Search results for: hollow fiber membrane
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2458

Search results for: hollow fiber membrane

328 The Changes of Chemical Composition of Rice Straw Treated by a Biodecomposer Developed from Rumen Bacterial of Buffalo

Authors: A. Natsir, M. Nadir, S. Syahrir, A. Mujnisa

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In tropical countries such as in Indonesia, rice straw plays an important role in fulfilling the needs of feed for ruminant, especially during the dry season in which the availability of forage is very limited. However, the main problem of using rice straw as a feedstuff is low digestibility due to the existence of the links between lignin and cellulose or hemicellulose, and imbalance of its minerals content. One alternative to solve this problem is by application of biodecomposer (BS) derived from rumen bacterial of the ruminant. This study was designed to assess the effects of BS application on the changes of the chemical composition of rice straw. Four adults local buffalo raised under typical feeding conditions were used as a source of inoculum for BS development. The animal was fed for a month with a diet consisted of rice straw and elephant grass before taking rumen fluid samples. Samples of rumen fluid were inoculated in the carboxymethyl cellulose (CMC) media under anaerobic condition for 48 hours at 37°C. The mixture of CMC media and microbes are ready to be used as a biodecomposer following incubation of the mixture under anaerobic condition for 7 days at 45°C. The effectiveness of BS then assessed by applying the BS on the straw according to completely randomized design consisted of four treatments and three replication. One hundred g of ground coarse rice straw was used as the substrate. The BS was applied to the rice straw substrate with the following composition: Rice straw without BS (P0), rice straw + 5% BS (P1), rice straw +10% BS (P2), and rice straw + 15% BS. The mixture of rice straw and BS then fermented under anaerobic for four weeks. Following the fermentation, the chemical composition of rice straw was evaluated. The results indicated that the crude protein content of rice straw significantly increased (P < 0.05) as the level of BS increased. On the other hand, the concentration of crude fiber of the rice straw was significantly decreased (P < 0.05) as the level of BS increased. Other nutrients such as minerals did not change (P > 0.05) due to the treatments. In conclusion, application of BS developed from rumen bacterial of buffalo has a promising prospect to be used as a biological agent to improve the quality of rice straw as feeding for ruminant.

Keywords: biodecomposer, local buffalo, rumen microbial, chemical composition

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327 Bioaccessible Phenolics, Phenolic Bioaccessibilities and Antioxidant Activities of Cookies Supplemented with Pumpkin Flour

Authors: Emine Aydin, Duygu Gocmen

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In this study, pumpkin flours (PFs) were used to replace wheat flour in cookie formulation at three different levels (10%, 20% and 30% w/w). For this purpose PFs produced by two different applications (with or without metabisulfite pre-treatment) and then dried in freeze dryer. Control sample included no PFs. The total phenolic contents of the cookies supplemented with PFs were higher than that of control and gradually increased in total phenolic contents of cookies with increasing PF supplementation levels. Phenolic content makes also significant contribution on nutritional excellence of the developed cookies. Pre-treatment with metabisulfite (MS) had a positive effect on free, bound and total phenolics of cookies which are supplemented with various levels of MS-PF. This is due to a protective effect of metabisulfite pretreatment for phenolic compounds in the pumpkin flour. Phenolic antioxidants may act and absorb in a different way in humans and thus their antioxidant and health effects will be changed accordingly. In the present study phenolics’ bioavailability of cookies was investigated in order to assess PF as sources of accessible phenolics. The content of bioaccessible phenolics and phenolic bioaccessibility of cookies supplemented with PFs had higher than those of control sample. Cookies enriched with 30% MS-PF had the highest bioaccessible phenolics (597.86 mg GAE 100g-1) and phenolic bioaccessibility (41.71%). MS application in PF production caused a significant increase in phenolic bioaccessibility of cookies. According to all assay (ABTS, CUPRAC, FRAP and DPPH), antioxidant activities of cookies with PFs higher than that of control cookie. It was also observed that the cookies supplemented with MS-PF had significantly higher antioxidant activities than those of cookies including PF. In presented study, antioxidative bioaccessibilities of cookies were also determined. The cookies with PFs had significantly (p ≤ 0.05) higher antioxidative bioaccessibilities than control ones. Increasing PFs levels enhanced antioxidative bioaccessibilities of cookies. As a result, PFs addition improved the nutritional and functional properties of cookie by causing increase in antioxidant activity, total phenolic content, bioaccessible phenolics and phenolic bioaccessibilities.

Keywords: phenolic compounds, antioxidant activity, dietary fiber, pumpkin, freeze drying, cookie

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326 Generation of Ultra-Broadband Supercontinuum Ultrashort Laser Pulses with High Energy

Authors: Walid Tawfik

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The interaction of intense short nano- and picosecond laser pulses with plasma leads to reach variety of important applications, including time-resolved laser induced breakdown spectroscopy (LIBS), soft x-ray lasers, and laser-driven accelerators. The progress in generating of femtosecond down to sub-10 fs optical pulses has opened a door for scientists with an essential tool in many ultrafast phenomena, such as femto-chemistry, high field physics, and high harmonic generation (HHG). The advent of high-energy laser pulses with durations of few optical cycles provided scientists with very high electric fields, and produce coherent intense UV to NIR radiation with high energy which allows for the investigation of ultrafast molecular dynamics with femtosecond resolution. In this work, we could experimentally achieve the generation of a two-octave-wide supercontinuum ultrafast pulses extending from ultraviolet at 3.5 eV to the near-infrared at 1.3 eV in neon-filled capillary fiber. These pulses are created due to nonlinear self-phase modulation (SPM) in neon as a nonlinear medium. The measurements of the generated pulses were performed using spectral phase interferometry for direct electric-field reconstruction. A full characterization of the output pulses was studied. The output pulse characterization includes the pulse width, the beam profile, and the spectral bandwidth. Under optimization conditions, the reconstructed pulse intensity autocorrelation function was exposed for the shorts possible pulse duration to achieve transform-limited pulses with energies up to 600µJ. Furthermore, the effect of variation of neon pressure on the pulse-width was studied. The nonlinear SPM found to be increased with the neon pressure. The obtained results may give an opportunity to monitor and control ultrafast transit interaction in femtosecond chemistry.

Keywords: femtosecond laser, ultrafast, supercontinuum, ultra-broadband

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325 Early Onset Neonatal Sepsis Pathogens in Malaysian Hospitals: Determining Empiric Antibiotic

Authors: Nazedah Ain Ibrahim, Mohamed Mansor Manan

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Treatment of suspected early onset neonatal sepsis (EONS) in Neonatal Intensive Care Unit (NICU) is essential. However, information regarding EONS pathogens may vary between regions. Global perspectives showed Group B Streptococcal (GBS) as the most common causative pathogens, but the widespread use of intrapartum antibiotics has changed the pathogens pattern towards gram negative microorganisms, especially E. coli. Objective of this study is to describe the pathogens isolated, to assess current treatment and risk of EONS. Records of 899 neonates born in three General Hospitals between 2009 until 2012 were retrospectively reviewed. The inclusion criteria were neonates with blood culture taken prior to empiric antibiotics administration and within 72 hours of life. Of the study group, a total of 734 (82%) cases had documented blood culture that met the inclusion criteria. Proven EONS (as confirmed by positive blood culture) was found in 22 (3%) neonates. The majority was isolated with gram positive organisms, 17 (2.3%). In addition, other common gram positive organism isolated were Coagulase negative staphylococci (7) followed by Bacillus sp. (5) and Streptococcus pneumonia (2), and only one case isolated with GBS, Streptococcus spp. and Enterococcus sp. Meanwhile, only five cases of gram negative organisms [Stenotropomonas (xantho) maltophi (1), Haemophilus influenza (1), Spingomonas paucimobilis (1), Enterobacter gergoviae (1) and E. coli (1)] were isolated. A total of 286 (39%) cases were exposed to intrapartum antibiotics and of those, 157 (21.4%) were administered prior to delivery. All grams positive and most gram negative organisms showed sensitivity to the tested antibiotics. Only two rare gram negative organisms showed total resistant. Male, surfactant, caesarean delivery and prolonged rapture of membrane >18hours were a possible risk of proven EONS. Although proven EONS remains uncommon in Malaysia, nonetheless, the effect of intrapartum antibiotics still required continuous surveillance. However, by analyzing isolated pathogens it can be used as treatment guidance in managing suspected EONS.

Keywords: early onset neonatal sepsis, neonates, pathogens, gram positive, gram negative

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324 Substituted Thiazole Analogues as Anti-Tumor Agents

Authors: Menna Ewida, Dalal Abou El-Ella, Dina Lasheen, Huessin El-Subbagh

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Introduction: Vascular Endothelial Growth Factor receptor (VEGF) is a signal protein produced by cells that stimulates vasculogenesis to create new blood vessels. VEGF family binds to three trans-membrane tyrosine kinase receptors,Dihydrofolate reductase (DHFR) is an enzyme of crucial importance in medicinal chemistry. DHFR catalyzes the reduction 7,8 dihydro-folate to tetrahydrofolate and intimately couples with thymidylate synthase which is a pivotal enzyme that catalysis the reductive methylation of deoxyuridine monophosphate (dUMP) to deoxythymidine monophosphate (dTMP) utilizing N5,N10-methylene tetrahydrofolate as a cofactor which functions as the source of the methyl group. Purpose: Novel substituted Thiazole agents were designed as DHFR and VEGF-TK inhibitors with increased synergistic activity and decreased side effects. Methods: Five series of compounds were designed with a rational that mimic the pharmacophoric features present in the reported active compounds that target DHFR & VEGFR. These molecules were docked against Methotrexate & Sorafenib as controls. An in silico ADMET study was also performed to validate the bioavailability of the newly designed compounds. The in silico molecular docking & ADMET study were also applied to the non-classical antifolates for comparison. The interaction energy comparable to that of MTX for DHFRI and Sorafenib for VEGF-TKI activity were recorded. Results: Compound 5 exhibited the highest interaction energy when docked against Sorafenib, While Compound 9 showed the highest interaction energy when docked against MTX with the perfect binding mode. Comparable results were also obtained for the ADMET study. Most of the compounds showed absorption within (95-99) zone which varies according to the type of substituents. Conclusions: The Substituted Thiazole Analogues could be a suitable template for antitumor drugs that possess enhanced bioavailability and act as DHFR and VEGF-TK inhibitors.

Keywords: anti-tumor agents, DHFR, drug design, molecular modeling, VEGFR-TKIs

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323 Drug Design Modelling and Molecular Virtual Simulation of an Optimized BSA-Based Nanoparticle Formulation Loaded with Di-Berberine Sulfate Acid Salt

Authors: Eman M. Sarhan, Doaa A. Ghareeb, Gabriella Ortore, Amr A. Amara, Mohamed M. El-Sayed

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Drug salting and nanoparticle-based drug delivery formulations are considered to be an effective means for rendering the hydrophobic drugs’ nano-scale dispersion in aqueous media, and thus circumventing the pitfalls of their poor solubility as well as enhancing their membrane permeability. The current study aims to increase the bioavailability of quaternary ammonium berberine through acid salting and biodegradable bovine serum albumin (BSA)-based nanoparticulate drug formulation. Berberine hydroxide (BBR-OH) that was chemically synthesized by alkalization of the commercially available berberine hydrochloride (BBR-HCl) was then acidified to get Di-berberine sulfate (BBR)₂SO₄. The purified crystals were spectrally characterized. The desolvation technique was optimized for the preparation of size-controlled BSA-BBR-HCl, BSA-BBR-OH, and BSA-(BBR)₂SO₄ nanoparticles. Particle size, zeta potential, drug release, encapsulation efficiency, Fourier transform infrared spectroscopy (FTIR), tandem MS-MS spectroscopy, energy-dispersive X-ray spectroscopy (EDX), scanning and transmitting electron microscopic examination (SEM, TEM), in vitro bioactivity, and in silico drug-polymer interaction were determined. BSA (PDB ID; 4OR0) protonation state at different pH values was predicted using Amber12 molecular dynamic simulation. Then blind docking was performed using Lamarkian genetic algorithm (LGA) through AutoDock4.2 software. Results proved the purity and the size-controlled synthesis of berberine-BSA-nanoparticles. The possible binding poses, hydrophobic and hydrophilic interactions of berberine on BSA at different pH values were predicted. Antioxidant, anti-hemolytic, and cell differentiated ability of tested drugs and their nano-formulations were evaluated. Thus, drug salting and the potentially effective albumin berberine nanoparticle formulations can be successfully developed using a well-optimized desolvation technique and exhibiting better in vitro cellular bioavailability.

Keywords: berberine, BSA, BBR-OH, BBR-HCl, BSA-BBR-HCl, BSA-BBR-OH, (BBR)₂SO₄, BSA-(BBR)₂SO₄, FTIR, AutoDock4.2 Software, Lamarkian genetic algorithm, SEM, TEM, EDX

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322 Research of the Load Bearing Capacity of Inserts Embedded in CFRP under Different Loading Conditions

Authors: F. Pottmeyer, M. Weispfenning, K. A. Weidenmann

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Continuous carbon fiber reinforced plastics (CFRP) exhibit a high application potential for lightweight structures due to their outstanding specific mechanical properties. Embedded metal elements, so-called inserts, can be used to join structural CFRP parts. Drilling of the components to be joined can be avoided using inserts. In consequence, no bearing stress is anticipated. This is a distinctive benefit of embedded inserts, since continuous CFRP have low shear and bearing strength. This paper aims at the investigation of the load bearing capacity after preinduced damages from impact tests and thermal-cycling. In addition, characterization of mechanical properties during dynamic high speed pull-out testing under different loading velocities was conducted. It has been shown that the load bearing capacity increases up to 100% for very high velocities (15 m/s) in comparison with quasi-static loading conditions (1.5 mm/min). Residual strength measurements identified the influence of thermal loading and preinduced mechanical damage. For both, the residual strength was evaluated afterwards by quasi-static pull-out tests. Taking into account the DIN EN 6038 a high decrease of force occurs at impact energy of 16 J with significant damage of the laminate. Lower impact energies of 6 J, 9 J, and 12 J do not decrease the measured residual strength, although the laminate is visibly damaged - distinguished by cracks on the rear side. To evaluate the influence of thermal loading, the specimens were placed in a climate chamber and were exposed to various numbers of temperature cycles. One cycle took 1.5 hours from -40 °C to +80 °C. It could be shown that already 10 temperature cycles decrease the load bearing capacity up to 20%. Further reduction of the residual strength with increasing number of thermal cycles was not observed. Thus, it implies that the maximum damage of the composite is already induced after 10 temperature cycles.

Keywords: composite, joining, inserts, dynamic loading, thermal loading, residual strength, impact

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321 Treating Complex Pain and Addictions with Bioelectrode Therapy: An Acupuncture Point Stimulus Method for Relieving Human Suffering

Authors: Les Moncrieff

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In a world awash with potent opioids flaming an international crisis, the need to explore safe alternatives has never been more urgent. Bio-electrode Therapy is a novel adjunctive treatment method for relieving acute opioid withdrawal symptoms and many types of complex acute and chronic pain (often the underlying cause of opioid dependence). By combining the science of developmental bioelectricity with Traditional Chinese Medicine’s theory of meridians, rapid relief from pain is routinely being achieved in the clinical setting. Human body functions are dependent on electrical factors, and acupuncture points on the body are known to have higher electrical conductivity than surrounding skin tissue. When tiny gold- and silver-plated electrodes are secured to the skin at specific acupuncture points using established Chinese Medicine principles and protocols, an enhanced microcurrent and electrical field are created between the electrodes, influencing the entire meridian and connecting meridians. No external power source or electrical devices are required. Endogenous DC electric fields are an essential fundamental component for development, regeneration, and wound healing. Disruptions in the normal ion-charge in the meridians and circulation of blood will manifest as pain and development of disease. With the application of these simple electrodes (gold acting as cathode and silver as anode) according to protocols, the resulting microcurrent is directed along the selected meridians to target injured or diseased organs and tissues. When injured or diseased cells have been stimulated by the microcurrent and electrical fields, the permeability of the cell membrane is affected, resulting in an immediate relief of pain, a rapid balancing of positive and negative ions (sodium, potassium, etc.) in the cells, the restoration of intracellular fluid levels, replenishment of electrolyte levels, pH balance, removal of toxins, and a re-establishment of homeostasis.

Keywords: bioelectricity, electrodes, electrical fields, acupuncture meridians, complex pain, opioid withdrawal management

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320 Undersea Communications Infrastructure: Risks, Opportunities, and Geopolitical Considerations

Authors: Lori W. Gordon, Karen A. Jones

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Today’s high-speed data connectivity depends on a vast global network of infrastructure across space, air, land, and sea, with undersea cable infrastructure (UCI) serving as the primary means for intercontinental and ‘long-haul’ communications. The UCI landscape is changing and includes an increasing variety of state actors, such as the growing economies of Brazil, Russia, India, China, and South Africa. Non-state commercial actors, such as hyper-scale content providers including Google, Facebook, Microsoft, and Amazon, are also seeking to control their data and networks through significant investments in submarine cables. Active investments by both state and non-state actors will invariably influence the growth, geopolitics, and security of this sector. Beyond these hyper-scale content providers, there are new commercial satellite communication providers. These new players include traditional geosynchronous (GEO) satellites that offer broad coverage, high throughput GEO satellites offering high capacity with spot beam technology, low earth orbit (LEO) ‘mega constellations’ – global broadband services. And potential new entrants such as High Altitude Platforms (HAPS) offer low latency connectivity, LEO constellations offer high-speed optical mesh networks, i.e., ‘fiber in the sky.’ This paper focuses on understanding the role of submarine cables within the larger context of the global data commons, spanning space, terrestrial, air, and sea networks, including an analysis of national security policy and geopolitical implications. As network operators and commercial and government stakeholders plan for emerging technologies and architectures, hedging risks for future connectivity will ensure that our data backbone will be secure for years to come.

Keywords: communications, global, infrastructure, technology

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319 Cocoon Characterization of Sericigenous Insects in North-East India and Prospects

Authors: Tarali Kalita, Karabi Dutta

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The North Eastern Region of India, with diverse climatic conditions and a wide range of ecological habitats, makes an ideal natural abode for a good number of silk-producing insects. Cocoon is the economically important life stage from where silk of economic importance is obtained. In recent years, silk-based biomaterials have gained considerable attention, which is dependent on the structure and properties of the silkworm cocoons as well as silk yarn. The present investigation deals with the morphological study of cocoons, including cocoon color, cocoon size, shell weight and shell ratio of eleven different species of silk insects collected from different regions of North East India. The Scanning Electron Microscopic study and X-ray photoelectron spectroscopy were performed to know the arrangement of silk threads in cocoons and the atomic elemental analysis, respectively. Further, collected cocoons were degummed and reeled/spun on a reeling machine or spinning wheel to know the filament length, linear density and tensile strength by using Universal Testing Machine. The study showed significant variation in terms of cocoon color, cocoon shape, cocoon weight and filament packaging. XPS analysis revealed the presence of elements (Mass %) C, N, O, Si and Ca in varying amounts. The wild cocoons showed the presence of Calcium oxalate crystals which makes the cocoons hard and needs further treatment to reel. In the present investigation, the highest percentage of strain (%) and toughness (g/den) were observed in Antheraea assamensis, which implies that the muga silk is a more compact packing of molecules. It is expected that this study will be the basis for further biomimetic studies to design and manufacture artificial fiber composites with novel morphologies and associated material properties.

Keywords: cocoon characterization, north-east India, prospects, silk characterization

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318 Crossing of the Intestinal Barrier Thanks to Targeted Biologics: Nanofitins

Authors: Solene Masloh, Anne Chevrel, Maxime Culot, Leonardo Scapozza, Magali Zeisser-Labouebe

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The limited stability of clinically proven therapeutic antibodies limits their administration by the parenteral route. However, oral administration remains the best alternative as it is the most convenient and less invasive one. Obtaining a targeted treatment based on biologics, which can be orally administered, would, therefore, be an ideal situation to improve patient adherence and compliance. Nevertheless, the delivery of macromolecules through the intestine remains challenging because of their sensitivity to the harsh conditions of the gastrointestinal tract and their low permeability across the intestinal mucosa. To address this challenge, this project aims to demonstrate that targeting receptor-mediated endocytosis followed by transcytosis could maximize the intestinal uptake and transport of large molecules, such as Nanofitins. These affinity proteins of 7 kDa with binding properties similar to antibodies have already demonstrated retained stability in the digestive tract and local efficiency. However, their size does not allow passive diffusion through the intestinal barrier. Nanofitins having a controlled affinity for membrane receptors involved in the transcytosis mechanism used naturally for the transport of large molecules in humans were generated. Proteins were expressed using ribosome display and selected based on affinity to the targeted receptor and other characteristics. Their uptake and transport ex vivo across viable porcine intestines were investigated using an Ussing chambers system. In this paper, we will report the results achieved while addressing the different challenges linked to this study. To validate the ex vivo model, first, we proved the presence of the receptors targeted in humans on the porcine intestine. Then, after the identification of an optimal way of detection of Nanofitins, transport experiments were performed on porcine intestines with viability followed during the time of the experiment. The results, showing that the physiological process of transcytosis is capable of being triggered by the binding of Nanofitins on their target, will be reported here. In conclusion, the results show that Nanofitins can be transported across the intestinal barrier by triggering the receptor-mediated transcytosis and that the ex vivo model is an interesting technique to assess biologics absorption through the intestine.

Keywords: ex-vivo, Nanofitins, oral administration, transcytosis

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317 Transformation of ectA Gene From Halomonas elongata in Tomato Plant

Authors: Narayan Moger, Divya B., Preethi Jambagi, Krishnaveni C. K., Apsana M. R., B. R. Patil, Basvaraj Bagewadi

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Salinity is one of the major threats to world food security. Considering the requirement for salt tolerant crop plants in the present study was undertaken to clone and transferred the salt tolerant ectA gene from marine ecosystem into agriculture crop system to impart salinity tolerance. Ectoine is the compatible solute which accumulates in the cell membrane, is known to be involved in salt tolerance activity in most of the Halophiles. The present situation is insisting to development of salt tolerant transgenic lines to combat abiotic stress. In this background, the investigation was conducted to develop transgenic tomato lines by cloning and transferring of ectA gene is an ectoine derivative capable of enzymatic action for the production of acetyl-diaminobutyric acid. The gene ectA is involved in maintaining the osmotic balance of plants. The PCR amplified ectA gene (579bp) was cloned into T/A cloning vector (pTZ57R/T). The construct pDBJ26 containing ectA gene was sequenced by using gene specific forward and reverse primers. Sequence was analyzed using BLAST algorithm to check similarity of ectA gene with other isolates. Highest homology of 99.66 per cent was found with ectA gene sequences of isolates Halomonas elongata with the available sequence information in NCBI database. The ectA gene was further sub cloned into pRI101-AN plant expression vector and transferred into E. coli DH5α for its maintenance. Further pDNM27 was mobilized into A. tumefaciens LBA4404 through tri-parental mating system. The recombinant Agrobacterium containing pDNM27 was transferred into tomato plants through In planta plant transformation method. Out of 300 seedlings, co-cultivated only twenty-seven plants were able to well establish under the greenhouse condition. Among twenty-seven transformants only twelve plants showed amplification with gene specific primers. Further work must be extended to evaluate the transformants at T1 and T2 generations for ectoine accumulation, salinity tolerance, plant growth and development and yield.

Keywords: salinity, computable solutes, ectA, transgenic, in planta transformation

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316 Assessment of Zinc Content in Nuts by Atomic Absorption Spectrometry Method

Authors: Katarzyna Socha, Konrad Mielcarek, Grzegorz Kangowski, Renata Markiewicz-Zukowska, Anna Puscion-Jakubik, Jolanta Soroczynska, Maria H. Borawska

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Nuts have high nutritional value. They are a good source of polyunsaturated fatty acids, dietary fiber, vitamins (B₁, B₆, E, K) and minerals: magnesium, selenium, zinc (Zn). Zn is an essential element for proper functioning and development of human organism. Due to antioxidant and anti-inflammatory properties, Zn has an influence on immunological and central nervous system. It also affects proper functioning of reproductive organs and has beneficial impact on the condition of skin, hair, and nails. The objective of this study was estimation of Zn content in edible nuts. The research material consisted of 10 types of nuts, 12 samples of each type: almonds, brazil nuts, cashews, hazelnuts, macadamia nuts, peanuts, pecans, pine nuts, pistachios, and walnuts. The samples of nuts were digested in concentrated nitric acid using microwave mineralizer (Berghof, Germany). The concentration of Zn was determined by flame atomic absorption spectrometry method with Zeeman background correction (Hitachi, Japan). The accuracy of the method was verified on certified reference material: Simulated Diet D. The statistical analysis was performed using Statistica v. 13.0 software. For comparison between the groups, t-Student test was used. The highest content of Zn was shown in pine nuts and cashews: 78.57 ± 21.9, 70.02 ± 10,2 mg/kg, respectively, significantly higher than in other types of nuts. The lowest content of Zn was found in macadamia nuts: 16.25 ± 4.1 mg/kg. The consumption of a standard 42-gram portion of almonds, brazil nuts, cashews, peanuts, pecans, and pine nuts covers the daily requirement for Zn above 15% of recommended daily allowances (RDA) for women, while in the case of men consumption all of the above types of nuts, except peanuts. Selected types of nuts can be a good source of Zn in the diet.

Keywords: atomic absorption spectrometry, microelement, nuts, zinc

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315 Identification of Nutrient Sensitive Signaling Pathways via Analysis of O-GlcNAcylation

Authors: Michael P. Mannino, Gerald W. Hart

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The majority of glucose metabolism proceeds through glycolytic pathways such as glycolysis or pentose phosphate pathway, however, about 5% is shunted through the hexosamine biosynthetic pathway, producing uridine diphosphate N-acetyl glucosamine (UDP-GlcNAc). This precursor can then be incorporated into complex oligosaccharides decorating the cell surface or remain as an intracellular post-translational-modification (PTM) of serine/threonine residues (O-GlcNAcylation, OGN), which has been identified on over 4,000 cytosolic or nuclear proteins. Intracellular OGN has major implications on cellularprocesses, typically by modulating protein localization, protein-protein interactions, protein degradation, and gene expression. Additionally, OGN is known to have an extensive cross-talk with phosphorylation, be in a competitive or cooperative manner. Unlike other PTMs there are only two cycling enzymes that are capable of adding or removing the GlcNAc moiety, O-linked N-aceytl glucosamine Transferase (OGT) and O-linked N-acetyl glucoamidase (OGA), respectively. The activity of OGT has been shown to be sensitive to cellular UDP-GlcNAc levels, even changing substrate affinity. Owing to this and that the concentration of UDP-GlcNAc is related to the metabolisms of glucose, amino acid, fatty acid, and nucleotides, O-GlcNAc is often referred to as a nutrient sensing rheostat. Indeed OGN is known to regulate several signaling pathways as a result of nutrient levels, such as insulin signaling. Dysregulation of OGN is associated with several disease states such as cancer, diabetes, and neurodegeneration. Improvements in glycomics over the past 10-15 years has significantly increased the OGT substrate pool, suggesting O-GlcNAc’s involvement in a wide variety of signaling pathways. However, O-GlcNAc’s role at the receptor level has only been identified in a case-by-case basis of known pathways. Examining the OGN of the plasma membrane (PM) may better focus our understanding of O-GlcNAc-effected signaling pathways. In this current study, PM fractions were isolated from several cell types via ultracentrifugation, followed by purification and MS/MS analysis in several cell lines. This process was repeated with or without OGT/OGA inhibitors or with increased/decreased glucose levels in media to ascertain the importance of OGN. Various pathways are followed up on in more detailed studies employing methods to localize OGN at the PM specifically.

Keywords: GlcNAc, nutrient sensitive, post-translational-modification, receptor

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314 Molecular Insights into the 5α-Reductase Inhibitors: Quantitative Structure Activity Relationship, Pre-Absorption, Distribution, Metabolism, and Excretion and Docking Studies

Authors: Richa Dhingra, Monika, Manav Malhotra, Tilak Raj Bhardwaj, Neelima Dhingra

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5-Alpha-reductases (5AR), a membrane bound, NADPH dependent enzyme and convert male hormone testosterone (T) into more potent androgen dihydrotestosterone (DHT). DHT is the required for the development and function of male sex organs, but its overproduction has been found to be associated with physiological conditions like Benign Prostatic Hyperplasia (BPH). Thus the inhibition of 5ARs could be a key target for the treatment of BPH. In present study, 2D and 3D Quantitative Structure Activity Relationship (QSAR) pharmacophore models have been generated for 5AR based on known inhibitory concentration (IC₅₀) values with extensive validations. The four featured 2D pharmacophore based PLS model correlated the topological interactions (–OH group connected with one single bond) (SsOHE-index); semi-empirical (Quadrupole2) and physicochemical descriptors (Mol. wt, Bromines Count, Chlorines Count) with 5AR inhibitory activity, and has the highest correlation coefficient (r² = 0.98, q² =0.84; F = 57.87, pred r² = 0.88). Internal and external validation was carried out using test and proposed set of compounds. The contribution plot of electrostatic field effects and steric interactions generated by 3D-QSAR showed interesting results in terms of internal and external predictability. The well validated 2D Partial Least Squares (PLS) and 3D k-nearest neighbour (kNN) models were used to search novel 5AR inhibitors with different chemical scaffold. To gain more insights into the molecular mechanism of action of these steroidal derivatives, molecular docking and in silico absorption, distribution, metabolism, and excretion (ADME) studies were also performed. Studies have revealed the hydrophobic and hydrogen bonding of the ligand with residues Alanine (ALA) 63A, Threonine (THR) 60A, and Arginine (ARG) 456A of 4AT0 protein at the hinge region. The results of QSAR, molecular docking, in silico ADME studies provide guideline and mechanistic scope for the identification of more potent 5-Alpha-reductase inhibitors (5ARI).

Keywords: 5α-reductase inhibitor, benign prostatic hyperplasia, ligands, molecular docking, QSAR

Procedia PDF Downloads 158
313 Preparation and Characterization of CO-Tolerant Electrocatalyst for PEM Fuel Cell

Authors: Ádám Vass, István Bakos, Irina Borbáth, Zoltán Pászti, István Sajó, András Tompos

Abstract:

Important requirements for the anode side electrocatalysts of polymer electrolyte membrane (PEM) fuel cells are CO-tolerance, stability and corrosion resistance. Carbon is still the most common material for electrocatalyst supports due to its low cost, high electrical conductivity and high surface area, which can ensure good dispersion of the Pt. However, carbon becomes degraded at higher potentials and it causes problem during application. Therefore it is important to explore alternative materials with improved stability. Molybdenum-oxide can improve the CO-tolerance of the Pt/C catalysts, but it is prone to leach in acidic electrolyte. The Mo was stabilized by isovalent substitution of molybdenum into the rutile phase titanium-dioxide lattice, achieved by a modified multistep sol-gel synthesis method optimized for preparation of Ti0.7Mo.3O2-C composite. High degree of Mo incorporation into the rutile lattice was developed. The conductivity and corrosion resistance across the anticipated potential/pH window was ensured by mixed oxide – activated carbon composite. Platinum loading was carried out using NaBH4 and ethylene glycol; platinum content was 40 wt%. The electrocatalyst was characterized by both material investigating methods (i.e. XRD, TEM, EDS, XPS techniques) and electrochemical methods (cyclic-voltammetry, COads stripping voltammetry, hydrogen oxidation reaction on rotating disc electrode). The electrochemical activity of the sample was compared to commercial 40 wt% Pt/C (Quintech) and PtRu/C (Quintech, Pt= 20 wt%, Ru= 10 wt%) references. Enhanced CO tolerance of the electrocatalyst prepared using the Ti0.7Mo.3O2-C composite material was evidenced by the appearance of a CO-oxidation related 'pre-peak' and by the pronounced shift of the maximum of the main CO oxidation peak towards less positive potential compared to Pt/C. Fuel cell polarization measurements were also carried out using Bio-Logic and Paxitech FCT-150S test device. All details on the design, preparation, characterization and testing by both electrochemical measurements and fuel cell test device of electrocatalyst supported on Ti0.7Mo.3O2-C composite material will be presented and discussed.

Keywords: anode electrocatalyst, composite material, CO-tolerance, TiMoOx

Procedia PDF Downloads 296
312 Effect of Steam Explosion of Crop Residues on Chemical Compositions and Efficient Energy Values

Authors: Xin Wu, Yongfeng Zhao, Qingxiang Meng

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In China, quite low proportion of crop residues were used as feedstuff because of its poor palatability and low digestibility. Steam explosion is a physical and chemical feed processing technology which has great potential to improve sapidity and digestibility of crop residues. To investigate the effect of the steam explosion on chemical compositions and efficient energy values, crop residues (rice straw, wheat straw and maize stover) were processed by steam explosion (steam temperature 120-230°C, steam pressure 2-26kg/cm², 40min). Steam-exploded crop residues were regarded as treatment groups and untreated ones as control groups, nutritive compositions were analyzed and effective energy values were calculated by prediction model in INRA (1988, 2010) for both groups. Results indicated that the interaction between treatment and variety has a significant effect on chemical compositions of crop residues. Steam explosion treatment of crop residues decreased neutral detergent fiber (NDF) significantly (P < 0.01), and compared with untreated material, NDF content of rice straw, wheat straw, and maize stover lowered 21.46%, 32.11%, 28.34% respectively. Acid detergent lignin (ADL) of crop residues increased significantly after the steam explosion (P < 0.05). The content of crude protein (CP), ether extract (EE) and Ash increased significantly after steam explosion (P < 0.05). Moreover, predicted effective energy values of each steam-exploded residue were higher than that of untreated ones. The digestible energy (DE), metabolizable energy (ME), net energy for maintenance (NEm) and net energy for gain (NEg)of steam-exploded rice straw were 3.06, 2.48, 1.48and 0.29 MJ/kg respectively and increased 46.21%, 46.25%, 49.56% and 110.92% compared with untreated ones(P < 0.05). Correspondingly, the energy values of steam-exploded wheat straw were 2.18, 1.76, 1.03 and 0.15 MJ/kg, which were 261.78%, 261.29%, 274.59% and 1014.69% greater than that of wheat straw (P < 0.05). The above predicted energy values of steam exploded maize stover were 5.28, 4.30, 2.67 and 0.82 MJ/kg and raised 109.58%, 107.71%, 122.57% and 332.64% compared with the raw material(P < 0.05). In conclusion, steam explosion treatment could significantly decrease NDF content, increase ADL, CP, EE, Ash content and effective energy values of crop residues. The effect of steam explosion was much more obvious for wheat straw than the other two kinds of residues under the same condition.

Keywords: chemical compositions, crop residues, efficient energy values, steam explosion

Procedia PDF Downloads 245
311 Determination of the Volatile Organic Compounds, Antioxidant and Antimicrobial Properties of Microwave-Assisted Green Extracted Ficus Carica Linn Leaves

Authors: Pelin Yilmaz, Gizemnur Yildiz Uysal, Elcin Demirhan, Belma Ozbek

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The edible fig plant, Ficus carica Linn, belongs to the Moraceae family, and the leaves are mainly considered agricultural waste after harvesting. It has been demonstrated in the literature that fig leaves contain appealing properties such as high vitamins, fiber, amino acids, organic acids, and phenolic or flavonoid content. The extraction of these valuable products has gained importance. Microwave-assisted extraction (MAE) is a method using microwave energy to heat the solvents, thereby transferring the bioactive compounds from the sample to the solvent. The main advantage of the MAE is the rapid extraction of bioactive compounds. In the present study, the MAE was applied to extract the bioactive compounds from Ficus carica L. leaves, and the effect of microwave power (180-900 W), extraction time (60-180 s), and solvent to sample amount (mL/g) (10-30) on the antioxidant property of the leaves. Then, the volatile organic component profile was determined at the specified extraction point. Additionally, antimicrobial studies were carried out to determine the minimum inhibitory concentration of the microwave-extracted leaves. As a result, according to the data obtained from the experimental studies, the highest antimicrobial properties were obtained under the process parameters such as 540 W, 180 s, and 20 mL/g concentration. The volatile organic compound profile showed that isobergapten, which belongs to the furanocoumarins family exhibiting anticancer, antioxidant, and antimicrobial activity besides promoting bone health, was the main compound. Acknowledgments: This work has been supported by Yildiz Technical University Scientific Research Projects Coordination Unit under project number FBA-2021-4409. The authors would like to acknowledge the financial support from Tubitak 1515 - Frontier R&D Laboratory Support Programme.

Keywords: Ficus carica Linn leaves, volatile organic component, GC-MS, microwave extraction, isobergapten, antimicrobial

Procedia PDF Downloads 73
310 Comparison of Physical and Chemical Effects on Senescent Cells

Authors: Svetlana Guryeva, Inna Kornienko, Andrey Usanov, Dmitry Usanov, Elena Petersen

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Every day cells in our organism are exposed to various factors: chemical agents, reactive oxygen species, ionizing radiation, and others. These factors can cause damage to DNA, cellular membrane, intracellular compartments, and proteins. The fate of cells depends on the exposure intensity and duration. The prolonged and intense exposure causes the irreversible damage accumulation, which triggers the permanent cell cycle arrest (cellular senescence) or cell death programs. In the case of low dose of impacts, it can lead to cell renovation and to cell functional state improvement. Therefore, it is a pivotal question to investigate the factors and doses that result in described positive effects. In order to estimate the influence of different agents, the proliferation index and levels of cell death markers (annexin V/propidium iodide), senescence-associated β-galactosidase, and lipofuscin were measured. The experiments were conducted on primary human fibroblasts of the 8th passage. According to the levels of mentioned markers, these cells were defined as senescent cells. The effect of low-frequency magnetic field was investigated. Different modes of magnetic field exposure were tested. The physical agents were compared with chemical agents: metformin (10 mM) and taurine (0.8 mM and 1.6 mM). Cells were incubating with chemicals for 5 days. The highest decrease in the level of senescence-associated β-galactosidase (21%) and lipofuscin (17%) was observed in the primary senescent fibroblasts after 5 days after double treatments with 48 h intervals with low-frequency magnetic field. There were no significant changes in the proliferation index after magnetic field application. The cytotoxic effect of magnetic field was not observed. The chemical agent taurine (1.6 mM) decreased the level of senescence-associated β-galactosidase (23%) and lipofuscin (22%). Metformin improved the activity of senescence-associated β-galactosidase on 15% and the level of lipofuscin on 19% in this experiment. According to these results, the effect of double treatment with 48 h interval with low-frequency magnetic field and the effect of taurine (1.6 mM) were comparable to the effect of metformin, for which anti-aging properties are proved. In conclusion, this study can become the first step towards creation of the standardized system for the investigation of different effects on senescent cells.

Keywords: biomarkers, magnetic field, metformin, primary fibroblasts, senescence, taurine

Procedia PDF Downloads 273
309 Evaluation of Neonicotinoids Against Sucking Insect Pests of Cotton in Laboratory and Field Conditions

Authors: Muhammad Sufyan, Muhammad D. Gogi, Muhammad Arshad, Ahmad Nawaz, Muhammad Usman

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Cotton (Gossypium hirsutum) universally known as silver fiber and is one of the most important cash crop of Pakistan. A wide array of pests constraints cotton production among which sucking insect pests cause serious losses. Mostly new chemistry insecticides used to control a wide variety of insect pests including sucking insect pests. In the present study efficacy of different neonicotinoids was evaluated against sucking insect pests of cotton in the field and in laboratory for red and dusky cotton bug. The experiment was conducted at Entomology Research Station, University of Agriculture Faisalabad, in a Randomized Complete Block Design (RCBD). Field trial was conducted to evaluate the efficacy of Confidence Ultra (Imidacloprid) 70% SL, Confidor (Imidacloprid) 20% SL, Kendo (Lambda cyhalothrin) 24.7 SC, Actara (Thiamethoxam) 25% WG, Forcast (Tebufenozide+ Emamectin benzoate) 8.8 EW and Timer (Emamectin benzoate) 1.9 EC at their recommended doses. The data was collected on per leaf basis of thrips, aphid, jassid and whitefly before 24 hours of spray. The post treatment data was recorded after 24, 48 and 72 hours. The fresh, non-infested and untreated cotton leaves was collected from the field and brought to the laboratory to assess the efficacy of neonicotinoids against red and dusky cotton bug. After data analysis all the insecticides were found effective against sucking pests. Confidence Ultra was highly effective against the aphid, jassid, and whitefly and gave maximum mortality, while showed non-significant results against thrips. In case of aphid plot which was treated with Kando 24.7 SC showed significant mortality after 72 hours of pesticide application. Similar trends were found in laboratory conditions with all these treatments by making different concentrations and had significant impact on dusky cotton bug and red cotton bug population after 24, 48 and 72 hours after application.

Keywords: cotton, laboratory and field conditions, neonicotinoids, sucking insect pests

Procedia PDF Downloads 237
308 Pale, Soft, Exudative (PSE) Turkey Meat in a Brazilian Commercial Processing Plant

Authors: Danielle C. B. Honorato, Rafael H. Carvalho, Adriana L. Soares, Ana Paula F. R. L. Bracarense, Paulo D. Guarnieri, Massami Shimokomaki, Elza I. Ida

Abstract:

Over the past decade, the Brazilian production of turkey meat increased by more than 50%, indicating that the turkey meat is considered a great potential for the Brazilian economy contributing to the growth of agribusiness at the marketing international scenario. However, significant color changes may occur during its processing leading to the pale, soft and exudative (PSE) appearance on the surface of breast meat due to the low water holding capacity (WHC). Changes in PSE meat functional properties occur due to the myofibrils proteins denaturation caused by a rapid postmortem glycolysis resulting in a rapid pH decline while the carcass temperature is still warm. The aim of this study was to analyze the physical, chemical and histological characteristics of PSE turkey meat obtained from a Brazilian commercial processing plant. The turkey breasts samples were collected (n=64) at the processing line and classified as PSE at L* ≥ 53 value. The pH was also analyzed after L* measurement. In sequence, PSE meat samples were evaluated for WHC, cooking loss (CL), shear force (SF), myofibril fragmentation index (MFI), protein denaturation (PD) and histological evaluation. The abnormal color samples presented lower pH values, 16% lower fiber diameter, 11% lower SF and 2% lower WHC than those classified as normal. The CL, PD and MFI were, respectively, 9%, 18% and 4% higher in PSE samples. The Pearson correlation between the L* values and CL, PD and MFI was positive, while that SF and pH values presented negative correlation. Under light microscopy, a shrinking of PSE muscle cell diameter was approximately 16% shorter in relation to normal samples and an extracellular enlargement of endomysium and perimysium sheaths as the consequence of higher water contents lost as observed previously by lower WHC values. Thus, the results showed that PSE turkey breast meat presented significant changes in their physical, chemical and histological characteristics that may impair its functional properties.

Keywords: functional properties, histological evaluation, meat quality, PSE

Procedia PDF Downloads 453
307 Nonlinear Response of Infinite Beams on a Multilayer Tensionless Extensible Geosynthetic – Reinforced Earth Bed under Moving Load

Authors: K. Karuppasamy

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In this paper analysis of an infinite beam resting on multilayer tensionless extensible geosynthetic reinforced granular fill - poor soil system overlying soft soil strata under moving the load with constant velocity is presented. The beam is subjected to a concentrated load moving with constant velocity. The upper reinforced granular bed is modeled by a rough membrane embedded in Pasternak shear layer overlying a series of compressible nonlinear Winkler springs representing the underlying the very poor soil. The multilayer tensionless extensible geosynthetic layer has been assumed to deform such that at the interface the geosynthetic and the soil have some deformation. Nonlinear behavior of granular fill and the very poor soil has been considered in the analysis by means of hyperbolic constitutive relationships. Governing differential equations of the soil foundation system have been obtained and solved with the help of appropriate boundary conditions. The solution has been obtained by employing finite difference method by means of Gauss-Siedel iterative scheme. Detailed parametric study has been conducted to study the influence of various parameters on the response of soil – foundation system under consideration by means of deflection and bending moment in the beam and tension mobilized in the geosynthetic layer. These parameters include the magnitude of applied load, the velocity of the load, damping, the ultimate resistance of the poor soil and granular fill layer. The range of values of parameters has been considered as per Indian Railways conditions. This study clearly observed that the comparisons of multilayer tensionless extensible geosynthetic reinforcement with poor foundation soil and magnitude of applied load, relative compressibility of granular fill and ultimate resistance of poor soil has significant influence on the response of soil – foundation system. However, for the considered range of velocity, the response has been found to be insensitive towards velocity. The ultimate resistance of granular fill layer has also been found to have no significant influence on the response of the system.

Keywords: infinite beams, multilayer tensionless extensible geosynthetic, granular layer, moving load and nonlinear behavior of poor soil

Procedia PDF Downloads 434
306 Preliminary Composite Overwrapped Pressure Vessel Design for Hydrogen Storage Using Netting Analysis and American Society of Mechanical Engineers Section X

Authors: Natasha Botha, Gary Corderely, Helen M. Inglis

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With the move to cleaner energy applications the transport industry is working towards on-board hydrogen, or compressed natural gas-fuelled vehicles. A popular method for storage is to use composite overwrapped pressure vessels (COPV) because of their high strength to weight ratios. The proper design of these COPVs are according to international standards; this study aims to provide a preliminary design for a 350 Bar Type IV COPV (i.e. a polymer liner with a composite overwrap). Netting analysis, a popular analytical approach, is used as a first step to generate an initial design concept for the composite winding. This design is further improved upon by following the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel standards, Section X: Fibre-reinforced composite pressure vessels. A design program based on these two approaches is developed using Python. A numerical model of a burst test simulation is developed based on the two approaches and compared. The results indicate that the netting analysis provides a good preliminary design, while the ASME-based design is more robust and accurate as it includes a better approximation of the material behaviour. Netting analysis is an easy method to follow when considering an initial concept design for the composite winding when not all the material characteristics are known. Once these characteristics have been fully defined with experimental testing, an ASME-based design should always be followed to ensure that all designs conform to international standards and practices. Future work entails more detailed numerical testing of the design for improvement, this will include the boss design. Once finalised prototype manufacturing and experimental testing will be conducted, and the results used to improve on the COPV design.

Keywords: composite overwrapped pressure vessel, netting analysis, design, American Society of Mechanical Engineers section x, fiber-reinforced, hydrogen storage

Procedia PDF Downloads 245
305 Coating of Cotton with Blend of Natural Rubber and Chloroprene Containing Ammonium Acetate for Producing Moisture Vapour Permeable Waterproof Fabric

Authors: Debasish Das, Mainak Mitra, A.Chaudhuri

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For the purpose of producing moisture vapor permeable waterproof cotton fabric to be used for protective apparel against rain, cotton fabric was coated with the blend of natural rubber and chloroprene rubber containing ammonium acetate as the water-soluble salt, employing a calendar coating technique. Rubber formulations also contained filler, homogenizer, and a typical sulphur curing system. Natural rubber and chloroprene blend in the blend ratio of 30: 70, containing 25 parts of sodium acetate per hundred parts of rubber was coated on the fabric. The coated fabric was vulcanized thereafter at 140oC for 3 h. Coated and vulcanized fabric was subsequently dipped in water for 45 min, followed by drying in air. Such set of treatments produced optimum results. Coated, vulcanized, washed and dried cotton fabric showed optimum developments in the property profiles in respect of waterproofness, breathability as revealed by moisture vapor transmission rate, coating adhesion, tensile properties, abrasion resistance, flex endurance and fire retardancy. Incorporation of highly water-soluble ammonium acetate salt in the coating formulation and their subsequent removal from vulcanized coated layer affected by post washing in consequent to dipping in the water-bath produced holes of only a few microns in the coating matrix of the fabric. Such microporous membrane formed on the cotton fabric allowed only transportation of moisture vapor through them, giving a moisture vapor transmission rate of 3734 g/m2/24h, while acting as a barrier for large liquid water droplet resisting 120cm of the water column in the hydrostatic water-head tester, rendering the coated cotton fabric waterproof. Examination of surface morphology of vulcanized coating by scanning electron microscopy supported the mechanism proposed for development of breathable waterproof layer on cotton fabric by the process employed above. Such process provides an easy and cost-effective route for achieving moisture vapor permeable waterproof cotton.

Keywords: moisture vapour permeability, waterproofness, chloroprene, calendar coating, coating adhesion, fire retardancy

Procedia PDF Downloads 251
304 Harnessing the Power of Mixed Ligand Complexes: Enhancing Antimicrobial Activities with Thiosemicarbazones

Authors: Sakshi Gupta, Seema Joshi

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Thiosemicarbazones (TSCs) have garnered significant attention in coordination chemistry due to their versatile coordination modes and pharmacological properties. Mixed ligand complexes of TSCs represent a promising area of research, offering enhanced antimicrobial activities compared to their parent compounds. This review provides an overview of the synthesis, characterization, and antimicrobial properties of mixed ligand complexes incorporating thiosemicarbazones. The synthesis of mixed ligand complexes typically involves the reaction of a metal salt with TSC ligands and additional ligands, such as nitrogen- or oxygen-based ligands. Various transition metals, including copper, nickel, and cobalt, have been employed to form mixed ligand complexes with TSCs. Characterization techniques such as spectroscopy, X-ray crystallography, and elemental analysis are commonly utilized to confirm the structures of these complexes. One of the key advantages of mixed ligand complexes is their enhanced antimicrobial activity compared to pure TSC compounds. The synergistic effect between the TSC ligands and additional ligands contributes to increased efficacy, possibly through improved metal-ligand interactions or enhanced membrane permeability. Furthermore, mixed ligand complexes offer the potential for selective targeting of microbial species while minimizing toxicity to mammalian cells. This selectivity arises from the specific interactions between the metal center, TSC ligands, and biological targets within microbial cells. Such targeted antimicrobial activity is crucial for developing effective treatments with minimal side effects. Moreover, the versatility of mixed ligand complexes allows for the design of tailored antimicrobial agents with optimized properties. By varying the metal ion, TSC ligands, and additional ligands, researchers can fine-tune the physicochemical properties and biological activities of these complexes. This tunability opens avenues for the development of novel antimicrobial agents with improved efficacy and reduced resistance. In conclusion, mixed ligand complexes of thiosemicarbazones represent a promising class of compounds with potent antimicrobial activities. Further research in this field holds great potential for the development of novel therapeutic agents to combat microbial infections effectively.

Keywords: metal complex, thiosemicarbazones, mixed ligand, selective targeting, antimicrobial activity

Procedia PDF Downloads 54
303 Novel Nickel Complex Compound Reactivates the Apoptotic Network, Cell Cycle Arrest and Cytoskeletal Rearrangement in Human Colon and Breast Cancer Cells

Authors: Nima Samie, Batoul Sadat Haerian, Sekaran Muniandy, M. S. Kanthimathi

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Colon and breast cancers are categorized as the most prevalent types of cancer worldwide. Recently, the broad clinical application of metal complex compounds has led to the discovery of potential therapeutic drugs. The aim of this study was to evaluate the cytotoxic action of a selected nickel complex compound (NCC) against human colon and breast cancer cells. In this context, we determined the potency of the compound in the induction of apoptosis, cell cycle arrest, and cytoskeleton rearrangement. HT-29, WiDr, CCD-18Co, MCF-7 and Hs 190.T cell lines were used to determine the IC50 of the compound using the MTT assay. Analysis of apoptosis was carried out using immunofluorescence, acridine orange/ propidium iodide double staining, Annexin-V-FITC assay, evaluation of the translocation of NF-kB, oxygen radical antioxidant capacity, quenching of reactive oxygen species content , measurement of LDH release, caspase-3/-7, -8 and -9 assays and western blotting. The cell cycle arrest was examined using flowcytometry and gene expression was assessed using qPCR array. Results showed that our nickel complex compound displayed a potent suppressive effect on HT-29, WiDr, MCF-7 and Hs 190.T after 24 h of treatment with IC50 value of 2.02±0.54, 2.13±0.65, 3.76±015 and 3.14±0.45 µM respectively. This cytotoxic effect on normal cells was insignificant. Dipping in the mitochondrial membrane potential and increased release of cytochrome c from the mitochondria indicated induction of the intrinsic apoptosis pathway by the nickel complex compound. Activation of this pathway was further evidenced by significant activation of caspase 9 and 3/7.The nickel complex compound (NCC) was also shown activate the extrinsic pathways of apoptosis by activation of caspase-8 which is linked to the suppression of NF-kB translocation to the nucleus. Cell cycle arrest in the G1 phase and up-regulation of glutathione reductase, based on excessive ROS production were also observed. The results of this study suggest that the nickel complex compound is a potent anti-cancer agent inducing both intrinsic and extrinsic pathways as well as cell cycle arrest in colon and breast cancer cells.

Keywords: nickel complex, apoptosis, cytoskeletal rearrangement, colon cancer, breast cancer

Procedia PDF Downloads 309
302 Siderophore Receptor Protein from Klebsiella pneumoniae as a Promising Immunogen for Serotype-Independent Therapeutic Lead Development

Authors: Sweta Pandey, Samridhi Dhyani, Susmita Chaudhuri

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Klebsiella pneumoniae causes a wide range of infections, including urinary tract infections, sepsis, bacteremia, pneumonia, and liver abscesses. The emergence of multi-drug resistance in this bacterium led to a major setback for clinical management. WHO also endorsed a need for finding alternative therapy to antibiotics for the treatment of these infections. Development of vaccines and passive antibody therapy has been proven as a potent alternative to antibiotics in the case of MDR, XDR, and PDR Klebsiella infections. Siderophore receptors have been demonstrated to be overexpressed for the internalization of iron siderophore complexes during infections in most Gram-negative bacteria. For the present study, immune response to siderophore receptors to establish this protein as a potential immunogen for the development of therapeutic leads was explored. Clinical strains of Klebsiella pneumoniae were grown in iron-deficient conditions, and the iron-regulated outer membrane proteins were extracted and characterized through mass spectrometry for specific identification. The gene for identified protein was cloned in pET- 28a vector and expressed in E. coli. The native protein and the recombinant protein were isolated and purified and used as antigens for the generation of immune response in BALB/c mice. The native protein of Klebsiella pneumoniae grown in iron-deficient conditions was identified as FepA (Ferrienterobactin receptor) and other siderophore receptors. This 80 kDa protein generated an immune response in BALB/c mice. The antiserum from mice after subsequent booster doses was collected and showed binding with FepA protein in western blot and phagocytic uptake of the K. pneumoniae in the presence antiserum from immunized mice also observed from the animal studies after bacterial challenge post immunisation in mice have shown bacterial clearance. The antiserum from mice showed binding and clearance of the Klebsiella pneumoniae bacteria in vitro and in vivo. These antigens used for generating an active immune response in mice can further be used for therapeutic monoclonal antibody development against Klebsiella pneumoniae infections.

Keywords: antiserum, FepA, Klebsiella pneumoniae, multi drug resistance, siderophore receptor

Procedia PDF Downloads 98
301 Multilayered Assembly of Gelatin on Nanofibrous Matrix for 3-D Cell Cultivation

Authors: Ji Un Shin, Wei Mao, Hyuk Sang Yoo

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Electrospinning is a versatile tool for fabricating nano-structured polymeric materials. Gelatin hydrogels are considered to be a good material for cell cultivation because of high water swellability as well as good biocompatibility. Three-dimensional (3-D) cell cultivation is a desirable method of cell cultivation for preparing tissues and organs because cell-to-cell interactions or cell-to-matrix interactions can be much enhanced through this approach. For this reason, hydrogels were widely employed as tissue scaffolds because they can support cultivating cells and tissue in multi-dimensions. Major disadvantages of hydrogel-based cell cultivation include low mechanical properties, lack of topography, which should be enhanced for successful tissue engineering. Herein we surface-immobilized gelatin on the surface of nanofibrous matrix for 3-D cell cultivation in topographical cues added environments. Electrospun nanofibers were electrospun with injection of poly(caprolactone) through a single nozzle syringe. Electrospun meshes were then chopped up with a high speed grinder to fine powders. This was hydrolyzed in optimized concentration of sodium hydroxide solution from 1 to 6 hours and harvested by centrifugation. The freeze-dried powders were examined by scanning electron microscopy (SEM) for revealing the morphology and fibrilar shaped with a length of ca. 20um was observed. This was subsequently immersed in gelatin solution for surface-coating of gelatin, where the process repeated up to 10 times for obtaining desirable coating of gelatin on the surface. Gelatin-coated nanofibrils showed high waterswellability in comparison to the unmodified nanofibrils, and this enabled good dispersion properties of the modified nanofibrils in aqueous phase. The degree of water-swellability was increased as the coating numbers of gelatin increased, however, it did not any meaning result after 10 times of gelatin coating process. Thus, by adjusting the gelatin coating times, we could successfully control the degree of hydrophilicity and water-swellability of nanofibrils.

Keywords: nano, fiber, cell, tissue

Procedia PDF Downloads 164
300 Targeted Delivery of Sustained Release Polymeric Nanoparticles for Cancer Therapy

Authors: Jamboor K. Vishwanatha

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Among the potent anti-cancer agents, curcumin has been found to be very efficacious against various cancer cells. Despite multiple medicinal benefits of curcumin, poor water solubility, poor physiochemical properties and low bioavailability continue to pose major challenges in developing a formulation for clinical efficacy. To improve its potential application in the clinical area, we formulated poly lactic-co-glycolic acid (PLGA) nanoparticles. The PLGA nanoparticles were formulated using solid-oil/water emulsion solvent evaporation method and then characterized for percent yield, encapsulation efficiency, surface morphology, particle size, drug distribution within nanoparticles and drug polymer interaction. Our studies showed the successful formation of smooth and spherical curcumin loaded PLGA nanoparticles with a high percent yield of about 92.01±0.13% and an encapsulation efficiency of 90.88±0.14%. The mean particle size of the nanoparticles was found to be 145nm. The in vitro drug release profile showed 55-60% drug release from the nanoparticles over a period of 24 hours with continued sustained release over a period of 8 days. Exposure to curcumin loaded nanoparticles resulted in reduced cell viability of cancer cells compared to normal cells. We used a novel non-covalent insertion of a homo-bifunctional spacer for targeted delivery of curcumin to various cancer cells. Functionalized nanoparticles for antibody/targeting agent conjugation was prepared using a cross-linking ligand, bis(sulfosuccinimidyl) suberate (BS3), which has reactive carboxyl group to conjugate efficiently to the primary amino groups of the targeting agents. In our studies, we demonstrated successful conjugation of antibodies, Annexin A2 or prostate specific membrane antigen (PSMA), to curcumin loaded PLGA nanoparticles for targeting to prostate and breast cancer cells. The percent antibody attachment to PLGA nanoparticles was found to be 92.8%. Efficient intra-cellular uptake of the targeted nanoparticles was observed in the cancer cells. These results have emphasized the potential of our multifunctional curcumin nanoparticles to improve the clinical efficacy of curcumin therapy in patients with cancer.

Keywords: polymeric nanoparticles, cancer therapy, sustained release, curcumin

Procedia PDF Downloads 323
299 Comparative Study of Antimicrobial, Antioxidant and Physicochemical Properties of Four Culinary Herbs Grown in Sri Lanka

Authors: Thilini Kananke

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Culinary herbs have long been considered as significant dietary sources of many potential health-promoting compounds. The present research focused on analysis of antimicrobial, antioxidant and physicochemical properties in selected four culinary herbs namely Murraya koenigii (Curry leaves), Pandanus amaryllifolius (Pandan leaves), Cymbopogon citrates (Lemon grass leaves), and Mentha Piperita (Minchi leaves) obtained from several market sites in Ratnapura District, Sri Lanka. The antimicrobial activity of ethanolic, chloroform and distilled water extracts of culinary herbs were evaluated against the strains of Staphylococcus aureus, Salmonella typhi and Shigella spp. Total phenolic content and the radical scavenging activity (using DPPH assay) of culinary herbs were determined. Four heavy metals (Cu, Cd, Pb and Fe) were analyzed in the selected culinary herbs using the atomic absorption spectroscopy (AAS). Proximate compositions of the selected herbs were analyzed using AOAC official methods. Antimicrobial activity of all selected culinary herbs showed relativity high inhibition zones against S. aureus. Pandan leaves showed the least antimicrobial activity against selected bacterial strains compared with other culinary herbs. Both the highest radical scavenging activity (lower IC50 value) and the total phenolic content (25.57 ±3.54µg GAE/100g) were reported in Mentha piperita extract. The highest concentrations of Cu, Fe and Cd were reported in Curry leaves (29.15 mg/kg), Lemon grass leaves (257.98 mg/kg) and Pandan leaves (6.05 mg/kg) respectively. The heavy metal contents detected in all culinary herbs were below the permitted limits set by WHO/FAO, except Cd. The highest moisture (85.00±0.00%) and fiber (10.66± 2.00%) contents were found in Pandan leaves, while the highest protein (8.94±0.29%), fat (12.3± 2.52%) and ash (3.50± 0.17%) contents were reported in curry leaves. The information obtained from this study highlights the importance of further investigation of other antioxidant, antimicrobial and health promoting compounds of culinary herbs available in Sri Lanka for a detailed comparison.

Keywords: antimicrobial, antioxidant, culinary herbs, proximate analysis

Procedia PDF Downloads 169