and antioxidant constituents to combat pathogen infection. The SRAP based genetic diversity indicates Tvs12 strain clustered with T. viride NBAII Tv23 and shared

  17. Cytotoxicity and osteogenic potential of silicate calcium cements as potential protective materials for pulpal revascularization.

    PubMed

    Bortoluzzi, Eduardo A; Niu, Li-Na; Palani, Chithra D; El-Awady, Ahmed R; Hammond, Barry D; Pei, Dan-Dan; Tian, Fu-Cong; Cutler, Christopher W; Pashley, David H; Tay, Franklin R

    2015-12-01

    In pulpal revascularization, a protective material is placed coronal to the blood clot to prevent recontamination and to facilitate osteogenic differentiation of mesenchymal stem cells to produce new dental tissues. Although mineral trioxide aggregate (MTA) has been the material of choice for clot protection, it is easily displaced into the clot during condensation. The present study evaluated the effects of recently introduced calcium silicate cements (Biodentine and TheraCal LC) on the viability and osteogenic differentiation of human dental pulp stem cells (hDPSCs) by comparing with MTA Angelus. Cell viability was assessed using XTT assay and flow cytometry. The osteogenic potential of hDPSCs exposed to calcium silicate cements was examined using qRT-PCR for osteogenic gene expressions, alkaline phosphatase enzyme activity, Alizarin red S staining and transmission electron microscopy of extracellular calcium deposits. Parametric statistical methods were employed for analyses of significant difference among groups, with α=0.05. The cytotoxic effects of Biodentine and TheraCal LC on hDPSCs were time- and concentration-dependent. Osteogenic differentiation of hDPSCs was enhanced after exposure to Biodentine that was depleted of its cytotoxic components. This effect was less readily observed in hDPSCs exposed to TheraCal LC, although both cements supported extracellular mineralization better than the positive control (zinc oxide-eugenol-based cement). A favorable tissue response is anticipated to occur with the use of Biodentine as a blood clot-protecting material for pulpal revascularization. Further investigations with the use of in vivo animal models are required to validate the potential adverse biological effects of TheraCal LC on hDPSCs. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  18. Bare Bones of Bioactive Glass

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Paul Ducheyne, a principal investigator in the microgravity materials science program and head of the University of Pernsylvania's Center for Bioactive Materials and Tissue Engineering, is leading the trio as they use simulated microgravity to determine the optimal characteristics of tiny glass particles for growing bone tissue. The result could make possible a much broader range of synthetic bone-grafting applications. Bioactive glass particles (left) with a microporous surface (right) are widely accepted as a synthetic material for periodontal procedures. Using the particles to grow three-dimensional tissue cultures may one day result in developing an improved, more rugged bone tissue that may be used to correct skeletal disorders and bone defects. The work is sponsored by NASA's Office of Biological and Physical Research.

  19. MR of ballistic materials: imaging artifacts and potential hazards.

    PubMed

    Smith, A S; Hurst, G C; Duerk, J L; Diaz, P J

    1991-01-01

    The most common ballistic materials available in the urban setting were studied for their MR effects on deflection force, rotation, heating, and imaging artifacts at 1.5 T to determine the potential efficacy and safety for imaging patients with ballistic injuries. The 28 missiles tested covered the range of bullet types and materials suggested by the Cleveland Police Department. The deflection force was measured by the New method. Rotation was evaluated 30 min after bullets had been placed in a 10% (weight per weight) ballistic gelatin designed to simulate brain tissue, with the long axis of the bullet placed parallel and perpendicular to the Z axis of the magnet. Heating was measured with alcohol thermometers by imaging for 1 hr alternatively with gradient-echo and spin-echo sequences (RF absorption = 0.033 and 0.326 w/kg respectively). Image artifacts on routine sequences were evaluated. All the steel-containing bullets except for the Winchester armor-piercing 38 caliber exhibited deflection. A nonsteel 7.38-mm Mauser also deflected. Deflection range was 514 to 15,504 dynes. Rotation occurred when the bullets were not parallel to the Z axis. Temperature changes were not significant. Deflecting projectiles resulted in obliteration of the image. The artifacts from other projectiles were small but varied by content. The artifact of the Winchester armor-piercing 38-caliber bullet was similar to those without steel. Bullets that contain steel or ferromagnetic contaminates such as nickel can be rotated within the MR unit.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Topological insulators/superconductors: Potential future electronic materials

    SciTech Connect

    Hor, Y. S.

    2014-03-05

    A new material called topological insulator has been discovered and becomes one of the fastest growing field in condensed matter physics. Topological insulator is a new quantum phase of matter which has Dirac-like conductivity on its surface, but bulk insulator through its interior. It is considered a challenging problem for the surface transport measurements because of dominant internal conductance due to imperfections of the existing crystals of topological insulators. By a proper method, the internal bulk conduction can be suppressed in a topological insulator, and permit the detection of the surface currents which is necessary for future fault-tolerant quantum computing applications. Doped topological insulators have depicted a large variety of bulk physical properties ranging from magnetic to superconducting behaviors. By chemical doping, a TI can change into a bulk superconductor. Nb{sub x}Bi{sub 2}Se{sub 3} is shown to be a superconductor with T{sub c} ∼ 3.2 K, which could be a potential candidate for a topological superconductor.

  1. Enhancing the Bioactivity of Yttria-Stabilized Tetragonal Zirconia Ceramics via Grain-Boundary Activation.

    PubMed

    Ke, Jinhuan; He, Fupo; Ye, Jiandong

    2017-05-17

    Yttria-stabilized tetragonal zirconia (Y-TZP) has been proposed as a potential dental implant because of its good biocompatibility, excellent mechanical properties, and distinctive aesthetic effect. However, Y-TZP cannot form chemical bonds with bone tissue because of its biological inertness, which affects the reliability and long-term efficacy of Y-TZP implants. In this study, to improve the bioactivity of Y-TZP ceramics while maintaining their good mechanical performance, Y-TZP was modified by grain-boundary activation via the infiltration of a bioactive glass (BG) sol into the surface layers of Y-TZP ceramics under different negative pressures (atmospheric pressure, -0.05 kPa, and -0.1 kPa), followed by gelling and sintering. The in vitro bioactivity, mechanical properties, and cell behavior of the Y-TZP with improved bioactivity were systematically investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), electron probe microanalysis (EPMA), and Raman spectroscopy. The results of the bioactivity test conducted by immersing Y-TZP in simulated body fluid (SBF) showed that a bonelike apatite layer was produced on the entire surface. The mechanical properties of the modified Y-TZP decreased as the negative pressure in the BG-infiltration process increased relative to those of the Y-TZP blank group. However, the samples infiltrated with the BG sol under -0.05 kPa and atmospheric pressure still retained good mechanical performance. The cell-culture results revealed that the bioactive surface modification of Y-TZP could promote cell adhesion and differentiation. The present work demonstrates that the bioactivity of Y-TZP can be enhanced by grain-boundary activation, and the bioactive Y-TZP is expected to be a potential candidate for use as a dental implant material.

  2. Polyethlyene glycol microgels to deliver bioactive nerve growth factor.

    PubMed

    Stukel, Jessica; Thompson, Susan; Simon, Laurent; Willits, Rebecca

    2015-02-01

    Delivery of bioactive molecules is a critical step in fabricating materials for regenerative medicine, yet, this step is particularly challenging in hydrated scaffolds such as hydrogels. Although bulk photocrosslinked poly(ethylene glycol) (PEG) hydrogels have been used for a variety of tissue engineering applications, their capability as drug delivery scaffolds has been limited due to undesirable release profiles and reduction in bioactivity of molecules. To solve these problems, this article presents the fabrication of degradable PEG microgels, which are micron-sized spherical hydrogels, to deliver bioactive nerve growth factor (NGF). NGF release and activity was measured after encapsulation in microgels formed from either 3 kDa or 6 kDa PEG to determine the role of hydrogel mesh size on release. Microgels formed from 6 kDa PEG were statistically larger and had a higher swelling ratio than 3 kDa PEG. The 6 kDa PEG microgels provided a Fickian release with a reduced burst effect and 3 kDa microgels provided anomalous release over ≥20 days. Regardless of molecular weight of PEG, NGF bioactivity was not significantly reduced compared to unprocessed NGF. These results demonstrate that microgels provide easy mechanisms to control the release while retaining the activity of growth factors. As this microgel-based delivery system can be injected at the site of nerve injury to promote nerve repair, the potential to deliver active growth factors in a controlled manner may reduce healing time for neural tissue engineering applications.

  3. Cytotoxicity and Osteogenic Potential of Silicate Calcium Cements as Potential Protective Materials for Pulpal Revascularization

    PubMed Central

    Bortoluzzi, Eduardo A.; Niu, Li-na; Palani, Chithra D.; El-Awady, Ahmed R.; Hammond, Barry D.; Pei, Dan-dan; Tian, Fu-cong; Cutler, Christopher W.; Pashley, David H.; Tay, Franklin R.

    2016-01-01

    Objectives In pulpal revascularization, a protective material is placed coronal to the blood clot to prevent recontamination and to facilitate osteogenic differentiation of mesenchynal stem cells to produce new dental tissues. Although mineral trioxide aggregate (MTA) has been the material of choice for clot protection, it is easily displaced into the clot during condensation. The present study evaluated the effects of recently-introduced calcium silicate cements (Biodentine and TheraCal LC) on the viability and osteogenic differentiation of human dental pulp stem cells (hDPSCs) by comparing with MTA Angelus. Methods Cell viability was assessed using XTT assay and flow cytometry. The osteogenic potential of hDPSCs exposed to calcium silicate cements was examined using qRT-PCR for osteogeic gene expressions, alkaline phosphatase enzyme activity, Alizarin red S staining and transmission electron microscopy of extracellular calcium deposits. Parametric statistical methods were employed for analyses of significant difference among groups, with α=0.05. Results The cytotoxic effects of Biodentine and TheraCal LC on hDPSCs were time- and concentration-dependent. Osteogenic differentiation of hDPSCs was enhanced after exposure to Biodentine that was depleted of its cytotoxic components. This effect was less readily observed in hDPSCs exposed to TheraCal LC, although both cements supported extracelluar mineralization better than the positive control (zinc oxide-eugenol–based cement). Significance A favorable tissue response is anticipated to occur with the use of Biodentine as a blood clot-protecting material for pulpal revascularizaiton. Further investigations with the use of in vivo animal models are required to validate the potential adverse biological effects of TheraCal LC on hDPSCs. PMID:26494267

  4. Biopolymeric hydrogels - nanostructured TiO2 hybrid materials as potential injectable scaffolds for bone regeneration.

    PubMed

    Zazakowny, Karolina; Lewandowska-Łańcucka, Joanna; Mastalska-Popławska, Joanna; Kamiński, Kamil; Kusior, Anna; Radecka, Marta; Nowakowska, Maria

    2016-12-01

    The present work aims at development of novel hybrid materials from genipin crosslinked collagen or collagen/chitosan hydrogels containing various types of TiO2 nanoparticles characterized with different anatase/rutile ratios. Collagen and chitosan were selected as hydrogel components since they are biopolymers being, like collagen, the major compound present in extracellular matrix or exhibit structural similarity to glycosaminoglycans, like chitosan. TiO2 nanoparticles were introduced to the hydrogel matrices to improve their mechanical properties as well as bioactivity. A series of twelve novel hybrid materials were prepared and their physicochemical, mechanical and biological properties were evaluated. It was found that TiO2 nanostructures introduced to the hydrogels have significant influence on the swelling properties of the synthesized hybrids and their impact is strongly dependent on the type of matrices. The surfaces of hybrid materials were found to be more hydrophilic than these of corresponding hydrogel matrix. It was also observed that, the storage modulus values of the hybrids based on collagen-chitosan hydrogel are comparable to these for plain hydrogels what indicates that the mechanical properties of the materials obtained are satisfactory for possible biomedical application. The in vitro cell culture studies have shown that prepared materials are biocompatible as they can support mitochondrial activity of MEFs as well as MG-63 cells. In vitro experiments performed under simulated body fluid (SBF) conditions have revealed that all studied TiO2 nanoparticles present in hydrogel matrices, regardless of anatase/rutile ratio, successfully induced formation of apatite-like structures. The hybrid materials developed here are promising candidates for preparation of bioactive, injectable scaffolds for tissue engineering.

  5. Technologies for Enhancement of Bioactive Components and Potential Health Benefits of Cereal and Cereal-Based Foods: Research Advances and Application Challenges.

    PubMed

    Saleh, Ahmed S M; Wang, Peng; Wang, Na; Yang, Shu; Xiao, Zhigang

    2017-08-28

    Cereal grains are a major source of human food and their production has steadily been increased during the last several decades to meet the demand of our increasing world population. The modernized society and the expansion of the cereal food industry created a need for highly efficient processing technologies, especially flour production. Earlier scientific research efforts have led to the invention of the modern steel roller mill, and the refined flour of wheat has become a basic component in most of cereal-based foods such as breads and pastries because of the unique functionality of wheat protein. On the other hand, epidemiological studies have found that consumption of whole cereal grains was health beneficial. The health benefit of whole cereal grain is attributed to the combined effects of micronutrients, phytochemicals, and dietary fibre, which are mainly located in the outer bran layer and the germ. However, the removal of bran and germ from cereal grains during polishing and milling results in refined flour and food products with lower bioactive compounds and dietary fibre contents than those from whole grain. Also, the level of bioactive compounds in cereal food is influenced by other food preparation procedures such as baking, cooking, extrusion, and puffing. Therefore, food scientists and nutritionists are searching for strategies and processing technologies to enhance the content and bioavailability of nutrients, bioactive compounds, and dietary fibre of cereal foods. The objective of this article was to review the research advances on technologies for the enhancement of bioactive compounds and dietary fibre contents of cereal and cereal-based foods. Bioactivities or biological effects of enhanced cereal and cereal-based foods are presented. Challenges facing the application of the proposed technologies in the food industry are also discussed.

  6. Bioactive glass efficacy in the periodontal healing of intrabony defects in monkeys.

    PubMed

    Villaça, José Henrique; Novaes, Arthur B; Souza, Sérgio Luís Scombatti de; Taba, Mario; Molina, Gustavo Otoboni; Carvalho, Teresa Lúcia Lamano

    2005-01-01

    The purpose of this study was the histomorphologic analysis of the efficacy of bioactive glass particles with a narrow size range (Biogran) in the periodontal healing of 2-wall intrabony defects in monkeys. The 2-wall defects were made in the mesial area of the left and right second premolars of four monkeys, filled with gutta-percha and, after 15 days, they were debrided and either naturally filled with coagulum (control) or implanted with bioactive glass (test). In the control sites, the junctional epithelium migrated up to the base of the defect. The presence of newly formed cementum was more significant in the test defects. Both control and test sites showed newly formed bone at the base of the defect. The test defects presented foci of newly formed bone around and within the glass particles localized in the middle third, distant from the defect walls. Histologic analysis showed that the 300- to 355-microm bioactive glass particles aided new periodontal insertion. In conclusion, the tested bioactive glass had better healing potential than debridement only. The graft material showed a promising inhibition of apical migration of the junctional epithelium and greater cementum deposition on the radicular surface of the intrabony defects. The replacement of bioactive glass particles by new bone occurred due not only to an osteoconductive property, but also to an osteostimulatory capacity. Future investigations should evaluate this potential comparatively or together with other grafting materials, regenerative techniques and biological modifiers, as well as assess the longitudinal stability of the new attachment.

  7. Biomimetic formation of apatite on the surface of porous gelatin/bioactive glass nanocomposite scaffolds

    NASA Astrophysics Data System (ADS)

    Mozafari, Masoud; Rabiee, Mohammad; Azami, Mahmoud; Maleknia, Saied

    2010-12-01

    There have been several attempts to combine bioactive glasses (BaGs) with biodegradable polymers to create a scaffold material with excellent biocompatibility, bioactivity, biodegradability and toughness. In the present study, the nanocomposite scaffolds with compositions based on gelatin (Gel) and BaG nanoparticles in the ternary SiO 2-CaO-P 2O 5 system were prepared. In vitro evaluations of the nanocomposite scaffolds were performed, and for investigating their bioactive capacity these scaffolds were soaked in a simulated body fluid (SBF) at different time intervals. The scaffolds showed significant enhancement in bioactivity within few days of immersion in SBF solution. The apatite formation at the surface of the nanocomposite samples confirmed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray powder diffraction (XRD) analyses. In vitro experiments with osteoblast cells indicated an appropriate penetration of the cells into the scaffold's pores, and also the continuous increase in cell aggregation on the bioactive scaffolds with increase in the incubation time demonstrated the ability of the scaffolds to support cell growth. The SEM observations revealed that the prepared scaffolds were porous with three dimensional (3D) and interconnected microstructure, pore size was 200-500 μm and the porosity was 72-86%. The nanocomposite scaffold made from Gel and BaG nanoparticles could be considered as a highly bioactive and potential bone tissue engineering implant.

  8. Phytochemical and Bioactive Potential of in vivo and in vitro Grown Plants of Centaurea ragusina L. - Detection of DNA/RNA Active Compounds in Plant Extracts via Thermal Denaturation and Circular Dichroism.

    PubMed

    Vujčić, Valerija; Radić Brkanac, Sandra; Radojčić Redovniković, Ivana; Ivanković, Siniša; Stojković, Ranko; Žilić, Irena; Radić Stojković, Marijana

    2017-07-25

    The phytochemical composition and biological activity of non-volatile components of Centaurea ragusina L. has not been studied previously. Our aim was to evaluate the phytochemical and bioactive potential (including interactions with polynucleotides) of C. ragusina L. depending on the origin of plant material (in vivo - leaves from natural habitats, ex vitro - leaves from plants acclimated from culture media, in vitro - leaves and calli from plants grown in culture media) and polarity of solvents used in extract preparation (80 and 96% ethanol and water combinations or single solvents). The polyphenol composition was determined by spectrophotometric and HPLC analysis. Biological activity of extracts was evaluated by following methods: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) methods for antioxidative activity, 2,3,5-triphenyl tetrazolium chloride (TTC) microdilution method for antibacterial activity, crystal-violet test for cytotoxic activity and thermal denaturation (TD) and circular dichroism (CD) for DNA/RNA interactions. Conditions for the most efficient polyphenol extraction were determined: the 80% ethanol/water solvent system was the most suitable for callus and leaf ex vitro samples and 80 or 96% ethanol for leaf in vivo samples. Significantly higher levels of chlorogenic acid and naringenin were detected in callus tissue than in vivo plant. Ethanolic extracts exhibited the significant antibacterial activity against Staphylococcus aureus ATCC 25923. DNA/RNA active compounds in plant extracts were detected by TD and CD methods. Callus tissue and ex vitro leaves represent a valuable source of polyphenols as in vivo leaves. TD and CD can be applied for detection of DNA/RNA active compounds in extracts from natural resources. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  9. Material Affordances: The Potential of Scrapbooks in the Composition Classroom

    ERIC Educational Resources Information Center

    Alexander, Kara Poe

    2013-01-01

    A multiliteracies pedagogy has renewed our interest in materiality, or how the physical text interacts with the author's choices and the context to contribute to the message, yet little attention has been paid to materiality in analog texts, such as the scrapbook, even though this medium contains affordances (capabilities and limitations) that…

  10. Oligopyrrole Macrocycles: Receptors and Chemosensors for Potentially Hazardous Materials

    PubMed Central

    2011-01-01

    Oligopyrroles represent a diverse class of molecular receptors that have been utilized in a growing number of applications. Recently, these systems have attracted interest as receptors and chemosensors for hazardous materials, including harmful anionic species, high-valent actinide cations, and nitroaromatic explosives. These versatile molecular receptors have been used to develop rudimentary colorimetric and fluorimetric assays for hazardous materials. PMID:21465591

  11. A new synthesis route to high surface area sol gel bioactive glass through alcohol washing: a preliminary study.

    PubMed

    Mukundan, Lakshmi M; Nirmal, Remya; Vaikkath, Dhanesh; Nair, Prabha D

    2013-01-01

    Bioactive glass is one of the widely used bone repair material due to its unique properties like osteoconductivity, osteoinductivity and biodegradability. In this study bioactive glass is prepared by the sol gel process and stabilized by a novel method that involves a solvent instead of the conventional calcinations process. This study represents the first attempt to use this method for the stabilization of bioactive glass. The bioactive glass stabilized by this ethanol washing process was characterized for its physicochemical and biomimetic property in comparison with similar composition of calcined bioactive glass. The compositional similarity of the two stabilized glass powders was confirmed by spectroscopic and thermogravimetric analysis. Other physicochemical characterizations together with the cell culture studies with L929 fibroblast cells and bone marrow mesenchymal stem cells proved that the stabilization was achieved with the retention of its inherent bioactive potential. However an increase in the surface area of the glass powder was obtained as a result of this ethanol washing process and this add up to the success of the study. Hence the present study exhibits a promising route for high surface area bioactive glass for increasing biomimicity.

  12. Study of the potential cytotoxicity of dental impression materials.

    PubMed

    Roberta, Tiozzo; Federico, Magagna; Federica, Boraldi; Antonietta, Croce Maria; Sergio, Bortolini; Ugo, Consolo

    2003-01-01

    The aim of this study was to assess the cytotoxicity of tow types of impression dental materials: polyethers (Impregum Penta, Permadyne Penta Heavy and Light) and vinyl polysiloxanes (Elite Mono Tray, Medium, Low viscosity and Elite H-D Putty). Their cytotoxic effects were studied by indirect and direct tests. The indirect tests were performed by incubating impression materials in serum free cell culture medium to prepare the soluble extracts. Balb/c 3T3 cells were incubated with extract dilutions (25, 50, 75 and 100%) for 24 h. The extracts of polyether materials caused a decrease of cellular viability, evaluated by light microscopy, by cell counting and by MTT test. The extracts of vinyl polysiloxanes materials induced a slight effect on cellular number and viability. The direct tests were performed by placing the impression materials in the centre of Petri dishes while Balb/c 3T3 were settling. The cellular proliferation was drastically reduced by polyethers and it was unaffected by the presence of vinyl polysiloxanes. These results show that: (a) the polyether materials are more toxic than vinyl polysiloxanes in our experimental conditions, (b) the impression materials are cytotoxic to the same degree in all assay methods.

  13. Antileishmanial activity of compounds produced by endophytic fungi derived from medicinal plant Vernonia polyanthes and their potential as source of bioactive substances.

    PubMed

    do Nascimento, Adriana M; Soares, Mateus Gonçalves; da Silva Torchelsen, Fernanda K V; de Araujo, Jorge A Viana; Lage, Paula S; Duarte, Mariana C; Andrade, Pedro H R; Ribeiro, Tatiana G; Coelho, Eduardo A F; do Nascimento, Andréa M

    2015-11-01

    The purpose of this work was to evaluate the antileishmanial activity of endophytic fungi isolated from leaves of Vernonia polyanthes plant and their prospective use in the discovery of bioactive compounds. Sixteen endophytes were isolated by using potato dextrose agar medium and submitted to cultivation in rice medium. The fungal cultures were extracted with ethanol and used as crude extracts for testing their antileishmanial activity. The most active ethanol extract was obtained from P2-F3 strain, which was identified as Cochliobolus sativus by ITS rRNA gene sequence data. Followed by a bioassay-guided fractionation, the cochlioquinone A, isocochlioquinone A and anhydrocochlioquinone A compounds were isolated from the crude extracts and demonstrated to inhibit the parasites. From the present work, it is possible to conclude that endophytic fungi derived from medicinal plant V. polyanthes may be considered promising source for the discovery of bioactive compounds.

  14. Fusion fuel cycle: material requirements and potential effluents

    SciTech Connect

    Teofilo, V.L.; Bickford, W.E.; Long, L.W.; Price, B.A.; Mellinger, P.J.; Willingham, C.E.; Young, J.K.

    1980-10-01

    Environmental effluents that may be associated with the fusion fuel cycle are identified. Existing standards for controlling their release are summarized and anticipated regulatory changes are identified. The ability of existing and planned environmental control technology to limit effluent releases to acceptable levels is evaluated. Reference tokamak fusion system concepts are described and the principal materials required of the associated fuel cycle are analyzed. These materials include the fusion fuels deuterium and tritium; helium, which is used as a coolant for both the blanket and superconducting magnets; lithium and beryllium used in the blanket; and niobium used in the magnets. The chemical and physical processes used to prepare these materials are also described.

  15. Aerogel Materials by Evaporative Drying: Potential for Space Applications

    NASA Technical Reports Server (NTRS)

    Plawsky, Joel L.

    1999-01-01

    Aerogel wafers were made using an evaporative drying procedure. The main steps were sol formulation, gelation, aging, capping, and drying. Of these, the most critical step was drying. Both the rate of evaporation and temperature of the system must be controlled for best results. Aerogel materials should be benchmarked against more traditional foams and current systems may have to be redesigned to make best use of aerogel strengths. Finally, the flexibility of this procedure lends itself to producing aerogel materials for many uses other than insulation. Such uses may include catalysis, sensing, and composite materials.

  16. Bioactivities and Health Benefits of Wild Fruits

    PubMed Central

    Li, Ya; Zhang, Jiao-Jiao; Xu, Dong-Ping; Zhou, Tong; Zhou, Yue; Li, Sha; Li, Hua-Bin

    2016-01-01

    Wild fruits are exotic or underutilized. Wild fruits contain many bioactive compounds, such as anthocyanins and flavonoids. Many studies have shown that wild fruits possess various bioactivities and health benefits, such as free radical scavenging, antioxidant, anti-inflammatory, antimicrobial, and anticancer activity. Therefore, wild fruits have the potential to be developed into functional foods or pharmaceuticals to prevent and treat several chronic diseases. In the present article, we review current knowledge about the bioactivities and health benefits of wild fruits, which is valuable for the exploitation and utilization of wild fruits. PMID:27527154

  17. Bioactivities and Health Benefits of Wild Fruits.

    PubMed

    Li, Ya; Zhang, Jiao-Jiao; Xu, Dong-Ping; Zhou, Tong; Zhou, Yue; Li, Sha; Li, Hua-Bin

    2016-08-04

    Wild fruits are exotic or underutilized. Wild fruits contain many bioactive compounds, such as anthocyanins and flavonoids. Many studies have shown that wild fruits possess various bioactivities and health benefits, such as free radical scavenging, antioxidant, anti-inflammatory, antimicrobial, and anticancer activity. Therefore, wild fruits have the potential to be developed into functional foods or pharmaceuticals to prevent and treat several chronic diseases. In the present article, we review current knowledge about the bioactivities and health benefits of wild fruits, which is valuable for the exploitation and utilization of wild fruits.

  18. Bioactivation of particles

    DOEpatents

    Pinaud, Fabien; King, David; Weiss, Shimon

    2011-08-16

    Particles are bioactivated by attaching bioactivation peptides to the particle surface. The bioactivation peptides are peptide-based compounds that impart one or more biologically important functions to the particles. Each bioactivation peptide includes a molecular or surface recognition part that binds with the surface of the particle and one or more functional parts. The surface recognition part includes an amino-end and a carboxy-end and is composed of one or more hydrophobic spacers and one or more binding clusters. The functional part(s) is attached to the surface recognition part at the amino-end and/or said carboxy-end.

  19. Seed Pro-Nutra Care: A tool for characterization of seed storage proteins and database of bioactive peptides having potential health benefits.

    PubMed

    Kumar, Anil; Goyal, Ajay; Goel, Anshita; Pandey, Dinesh

    2014-01-01

    Seed storage proteins, the major food proteins, possess unique physicochemical characteristics which determine their nutritional importance and influence their utilization by humans. Here, we describe a database driven tool named Seed Pro-Nutra Care which comprises a systematic compendium of seed storage proteins and their bioactive peptides influencing several vital organ systems for maintenance of health. Seed Pro-Nutra Careis an integrated resource on seed storage protein. This resource help in the (I) Characterization of proteins whether they belong to seed storage protein group or not. (II) Identification the bioactive peptides with their sequences using peptide name (III) Determination of physico chemical properties of seed storage proteins. (IV) Epitope identification and mapping (V) Allergenicity prediction and characterization. Seed Pro-Nutra Care is a compilation of data on bioactive peptides present in seed storage proteins from our own collections and other published and unpublished sources. The database provides an information resource of a variety of seed related biological information and its use for nutritional and biomedical application. http://www.gbpuat-cbsh.ac.in/departments/bi/database/seed_pro_nutra_care/

  20. Noise Abatement and Internal Vibrational Absorption in Potential Structural Materials

    DTIC Science & Technology

    1976-09-01

    Factor-Temperature Curves for Nitinol , Incramute I and Cobalt- Iron Alloys measured at a stress of 2000 psi in the Frequence Range from 150 to 250 Hertz...tion of these materials in specific military systems. Novel damping materials such as Nitinol (Ni-Ti) and copper-aluminum-nickel alloys which appear to...condition supplied by commercial vendors. The results for Nitinol displayed in Figure 1 have been optimized (2) by applying a 15% reduction in thickness

  1. Noise Abatement and Internal Vibrational Absorption in Potential Structural Materials

    DTIC Science & Technology

    1976-11-01

    Comparison of the Loss Factor-Temperature Curves for Nitinol , Incramute I and Cobalt- Iron Alloys measured at a...materials in specific military systems. Novel damping materials such as Nitinol (Ni-Ti) and copper-aluminum-nickel alloys which appear to derive their...Incramute are in the condition supplied by commercial vendors. The results for Nitinol displayed in Figure 1 have been optimized (2) through - a 15

  2. Bioactive-glass in periodontal surgery and implant dentistry.

    PubMed

    Profeta, Andrea Corrado; Prucher, Gian Marco

    2015-01-01

    Bioactive-glass (B-G) is a material known for its favorable biological response when in contact with surrounding fibro-osseous tissues, due not only to an osteoconductive property, but also to an osteostimulatory capacity, and superior biocompatibility for use in human body. The objectives of this paper are to review recent studies on B-G in periodontal and implant therapy, describing its basic properties and mechanism of activity as well as discoursing about state of art and future perspective of utilization. From a demonstrated clinical benefit as bone graft for the elimination of osseous defects due to periodontal disease (intrabony/furcation defects) and surgeries (alveolar ridge preservation, maxillary sinus augmentation), to a potential use for manufacturing bioactive dental implants, possibly allowing wider case selection criteria together with improved integration rates even in the more challenging osteoporotic and medically compromised patients, this biomaterial represents an important field of study with high academic, clinical and industrial importance.

  3. Beta-conglycinins among sources of bioactives in soybean hydrolysates that inhibited leukemia cells in vitro

    USDA-ARS?s Scientific Manuscript database

    Soybean is a complex matrix containing several potentially bioactive components. The objective was to build a statistical model to predict the anticancer potential of soybean based on the composition of bioactive components in soybean hydrolysates produced by simulated gastrointestinal digestion. ...

  4. Planctomycetes as Novel Source of Bioactive Molecules

    PubMed Central

    Graça, Ana P.; Calisto, Rita; Lage, Olga M.

    2016-01-01

    Marine environments are a fruitful source of bioactive compounds some of which are the newest leading drugs in medicinal therapeutics. Of particular importance are organisms like sponges and macroalgae and their associated microbiome. Planctomycetes, abundant in macroalgae biofilms, are promising producers of bioactive compounds since they share characteristics, like large genomes and complex life cycles, with the most bioactive bacteria, the Actinobacteria. Furthermore, genome mining revealed the presence of secondary metabolite pathway genes or clusters in 13 analyzed Planctomycetes genomes. In order to assess the antimicrobial production of a large and diverse collection of Planctomycetes isolated from macroalgae from the Portuguese coast, molecular, and bioactivity assays were performed in 40 bacteria from several taxa. Two genes commonly associated with the production of bioactive compounds, nonribosomal peptide synthetases (NRPS), and polyketide synthases (PKS) genes were screened. Molecular analysis revealed that 95% of the planctomycetes potentially have one or both secondary bioactive genes; 85% amplified with PKS-I primers and 55% with NRPS primers. Some of the amplified genes were confirmed to be involved in secondary metabolite pathways. Using bioinformatic tools their biosynthetic pathways were predicted. The secondary metabolite genomic potential of strains LF1, UC8, and FC18 was assessed using in silico analysis of their genomes. Aqueous and organic extracts of the Planctomycetes were evaluated for their antimicrobial activity against an environmental Escherichia coli, E. coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633, and a clinical isolate of Candida albicans. The screening assays showed a high number of planctomycetes with bioactive extracts revealing antifungal (43%) and antibacterial (54%) activity against C. albicans and B. subtilis, respectively. Bioactivity was observed in

  5. Planctomycetes as Novel Source of Bioactive Molecules.

    PubMed

    Graça, Ana P; Calisto, Rita; Lage, Olga M

    2016-01-01

    Marine environments are a fruitful source of bioactive compounds some of which are the newest leading drugs in medicinal therapeutics. Of particular importance are organisms like sponges and macroalgae and their associated microbiome. Planctomycetes, abundant in macroalgae biofilms, are promising producers of bioactive compounds since they share characteristics, like large genomes and complex life cycles, with the most bioactive bacteria, the Actinobacteria. Furthermore, genome mining revealed the presence of secondary metabolite pathway genes or clusters in 13 analyzed Planctomycetes genomes. In order to assess the antimicrobial production of a large and diverse collection of Planctomycetes isolated from macroalgae from the Portuguese coast, molecular, and bioactivity assays were performed in 40 bacteria from several taxa. Two genes commonly associated with the production of bioactive compounds, nonribosomal peptide synthetases (NRPS), and polyketide synthases (PKS) genes were screened. Molecular analysis revealed that 95% of the planctomycetes potentially have one or both secondary bioactive genes; 85% amplified with PKS-I primers and 55% with NRPS primers. Some of the amplified genes were confirmed to be involved in secondary metabolite pathways. Using bioinformatic tools their biosynthetic pathways were predicted. The secondary metabolite genomic potential of strains LF1, UC8, and FC18 was assessed using in silico analysis of their genomes. Aqueous and organic extracts of the Planctomycetes were evaluated for their antimicrobial activity against an environmental Escherichia coli, E. coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633, and a clinical isolate of Candida albicans. The screening assays showed a high number of planctomycetes with bioactive extracts revealing antifungal (43%) and antibacterial (54%) activity against C. albicans and B. subtilis, respectively. Bioactivity was observed in

  6. The Kendall College Human Potential Seminar: Guidelines and Materials.

    ERIC Educational Resources Information Center

    Kleemann, Joseph L.

    The aim of the Kendall College Human Potential Seminar (KCHPS) is to provide a structure within which persons can generate and share extensive positive information about themselves. It also creates greater participant awareness of, and respect for, human potential--their own as well as that of others. This paper consists of guidelines and…

  7. Lightweight Intermetallics with Laves Structures as Potential Hydrogen Storage Materials

    NASA Astrophysics Data System (ADS)

    Billet, Beau Austin

    Hydrogen storage was identified by the US Department of Energy as a "grand challenge" for the implementation of hydrogen-powered fuel cell vehicles for reduced CO2 emissions from transportation vehicles. None of the hydrogen storage options currently developed can satisfy the high gravimetric, volumetric and system design requirements. Intermetallic compounds with Laves structures in the formula of AB2 have long been known to store hydrogen in their interstitial sites to serve as reversible hydrogen storage materials (A and B are metallic elements). They have the potential to be hydrided to a maximum of ~ AB2H6 due to the impeding H-H interactions at neighboring interstitial sites. To achieve the highest weight percent of hydrogen storage in AB2H6, the lowest combined atomic weight of AB2 is required. The CaLi2 compound is the lightest known Laves phase, but it could not maintain its Laves structure when it was hydrided. Existing work of Akiba's group showed that a ternary Laves phase CaLi1.8Mg0.2 could be hydrided to form a hydrogenated Laves phase, but the absorbed hydrogen could not be released for reversible storage. Substitutions (Ca,X)Li1.8Mg0.2 are explored in the present study to see whether heavier elements [X = Sr, Ba and Ce] in small quantities can make the lightweight Laves compounds reversibly store hydrogen. Induction melting was successful in obtaining the desired Laves phases. The base system, CaLi1.8Mg0.2, formed a single phase, consistent with the literature result. Both Ca0.9Ba0.1Li 1.8Mg0.2 and Ca0.9Ce0.1Li1.8Mg 0.2 also formed a single-phase C14 Laves, whereas both Ca0.9Sr 0.1Li1.8Mg0.2 and Ca0.8Sr0.2Li 1.8Mg0.2 formed two seperature Laves phases with the same crystal structure, indicating a phase separation. The Ca0.8Ba 0.2Li1.8Mg0.2 composition completely lost the Laves-phase structure, forming CaLi2, CaMg2, BaLi 4 and Ca. All compounds tested at temperatures from 25 °C to 150 °C show the characteristic "plateau" behavior in the pressure

  8. Synthetic polymers and their potential as genetic materials.

    PubMed

    Pinheiro, Vitor B; Loakes, David; Holliger, Philipp

    2013-02-01

    DNA and RNA are the only known natural genetic materials. Systematic modification of each of their chemical building blocks (nucleobase, sugar, and phosphate) has enabled the study of the key properties that make those nucleic acids genetic materials. All three moieties contribute to replication and, significantly, all three moieties can be replaced by synthetic analogs without loss of function. Synthetic nucleic acid polymers capable of storing and propagating information not only expand the central dogma, but also highlight that DNA and RNA are not unique chemical solutions for genetic information storage. By considering replication as a question of information transfer, we propose that any polymer that can be replicated could serve as a genetic material. Copyright © 2013 WILEY Periodicals, Inc.

  9. Chelating Tendencies of Bioactive Aminophosphonates

    PubMed Central

    Lázár, István; Kafarski, Pawel

    1994-01-01

    The metal-binding abilities of a wide variety of bioactive aminophosphonates, from the simple aminoethanephosphonic acids to the rather large macrocyclic polyaza derivatives, are discussed with special emphasis on a comparison of the analogous carboxylic acid and phosphonic acid systems. Examples are given of the biological importance of metal ion – aminophosphonate interactions in living systems, and also of their actual and potential applicability in medicine. PMID:18476237

  10. Engineered Plants Make Potential Precursor to Raw Material for Plastics

    SciTech Connect

    Shanklin, John

    2010-11-02

    In a first step toward achieving industrial-scale green production, scientists from BNL and collaborators at Dow AgroSciences report engineering a plant that produces industrially relevant levels of chemicals that could potentially be used to make plastics.

  11. Engineered Plants Make Potential Precursor to Raw Material for Plastics

    ScienceCinema

    Shanklin, John

    2016-10-19

    In a first step toward achieving industrial-scale green production, scientists from BNL and collaborators at Dow AgroSciences report engineering a plant that produces industrially relevant levels of chemicals that could potentially be used to make plastics.

  12. Potential contribution of low cost materials in clean technology

    NASA Astrophysics Data System (ADS)

    Smail, Heman A.; Shareef, Kafia M.; Ramli, Zainab

    2016-03-01

    As the world's population approaches more than 9 billion, the strain on the planet's resources is steadily increasing. This demand can only be met by improving production methods to reduce the use of chemicals and the amount of chemical waste. Zeolites are among the least-known products for environmental pollution control, separation science and technology. This study investigates whether the use of geological sources as low-cost materials are suitable for zeolite synthesis and future applications. In this investigation natural montmorillonite clay, locally available in Erbil-Kurdistan, was used as raw material. The experiments were carried out in the presence of ultrasound 30KHz at 60°C and for different crystallization times (5, 10 &15 hours) and the results were compared with those obtained by performing conventional alkaline hydrothermal static syntheses under similar conditions and crystallization time of (90 hours). The raw material as well as the products was analyzed using; Fourier Transform Infra-Red (FT-IR), X-Ray Diffraction (XRD) and X-Ray Fluorescence (XRF) spectroscopy and scanning electron microscope (SEM). The experimental data were ascertained the formation of Zeolite successfully. Crystallization by ultrasound has been demonstrated to offer the possibilities of increasing the nucleation and crystallization rates of zeolites, improving the yield and directing the synthesis towards different crystal phases.

  13. Studying Soft Materials with Soft Potentials -- Fast Monte Carlo Simulations

    NASA Astrophysics Data System (ADS)

    Zong, Jing; Zhang, Xinghua; Zhang, Pengfei; Yin, Yuhua; Li, Baohui; Wang, Qiang

    2010-03-01

    The basic idea of fast Monte Carlo (FMC) simulationsfootnotetextQ. Wang and Y. Yin, J. Chem. Phys., 130, 104903 (2009); Q. Wang, Soft Matter, 5, 4564 (2009). is to use soft potentials that allow particle overlapping, instead of hard repulsions (e.g., the Lennard-Jones potential in continuum or the self- and mutual-avoiding walks on a lattice) used in conventional molecular simulations. This gives orders of magnitude faster/better sampling of configurational space. In addition, since soft potentials are commonly used in polymer field theories, using the same Hamiltonian in both FMC simulations and the theories thus allow stringent test of the latter, without any parameter-fitting, to unambiguously and quantitatively reveal the consequences of theoretical approximations. Here we use several systems, ranging from small-molecule liquid crystals to homopolymer solutions and brushes, to demonstrate these great advantages of FMC simulations performed both in continuum and on a lattice.

  14. Metallic bionanocatalysts: potential applications as green catalysts and energy materials.

    PubMed

    Macaskie, Lynne E; Mikheenko, Iryna P; Omajai, Jacob B; Stephen, Alan J; Wood, Joseph

    2017-08-22

    Microbially generated or supported nanocatalysts have potential applications in green chemistry and environmental application. However, precious (and base) metals biorefined from wastes may be useful for making cheap, low-grade catalysts for clean energy production. The concept of bionanomaterials for energy applications is reviewed with respect to potential fuel cell applications, bio-catalytic upgrading of oils and manufacturing 'drop-in fuel' precursors. Cheap, effective biomaterials would facilitate progress towards dual development goals of sustainable consumption and production patterns and help to ensure access to affordable, reliable, sustainable and modern energy. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  15. Fiber glass-bioactive glass composite for bone replacing and bone anchoring implants.

    PubMed

    Vallittu, Pekka K; Närhi, Timo O; Hupa, Leena

    2015-04-01

    Although metal implants have successfully been used for decades, devices made out of metals do not meet all clinical requirements, for example, metal objects may interfere with some new medical imaging systems, while their stiffness also differs from natural bone and may cause stress-shielding and over-loading of bone. Peer-review articles and other scientific literature were reviewed for providing up-dated information how fiber-reinforced composites and bioactive glass can be utilized in implantology. There has been a lot of development in the field of composite material research, which has focused to a large extent on biodegradable composites. However, it has become evident that biostable composites may also have several clinical benefits. Fiber reinforced composites containing bioactive glasses are relatively new types of biomaterials in the field of implantology. Biostable glass fibers are responsible for the load-bearing capacity of the implant, while the dissolution of the bioactive glass particles supports bone bonding and provides antimicrobial properties for the implant. These kinds of combination materials have been used clinically in cranioplasty implants and they have been investigated also as oral and orthopedic implants. The present knowledge suggests that by combining glass fiber-reinforced composite with particles of bioactive glass can be used in cranial implants and that the combination of materials may have potential use also as other types of bone replacing and repairing implants. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  16. Conductive porous scaffolds as potential neural interface materials.

    SciTech Connect

    Hedberg-Dirk, Elizabeth L.; Cicotte, Kirsten N.; Buerger, Stephen P.; Reece, Gregory; Dirk, Shawn M.; Lin, Patrick P.

    2011-11-01

    Our overall intent is to develop improved prosthetic devices with the use of nerve interfaces through which transected nerves may grow, such that small groups of nerve fibers come into close contact with electrode sites, each of which is connected to electronics external to the interface. These interfaces must be physically structured to allow nerve fibers to grow through them, either by being porous or by including specific channels for the axons. They must be mechanically compatible with nerves such that they promote growth and do not harm the nervous system, and biocompatible to promote nerve fiber growth and to allow close integration with biological tissue. They must exhibit selective and structured conductivity to allow the connection of electrode sites with external circuitry, and electrical properties must be tuned to enable the transmission of neural signals. Finally, the interfaces must be capable of being physically connected to external circuitry, e.g. through attached wires. We have utilized electrospinning as a tool to create conductive, porous networks of non-woven biocompatible fibers in order to meet the materials requirements for the neural interface. The biocompatible fibers were based on the known biocompatible material poly(dimethyl siloxane) (PDMS) as well as a newer biomaterial developed in our laboratories, poly(butylene fumarate) (PBF). Both of the polymers cannot be electrospun using conventional electrospinning techniques due to their low glass transition temperatures, so in situ crosslinking methodologies were developed to facilitate micro- and nano-fiber formation during electrospinning. The conductivity of the electrospun fiber mats was controlled by controlling the loading with multi-walled carbon nanotubes (MWNTs). Fabrication, electrical and materials characterization will be discussed along with initial in vivo experimental results.

  17. Chitosan membranes containing micro or nano-size bioactive glass particles: evolution of biomineralization followed by in situ dynamic mechanical analysis.

    PubMed

    Caridade, Sofia G; Merino, Esther G; Alves, Natália M; Bermudez, Verónica de Zea; Boccaccini, Aldo R; Mano, João F

    2013-04-01

    A new family of biodegradable polymer/bioactive glass (BG) composite materials has emerged based on the availability of nano-sized bioactive particles. Such novel biocomposites can have enhanced performance, in terms of mechanical properties and bioactivity, and they can be designed to be used in bone regeneration approaches. In this work, membranes of chitosan (CTS) and chitosan with bioactive glass (BG) both micron and nano sized particles (CTS/μBG, CTS/nBG, respectively) were prepared by solvent casting. Microstructural and mechanical properties were evaluated in order to compare the effects of the incorporation of micro (μBG) and nano (nBG) particles in the chitosan matrix. In vitro bioactivity tests were performed to characterize the apatite layer that is formed on the surface of the material after being immersed in simulated body fluid (SBF). The biomineralization process on the biomaterials was also followed using non-conventional dynamic mechanical analysis (DMA), both online and offline. In such DMA experiments, the change in the storage modulus, E', and the loss factor, tan δ, were measured as a function of the immersion time in SBF. The results demonstrated that CTS/nBG membranes possess enhanced mechanical properties and higher bioactivity in comparison with the CTS/μBG membranes. Such results suggest the potential of nBG for the development of bioactive composites for bone regeneration applications.

  18. Marine Peptides: Bioactivities and Applications

    PubMed Central

    Cheung, Randy Chi Fai; Ng, Tzi Bun; Wong, Jack Ho

    2015-01-01

    Peptides are important bioactive natural products which are present in many marine species. These marine peptides have high potential nutraceutical and medicinal values because of their broad spectra of bioactivities. Their antimicrobial, antiviral, antitumor, antioxidative, cardioprotective (antihypertensive, antiatherosclerotic and anticoagulant), immunomodulatory, analgesic, anxiolytic anti-diabetic, appetite suppressing and neuroprotective activities have attracted the attention of the pharmaceutical industry, which attempts to design them for use in the treatment or prevention of various diseases. Some marine peptides or their derivatives have high commercial values and had reached the pharmaceutical and nutraceutical markets. A large number of them are already in different phases of the clinical and preclinical pipeline. This review highlights the recent research in marine peptides and the trends and prospects for the future, with special emphasis on nutraceutical and pharmaceutical development into marketed products. PMID:26132844

  19. Marine Peptides: Bioactivities and Applications.

    PubMed

    Cheung, Randy Chi Fai; Ng, Tzi Bun; Wong, Jack Ho

    2015-06-29

    Peptides are important bioactive natural products which are present in many marine species. These marine peptides have high potential nutraceutical and medicinal values because of their broad spectra of bioactivities. Their antimicrobial, antiviral, antitumor, antioxidative, cardioprotective (antihypertensive, antiatherosclerotic and anticoagulant), immunomodulatory, analgesic, anxiolytic anti-diabetic, appetite suppressing and neuroprotective activities have attracted the attention of the pharmaceutical industry, which attempts to design them for use in the treatment or prevention of various diseases. Some marine peptides or their derivatives have high commercial values and had reached the pharmaceutical and nutraceutical markets. A large number of them are already in different phases of the clinical and preclinical pipeline. This review highlights the recent research in marine peptides and the trends and prospects for the future, with special emphasis on nutraceutical and pharmaceutical development into marketed products.

  20. Effect of material, process parameters, and simulated body fluids on mechanical properties of 13-93 bioactive glass porous constructs made by selective laser sintering.

    PubMed

    Kolan, Krishna C R; Leu, Ming C; Hilmas, Gregory E; Velez, Mariano

    2012-09-01

    The effect of particle size distribution, binder content, processing parameters, and sintering schedule on the microstructure and mechanical properties of porous constructs was investigated. The porous constructs were produced by indirect selective laser sintering (SLS) of 13-93 bioactive glass using stearic acid as a polymeric binder. The binder content and d(50) particle size in the feedstock powders were simultaneously reduced from 22 to 12 wt% and from 20 to 11 μm, respectively, to identify the minimum binder content required for the SLS fabrication. An average particle size of ∼16 μm with a binder content of 15 wt% significantly reduced post-processing time and improved mechanical properties. Increasing the laser power and scan speed at the energy density of 1 cal/cm² maintained the feature sharpness of the parts during the fabrication of green parts and could almost double the mechanical properties of the sintered parts. Changes in the heating rates, ranging from 0.1 to 2 °C/min, during the post-processing of the fabricated "green" scaffolds showed that the heating rate significantly affects the densification and mechanical properties of the sintered scaffolds. The compressive strength of the scaffolds manufactured with the optimized parameters varied from 41 MPa, for a scaffold with a porosity of ∼50%, to 157 MPa, for a dense part. The bioactive scaffolds soaked in simulated body fluids for durations up to 6 weeks were used to evaluate the change in mechanical properties in vitro.

  1. Four-point potential drop measurements for materials characterization

    NASA Astrophysics Data System (ADS)

    Bowler, Nicola

    2011-01-01

    The technique of measuring the voltage difference (potential drop) between two of the four electrodes of a four-point probe, in order to determine conductivity or surface resistivity of a test piece, is well established in the direct-current (dc) or quasi-dc regime. The technique finds wide usage in the semiconductor industry for the purpose of measuring surface resistivity of semiconductors, and also in the measurement of conductivity of metals, particularly of ferromagnetic metals for which conductivity cannot be easily measured using eddy-current nondestructive evaluation (NDE). In these applications, the conductivity of the test piece is deduced from an analytic formula that depends on the geometry of the probe and test piece. Such a formula requires, as an input, the measured value of the potential drop. Several analytical expressions exist for a variety of test-piece geometries and probe arrangements. Recently, it has been shown that broadband measurements of the potential drop, known as 'alternating current potential drop' (ac PD) measurements, can be used not only to obtain the conductivity of a test piece, but also its linear permeability μ. The beauty of this measurement is that the two parameters are completely decoupled in the quasi-static regime. In fact, μ does not appear in the quasi-static expression for σ. Hence, σ may be obtained from low-frequency ac PD measurements and then μ may be deduced as the frequency increases beyond the quasi-static regime, once σ is known. In this review, both dc and ac solutions that are useful in determining the conductivity of metals and semiconductors, and the permeability of ferromagnetic conductors, are summarized. In particular, flat test pieces with arbitrary thickness are considered. At the next level of complexity, a solution for a half-space coated with a surface layer is given, along with a discussion of the use of the four-point potential drop method for determining thickness of a surface layer, such

  2. Preparation and In Vitro Biological Evaluation of Octacalcium Phosphate/Bioactive Glass-Chitosan/ Alginate Composite Membranes Potential for Bone Guided Regeneration.

    PubMed

    Xu, Sanzhong; Chen, Xiaoyi; Yang, Xianyan; Zhang, Lei; Yang, Guojing; Shao, Huifeng; He, Yong; Gou, Zhongru

    2016-06-01

    The chitosan/alginate-trace element-codoped octacalcium phosphate/nano-sized bioactive glass (CS/ALG-teOCP/nBG) composite membranes were prepared by a layer-by-layer coating method for the functional requirement of guided bone regeneration (GBR). The morphology, mechanical properties and moisture content of the membranes was studied by scanning electron microscopy (SEM) observation, mechanical and swelling test. The results showed that the teOCP/nBG distributed uniformly in the composite membranes, and such as-prepared composite membrane exhibited an excellent tensile strength, accompanying with mechanical decay with immersion in aqueous medium. Cell culture and MTT assays showed that the surface microstructure and the ion dissolution products from teOCP/nBG components could enhance the cell proliferation, and especially the composite membranes was suitable for supporting the adhesion and growth behavior of human bone marrow mesenchymal stem cells (hBMSCs) in comparison with the CS/ALG pure polymer membranes. These results suggest that the new CS/ALG-teOCP/nBG composite membrane is highly bioactive and biodegradable, and favorable for guiding bone regeneration.

  3. Evaluation of Rumex hastatus D. Don for cytotoxic potential against HeLa and NIH/3T3 cell lines: chemical characterization of chloroform fraction and identification of bioactive compounds.

    PubMed

    Ahmad, Sajjad; Ullah, Farhat; Zeb, Anwar; Ayaz, Muhammad; Ullah, Farman; Sadiq, Abdul

    2016-08-24

    The importance of Rumex genus and the renowned ethnopharmacological and biological potentials of Rumex hastatus is evident from the previous reports. Recently the R. hastatus has been evaluated for anticancer potential against HepG2, MCF7 or LNCaP cell lines with considerable cytotoxicity. We also reported the anti-tumor and anti-angiogenic potentials of R. hastatus. The current study has been arranged to evaluate cytotoxic potential of this plant against HeLa and NIH/3T3 cell lines and sort out the most active fraction of R. hastatus along with the identification of bioactive compounds responsible for cytotoxicity. The cytotoxic potential of methanolic extract and sub-fractions of R. hastatus was performed following (3-[4, 5-dimethylthiazole-2-yl]-2, 5-diphenyl-tetrazolium bromide) MTT calorimetric assay. Four concentrations (500, 250, 125 and 62.5 μg/ml) of each sample were used against both cell lines. Two cell lines i.e. HeLa and NIH/3T3 were used in the assay. Furthermore, chemical characterization of chloroform fraction was performed by GC-MS analysis. The current investigational study demonstrates that all the solvent fractions of R. hastatus were active against HeLa and NIH/3T3 cell lines. Among all the fractions, chloroform fraction was dominant in activity against both cell lines. The observed IC50 values of chloroform fraction were 151.52 and 53.37 μg/ml against HeLa and NIH/3T3 respectively. The GC-MS analysis of chloroform fraction revealed the identification of 78 compounds with the identification of bioactive ones like ar-tumerone, phytol, dihydrojasmone, sitostenone etc. It can be concluded from our results that Rumex hastatus D. Don possess strong cytotoxic potential. Moreover, the observed IC50 values and GC-MS analysis of chloroform fraction reveal that most of the bioactive compounds are in chloroform fraction. It can be further deduce that the chloroform fraction is a suitable target for the isolation of compounds having potential role in

  4. Dental adhesives with bioactive and on-demand bactericidal properties.

    PubMed

    Welch, Ken; Cai, Yanling; Engqvist, Håkan; Strømme, Maria

    2010-05-01

    The aim of the present work was to perform the first in vitro evaluation of a new interfacial bond-promoting material-and-method concept for on-demand long term bacteria inhibition in dental restoration procedures. The bioactivity, mechanical bonding strength and photocatalytic bactericidal properties, induced by low dose ultraviolet-A (UV-A) irradiation of dental adhesives containing crystalline titania nanoparticles (NPs), were analyzed. Dental adhesives with a NP content of 20wt% were shown to be bioactive in terms of spontaneous hydroxylapatite formation upon storage in simulated body fluid and the bioactivity was found to be promoted by chemical etching of the adhesives. The mechanical bonding strength between the adhesives and a HA tooth model was shown to be unaffected by the NPs up to a NP content of 30wt%. Elimination of Staphylococcus epidermidis in contact with the adhesives was found to depend both on UV photocatalytic irradiation intensity and time. Efficient elimination of the bacteria could be achieved using a UV-A dose of 4.5J/cm(2) which is about 6 times below the safe maximum UV dose according to industry guidelines, and 20 times below the average UV-A dose received during an ordinary sun bed session. The combined features of bioactivity and on-demand bactericidal effect should open up the potential to create dental adhesives that reduce the incidence of secondary caries and promote closure of gaps forming at the interface towards the tooth via remineralization of adjacent tooth substance, as well as prevention of bacterial infections via on-demand UV-A irradiation. 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  5. Laser photopolymerization of dental materials with potential endodontic applications.

    PubMed

    Potts, T V; Petrou, A

    1990-06-01

    Photopolymerizing resins were exposed to three different wavelengths of light emanating from the argon laser. It was determined that the most efficient wavelengths for photopolymerization of camphorquinone-activated resins were at 477 and 488 nm. The 514.5-nm wavelength was relatively ineffective in activating polymerization. Four camphorquinone-activated resins were placed in the root canals of teeth and tested for polymerization depth using a 488-nm wavelength laser beam coupled to an optical fiber 200 microns in diameter. In regard to polymerization depth, these materials ranked as follows: Genesis greater than Prisma-Fil greater than Prisma Microfine greater than Prisma VLC Dycal. Alterations in the positions of the optical fiber and the surface of the resin in the canal made only minor differences in polymerization depth of the samples. The results indicate that an argon laser coupled to an optical fiber could become a useful modality in endodontic therapy.

  6. Advances on Bioactive Polysaccharides from Medicinal Plants.

    PubMed

    Xie, Jian-Hua; Jin, Ming-Liang; Morris, Gordon A; Zha, Xue-Qiang; Chen, Han-Qing; Yi, Yang; Li, Jing-En; Wang, Zhi-Jun; Gao, Jie; Nie, Shao-Ping; Shang, Peng; Xie, Ming-Yong

    2016-07-29

    In recent decades, the polysaccharides from the medicinal plants have attracted a lot of attention due to their significant bioactivities, such as anti-tumor activity, antioxidant activity, anticoagulant activity, antidiabetic activity, radioprotection effect, anti-viral activity, hypolipidemic and immunomodulatory activities, which make them suitable for medicinal applications. Previous studies have also shown that medicinal plant polysaccharides are non-toxic and show no side effects. Based on these encouraging observations, most researches have been focusing on the isolation and identification of polysaccharides, as well as their bioactivities. A large number of bioactive polysaccharides with different structural features and biological effects from medicinal plants have been purified and characterized. This review provides a comprehensive summary of the most recent developments in physiochemical, structural features and biological activities of bioactive polysaccharides from a number of important medicinal plants, such as polysaccharides from Astragalus membranaceus, Dendrobium plants, Bupleurum, Cactus fruits, Acanthopanax senticosus, Angelica sinensis (Oliv.) Diels, Aloe barbadensis Miller, and Dimocarpus longan Lour. Moreover, the paper has also been focused on the applications of bioactive polysaccharides for medicinal applications. Recent studies have provided evidence that polysaccharides from medicinal plants can play a vital role in bioactivities. The contents and data will serve as a useful reference material for further investigation, production, and application of these polysaccharides in functional foods and therapeutic agents.

  7. Organic hydrogels as potential sorbent materials for water purification

    NASA Astrophysics Data System (ADS)

    Linardatos, George; Bekiari, Vlasoula; Bokias, George

    2014-05-01

    Hydrogels are three-dimensional, hydrophilic, polymeric networks capable to adsorb large amounts of water or biological fluids. The networks are composed of homopolymers or copolymers and are insoluble due to the presence of chemical or physical cross-links. Depending on the nature of the structural units, swelling or shrinking of these gels can be activated by several external stimuli, such as solvent, heat, pH, electric stimuli. As a consequence, these materials are attractive for several applications in a variety of fields: drug delivery, muscle mimetic soft linear actuators, hosts of nanoparticles and semiconductors, regenerative medicine etc. Of special interest is the application of hydrogels for water purification, since they can effectively adsorb several water soluble pollutants such as metal ions, inorganic or organic anions, organic dyestaff, etc. In the present work, anionic hydrogels bearing negatively charged -COO- groups were prepared and investigated. These are based on the anionic monomer sodium acrylate (ANa) and the nonionic one N,N-dimethylacrylamide (DMAM). A series of copolymeric hydrogels (P(DMAM-co-ANax) were synthesized. The molar content x of ANa units (expressing the molar charged content of the hydrogel) varies from 0 (nonionic poly(N,N-dimethylacrylamide), PDMAM, hydrogel) up to 1 (fully charged poly(sodium acrylate), PANa, hydrogel). The hydrogels were used to extract organic or inorganic solutes from water. Cationic and anionic model dyes, as well as multivalent inorganic ions, have been studied. It is found that cationic dyes are strongly adsorbed and retained by the hydrogels,