Search results for: yeast to hyphae conversion inhibition
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2492

Search results for: yeast to hyphae conversion inhibition

2252 Enhancing Inhibition on Phytopathogens by Complex Using Biogas Slurry

Authors: Fang-Bo Yu, Li-Bo Guan, Sheng-Dao Shan

Abstract:

Biogas slurry was mixed with six commercial fungicides and screening against 11 phytopathogens was carried out. Results showed that inhibition of biogas slurry was different for the test strains and no significant difference between treatments of Didymella bryoniae, Fusarium oxysporum f. sp. vasinfectum, Aspergillus niger, Rhizoctonia cerealis, F. graminearum and Septoria tritici was observed. However, significant differences were found among Penicillium sp., Botrytis cinerea, Alternaria sonali, F. oxysporum F. sp. melonis and Sclerotinia sclerotiorum. The approach described here presents a promising alternative to current manipulation although some issues still need further examination. This study could contribute to the development of sustainable agriculture and better utilization of biogas slurry.

Keywords: anaerobic digestion, biogas slurry, phytopathogen, sustainable agriculture

Procedia PDF Downloads 333
2251 Rapid Mitochondrial Reactive Oxygen Species Production Precedes NF-κB Activation and Pro-inflammatory Responses in Macrophages

Authors: Parinaz Tavakoli Zaniani, Dimitrios Balomenos

Abstract:

Mitochondrial reactive oxygen species (mROS) play a crucial role in macrophage pro-inflammatory activation, although a detailed understanding of the mechanism and kinetics by which mROS drive signaling molecules is still lacking. In general, it is thought that NF-κB activation drives mROS and general ROS production. Here, We performed a detailed kinetic analysis of mROS production during macrophage activation. We found early mROS generation after LPS (lipopolysaccharide) stimulation. Remarkably as early as 5 minutes, mROS signaling promoted initial NF-κB, MAPK activation and pro-inflammatory cytokine production, as established through inhibition or quenching of mROS. On the contrary, NF-κB inhibition had no effect on mROS production. Our findings point to a mechanism by which mROS increase TRAF-6 ubiquitination and, thus NF-κB activity. mROS inhibition reduced LPS-induced lethality in an in vivo septic shock model by controlling pro-inflammatory cytokine production. Overall, our research provides novel insights into the role of mROS as a primary messenger in the pathway of macrophage and as a regulator of inflammatory responses. We found that early mROS production promotes initial NF-κB, and MAPK activation by regulating TRAF-6 ubiquitination and that mROS inhibition can reduce LPS-induced inflammatory cytokines and lethality in a septic shock model. These findings might lead to novel immunotherapeutic strategies targeting early mROS production and control of extreme inflammation in the context of sepsis and other inflammatory diseases.

Keywords: mitochondria, reactive oxygen species, nuclear factor κB, lipopolysaccharide, macrophages

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2250 Combined Treatment of PARP-1 Inhibitor and Carbon Ion or Gamma Exposure Reduces the Metastatic Potential in Cultured Human Cells

Authors: Priyanka Chowdhury, Asitikantha Sarma, Utpal Ghosh

Abstract:

Hadron therapy using high Linear Energy Transfer (LET) ion beam is producing promising clinical results worldwide. The major advantages are its ability to kill radio-resistant tumor and its anti-metastatic activity. Poly(ADP-ribose) polymerase-1 (PARP-1) inhibitors have been widely used as radiosensitizer, but its role in metastasis is unknown. The purpose of our study was to investigate the effect of PARP-1 depletion in combination with either Carbon Ion Beam (CIB) or gamma irradiation on metastatic potential of cultured cancerous cells. A549 cells were irradiated with CIB (0-4Gy) or gamma (0, 2, 4, 6 and 10 Gy) with and without PARP-1 inhibition. The metastatic potential of the cells was determined by cell migratory assay, expression, and activity of MMP-2 and MMP-9, expression of Cadherin, Fibronectin, and Vimentin. CIB exposure reduced migratory property and activity of MMP-2 and MMP-9 significantly. CIB with PARP-1 inhibition reduced cell migration and Matrix Metalloproteinase (MMPs) activity in a synergistic manner. Expression of MMPs was also down-regulated in CIB and combined treatment. On the contrary, MMP- 2 and MMP-9 activity was significantly increased in gamma irradiated cells but decreased upon combined treatment of gamma and PARP-1 inhibitor. MMPs expression and migration was reduced when gamma irradiation was combined with PARP-1 inhibition. Thus, our study clearly demonstrates that PARP-1 inhibition in combination with either high or low LET can significantly suppress metastatic potential in cancer cells and thereby can be a promising tool in controlling metastatic cancers.

Keywords: high LET, low LET, matrix metalloproteinase (MMP), PARP-1

Procedia PDF Downloads 214
2249 Biocontrol Potential of Growth Promoting Rhizobacteria against Root Rot of Chili and Enhancement of Plant Growth

Authors: Kiran Nawaz, Waheed Anwar, Sehrish Iftikhar, Muhammad Nasir Subhani, Ahmad Ali Shahid

Abstract:

Plant growth promoting rhizobacteria (PGPR) have been extensively studied and applied for the biocontrol of many soilborne diseases. These rhizobacteria are very efficient against root rot and many other foliar diseases associated with solanaceous plants. These bacteria may inhibit the growth of various pathogens through direct inhibition of target pathogens or indirectly by the initiation of systemic resistance (ISR) which is active all over the complete plant. In the present study, 20 different rhizobacterial isolates were recovered from the root zone of healthy chili plants. All soil samples were collected from various chili-growing areas in Punjab. All isolated rhizobacteria species were evaluated in vitro and in vivo against Phytophthora capsici. Different species of Bacillus and Pseudomonas were tested for the antifungal activity against P. capsici the causal organism of Root rot disease in different crops together with chili. Dual culture and distance culture bioassay were carried out to study the antifungal potential of volatile and diffusible metabolites secreted from rhizobacteria. After seven days of incubation at 22°C, growth inhibition rate was recorded. Growth inhibition rate depended greatly on the tested bacteria and screening methods used. For diffusible metabolites, inhibition rate was 35-62% and 20-45% for volatile metabolites. The screening assay for plant growth promoting and disease inhibition potential of chili associated PGPR indicated 42-100% reduction in disease severity and considerable enhancement in roots fresh weight by 55-87%, aerial parts fresh weight by 35-65% and plant height by 65-76% as compared to untreated control and pathogen-inoculated plants. Pseudomonas flourescene, B. thuringiensis, and B. subtilis were found to be the most efficient isolates in inhibiting P. capsici radial growth, increase plant growth and suppress disease severity.

Keywords: rhizobacteria, chili, phytophthora, root rot

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2248 The Effect of a Muscarinic Antagonist on the Lipase Activity

Authors: Zohreh Bayat, Dariush Minai-Tehrani

Abstract:

Lipases constitute one of the most important groups of industrial enzymes that catalyze the hydrolysis of triacylglycerol to glycerol and fatty acids. Muscarinic antagonist relieves smooth muscle spasm of the gastrointestinal tract and effect on the cardiovascular system. In this research, the effect of a muscarinic antagonist on the lipase activity of Pseudomonas aeruginosa was studied. Lineweaver–Burk plot showed that the drug inhibited the enzyme by competitive inhibition. The IC50 value (60 uM) and Ki (30 uM) of the drug revealed the drug bound to the enzyme with high affinity. Determination of enzyme activity in various pH and temperature showed that the maximum activity of lipase was at pH 8 and 60°C both in presence and absence of the drug.

Keywords: bacteria, inhibition, kinetics, lipase

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2247 Therapeutical Role of Copper Oxide Nanoparticles (CuO NPs) for Breast Cancer Therapy

Authors: Dipranjan Laha, Parimal Karmakar

Abstract:

Metal oxide nanoparticles are well known to generate oxidative stress and deregulate normal cellular activities. Among these, transition metals copper oxide nanoparticles (CuO NPs) are more compelling than others and able to modulate different cellular responses. In this work, we have synthesized and characterized CuO NPs by various biophysical methods. These CuO NPs (~30 nm) induce autophagy in human breast cancer cell line, MCF7 in a time and dose-dependent manner. Cellular autophagy was tested by MDC staining, induction of green fluorescent protein light chain 3 (GFP-LC3B) foci by confocal microscopy, transfection of pBABE-puro mCherry-EGFP-LC3B plasmid and western blotting of autophagy marker proteins LC3B, beclin1, and ATG5. Further, inhibition of autophagy by 3-Methyladenine (3-MA) decreased LD50 doses of CuO NPs. Such cell death was associated with the induction of apoptosis as revealed by FACS analysis, cleavage of PARP, dephosphorylation of Bad and increased cleavage product of caspase3. siRNA-mediated inhibition of autophagy-related gene beclin1 also demonstrated similar results. Finally, induction of apoptosis by 3-MA in CuO NPs treated cells were observed by TEM. This study indicates that CuO NPs are a potent inducer of autophagy which may be a cellular defense against the CuO NPs mediated toxicity and inhibition of autophagy switches the cellular response into apoptosis. A combination of CuO NPs with the autophagy inhibitor is essential to induce apoptosis in breast cancer cells. Acknowledgments: The authors would like to acknowledge for financial support for this research work to the Department of Biotechnology (No. BT/PR14661/NNT/28/494/2010), Government of India.

Keywords: nanoparticle, autophagy, apoptosis, siRNA-mediated inhibition

Procedia PDF Downloads 440
2246 Theoretical Study of Carbonic Anhydrase-Ii Inhibitors for Treatment of Glaucoma

Authors: F. Boukli Hacene, W. Soufi, S. Ghalem

Abstract:

Glaucoma disease is a progressive degenerative optic neuropathy, with irreversible visual field deficits and high eye pressure being one of the risk factors. Sulfonamides are carbonic anhydrase-II inhibitors that aim to decrease the secretion of aqueous humor by direct inhibition of this enzyme at the level of the ciliary processes. These drugs present undesirable effects that are difficult to accept by the patient. In our study, we are interested in the inhibition of carbonic anhydrase-II by different natural ligands (curcumin analogues) using molecular modeling methods using molecular operating environment (MOE) software to predict their interaction with this enzyme.

Keywords: carbonic anhydrase-II, curcumin analogues, drug research, molecular modeling

Procedia PDF Downloads 89
2245 Avoiding Gas Hydrate Problems in Qatar Oil and Gas Industry: Environmentally Friendly Solvents for Gas Hydrate Inhibition

Authors: Nabila Mohamed, Santiago Aparicio, Bahman Tohidi, Mert Atilhan

Abstract:

Qatar's one of the biggest problem in processing its natural resource, which is natural gas, is the often occurring blockage in the pipelines caused due to uncontrolled gas hydrate formation in the pipelines. Several millions of dollars are being spent at the process site to dehydrate the blockage safely by using chemical inhibitors. We aim to establish national database, which addresses the physical conditions that promotes Qatari natural gas to form gas hydrates in the pipelines. Moreover, we aim to design and test novel hydrate inhibitors that are suitable for Qatari natural gas and its processing facilities. From these perspectives we are aiming to provide more effective and sustainable reservoir utilization and processing of Qatari natural gas. In this work, we present the initial findings of a QNRF funded project, which deals with the natural gas hydrate formation characteristics of Qatari type gas in both experimental (PVTx) and computational (molecular simulations) methods. We present the data from the two fully automated apparatus: a gas hydrate autoclave and a rocking cell. Hydrate equilibrium curves including growth/dissociation conditions for multi-component systems for several gas mixtures that represent Qatari type natural gas with and without the presence of well known kinetic and thermodynamic hydrate inhibitors. Ionic liquids were designed and used for testing their inhibition performance and their DFT and molecular modeling simulation results were also obtained and compared with the experimental results. Results showed significant performance of ionic liquids with up to 0.5 % in volume with up to 2 to 4 0C inhibition at high pressures.

Keywords: gas hydrates, natural gas, ionic liquids, inhibition, thermodynamic inhibitors, kinetic inhibitors

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2244 Phytochemical Study and Antimicrobial Activity of Nigella sativa L. (Renunculaceae) in Algeria

Authors: L. Bendifallah, F. Acheuk, M. Djouabi, M. Oukili, R. Ghezraoui, W. Lakhdari, R. Allouane

Abstract:

Nigella sativa L. (Renunculaceae) native to the Mediterranean region and Western Asia, Black cumin is grown to India, through Sudan and Ethiopia. It is widely cultivated in Egypt, the Middle East, Saudi Arabia, Turkey, Sudan, Afghanistan and Europe. It is among the most important medicinal plants in Algeria that is known for its antifungal and antimicrobial properties. Despite its plethora of uses for treating various diseases, it has garnered very little scientific interest so far, particularly in Algeria. For this study, the seeds of Algerian Nigella sativa L cultivated in the area of Magra (M’sila) in northern Algeria, were collected in summer. In such a propitious context, the aim of this study was to enhance Nigella sativa as a medicinal herb. The phytochemical screening methods are used. For their antimicrobial activity, extracts of tannin and polyphenols were screened against four pathogenic bacterial strains and two pathogenic yeast strains. The phytochemical analysis results showed a remarkable combination of chemical components including a high content in tannins, in flavonoïds, and in alkaloids. The tannins and the polyphenols have strong antimicrobial activity against all the species. The maximum zone of inhibition was noted for polyphenol and tannin extracts against Escerichia coli (14 mm, 12.33 mm) and an antifungic activity against Aspergillus niger (11.66 mm, 9 mm). These results indicate to some benefits of Nigella sativa seeds which can use to treatment the microbial infection.

Keywords: Nigella sativa, phytochemistry, antimicrobial activity, Algeria

Procedia PDF Downloads 324
2243 Phytochemical Study and Antimicrobial Activity of Nigella Sativa L. (Renunculaceae) in Algeria

Authors: L. Bendifallah, F.Acheuk, M. Djouabi, M. Oukili, R. Ghezraoui, W. Lakhdari, R. Allouane

Abstract:

Nigella sativa L. (Renunculaceae) native to the Mediterranean region and Western Asia, Black cumin is grown to India, through Sudan and Ethiopia. It is widely cultivated in Egypt, the Middle East, Saudi Arabia, Turkey, Sudan, Afghanistan and Europe. It is among the most important medicinal plants in Algeria that is known for its antifungal and antimicrobial properties. Despite its plethora of uses for treating various diseases, it has garnered very little scientific interest so far, particularly in Algeria. For this study, the seeds of Algerian Nigella sativa L cultivated in the area of Magra (M’sila) in northern Algeria, were collected in summer. In such a propitious context, the aim of this study was to enhance Nigella sativa as a medicinal herb. The phytochemical screening methods are used. For their antimicrobial activity, extracts of tannin and polyphenols were screened against four pathogenic bacterial strains and two pathogenic yeast strains. The phytochemical analysis results showed a remarkable combination of chemical components including a high content in tannins, in flavonoïds, and in alkaloids. The tannins and the polyphenols have strong antimicrobial activity against all the species. The maximum zone of inhibition was noted for polyphenol and tannin extracts against Escerichia coli (14 mm, 12.33 mm) and an antifungic activity against Aspergillus niger (11.66 mm, 9 mm). These results indicate to some benefits of Nigella sativa seeds which can use to treatment the microbial infection.

Keywords: Algeria, antimicrobial activity, Nigella sativa, phytochemistry

Procedia PDF Downloads 564
2242 A New Converter Topology for Wind Energy Conversion System

Authors: Mahmoud Khamaira, Ahmed Abu-Siada, Yasser Alharbi

Abstract:

Doubly Fed Induction Generators (DFIGs) are currently extensively used in variable speed wind power plants due to their superior advantages that include reduced converter rating, low cost, reduced losses, easy implementation of power factor correction schemes, variable speed operation and four quadrants active and reactive power control capabilities. On the other hand, DFIG sensitivity to grid disturbances, especially for voltage sags represents the main disadvantage of the equipment. In this paper, a coil is proposed to be integrated within the DFIG converters to improve the overall performance of a DFIG-based wind energy conversion system (WECS). The charging and discharging of the coil are controlled by controlling the duty cycle of the switches of the dc-dc chopper. Simulation results reveal the effectiveness of the proposed topology in improving the overall performance of the WECS system under study.

Keywords: doubly fed induction generator, coil, wind energy conversion system, converter topology

Procedia PDF Downloads 661
2241 Inhibiting Effects of Zwitterionic Surfactant on the Erosion-Corrosion of API X52 Steel in Oil Sands Slurry

Authors: M. A. Deyab

Abstract:

The effect of zwitterionic surfactant (ZS) on erosion-corrosion of API X52 steel in oil sands slurry was studied using Tafel polarization and anodic polarization measurements. The surface morphology of API X52 steel was examined with scanning electron microscopy (SEM) and atomic force microscopy (AFM). ZS inhibited the erosion-corrosion of API X52 steel in oil sands' slurry, and the inhibition efficiency increased with increasing ZS concentration but decreased with increasing temperature. Polarization curves indicate that ZS act as a mixed type of inhibitor. Inhibition efficiencies of ZS in the dynamic condition are not as effective as that obtained in the static condition.

Keywords: corrosion, surfactant, oil sands slurry, erosion-corrosion

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2240 Determination of the Oxidative Potential of Organic Materials: Method Development

Authors: Jui Afrin, Akhtarul Islam

Abstract:

In this paper, the solution of glucose, yeast and glucose yeast mixture are being used as sample solution for determining the chemical oxygen demand (COD). In general COD determination method used to determine the different rang of oxidative potential. But in this work has shown to determine the definite oxidative potential for different concentration for known COD value and wanted to see the difference between experimental value and the theoretical value for evaluating the method drawbacks. In this study, made the values of oxidative potential like 400 mg/L, 500 mg/L, 600 mg/L, 700 mg/L and 800mg/L for various sample solutions and determined the oxidative potential according to our developed method. Plotting the experimental COD values vs. sample solutions of various concentrations in mg/L to draw the curve. From these curves see that the curves for glucose solution is not linear; its deviate from linearity for the lower concentration and the reason for this deviation is unknown. If these drawback can be removed this method can be effectively used to determine Oxidative Potential of Industrial wastewater (such as: Leather industry wastewater, Municipal wastewater, Food industry wastewater, Textile wastewater, Pharmaceuticals waste water) that’s why more experiment and study required.

Keywords: bod (biological oxygen demand), cod (chemical oxygen demand), oxidative potential, titration, waste water, development

Procedia PDF Downloads 229
2239 Maximum Power Point Tracking Based on Estimated Power for PV Energy Conversion System

Authors: Zainab Almukhtar, Adel Merabet

Abstract:

In this paper, a method for maximum power point tracking of a photovoltaic energy conversion system is presented. This method is based on using the difference between the power from the solar panel and an estimated power value to control the DC-DC converter of the photovoltaic system. The difference is continuously compared with a preset error permitted value. If the power difference is more than the error, the estimated power is multiplied by a factor and the operation is repeated until the difference is less or equal to the threshold error. The difference in power will be used to trigger a DC-DC boost converter in order to raise the voltage to where the maximum power point is achieved. The proposed method was experimentally verified through a PV energy conversion system driven by the OPAL-RT real time controller. The method was tested on varying radiation conditions and load requirements, and the Photovoltaic Panel was operated at its maximum power in different conditions of irradiation.

Keywords: control system, error, solar panel, MPPT tracking

Procedia PDF Downloads 283
2238 Optimization of Heterojunction Solar Cell Using AMPS-1D

Authors: Benmoussa Dennai, H. Benslimane, A. Helmaoui

Abstract:

Photo voltaic conversion is the direct conversion of electromagnetic energy into electrical energy continuously. This electromagnetic energy is the most solar radiation. In this work we performed a computer modelling using AMPS 1D optimization of hetero-junction solar cells GaInP/GaAs configuration for p/ n. We studied the influence of the thickness the base layer in the cell offers on the open circuit voltage, the short circuit current and efficiency.

Keywords: optimization, photovoltaic cell, GaInP / GaAs AMPS-1D, hetetro-junction

Procedia PDF Downloads 417
2237 Cognitive Behavior Therapy with a Migrant Pakistani in Malaysia: A Single Case Study of Conversion Disorder

Authors: Fahad R. Choudhry., Khadeeja Munawar

Abstract:

This clinical case presents a 24 years old, Muslim Pakistani girl with a history of conversion disorder. Her symptoms comprised fits, restlessness, numbness in legs, poor coordination and balance, burning during urination and retention. A cognitive-behavioral model was used for conceptualizing her problem and devising a management plan based on cognitive behavioral therapy (CBT) and culturally adapted coping statements. She took 13 therapy sessions and was presented with idiosyncratic case conceptualization. Psychoeducation, coping statements, extinction, verbal challenging, and behavioral activation techniques were practiced in a collaborative way for cognitive restructuring of the client. Focus of terminal sessions was on anger management. The client needed a couple of more sessions in order to help her manage her anger. However, the therapy was terminated on the part of the client after attainment of short term goals. The client reported to have a 75 % improvement in her overall condition and remained compliant throughout the therapy.

Keywords: cognitive behavioral therapy, conversion disorder, female, Muslim, Pakistani

Procedia PDF Downloads 194
2236 Study of Inhibition of the End Effect Based on AR Model Predict of Combined Data Extension and Window Function

Authors: Pan Hongxia, Wang Zhenhua

Abstract:

In this paper, the EMD decomposition in the process of endpoint effect adopted data based on AR model to predict the continuation and window function method of combining the two effective inhibition. Proven by simulation of the simulation signal obtained the ideal effect, then, apply this method to the gearbox test data is also achieved good effect in the process, for the analysis of the subsequent data processing to improve the calculation accuracy. In the end, under various working conditions for the gearbox fault diagnosis laid a good foundation.

Keywords: gearbox, fault diagnosis, ar model, end effect

Procedia PDF Downloads 366
2235 Comparison of Filamentous Fungus (Monascus purpureus)Growth in Submerged and Solid State Culture

Authors: Shafieeh Mansoori, Fatemeh Yazdian, Ashrafsadat Hatamian, Majid Azizi

Abstract:

Monascus purpureus, which has a special metabolite with many therapeutic and medicinal properties including antioxidant, antibiotic, anti-hypercholesterolemia, and immunosuppressive properties, is a traditional Chinese fermentation fungus and is used as a natural dietary supplement. Production of desired metabolites actually determined by optimized growth which is supported by some factors such as substrates and Monascus strains type, moisture content of the fermentation mixture, aeration, and control of contamination issues. In this experiment, M. purpureus PTCC5305 was cultured in both the liquid and solid culture medium. The former medium contain YMP (yeast extract, maltose and peptone), PGC (peptone, glucose complex), and GYP (glucose, yeast extract and peptone) medium. After 8 days, the best medium for the cell production was PGC agar medium on solid culture with 0.28 g dry weight of cell mass whereas the best liquid culture was GYP medium with 3.5 g/l dry weight of cell mass. The lowest cell production was on YMP agar with 0.1 g dry weight of cell mass and then YMP medium with 2.5 g/l dry cell weight.

Keywords: Monascus purpureus, solid state fermentation, submerged culture, Chinese fermentation fungus

Procedia PDF Downloads 407
2234 Optimization of Heterojunction Solar Cell Using AMPS-1D

Authors: Benmoussa Dennai, H. Benslimane, A. Helmaoui

Abstract:

Photovoltaic conversion is the direct conversion of electromagnetic energy into electrical energy continuously. This electromagnetic energy is the most solar radiation. In this work we performed a computer modelling using AMPS 1D optimization of hetero-junction solar cells GaInP / GaAs configuration for p / n. We studied the influence of the thickness the base layer in the cell offers on the open circuit voltage, the short circuit current and efficiency.

Keywords: optimization, photovoltaic cell, GaInP / GaAs AMPS-1D, hetetro-junction

Procedia PDF Downloads 518
2233 The Influence of Thomson Effect on the Performance of N-Type Skutterudite Thermoelement

Authors: Anbang Liu, Huaqing Xie, Zihua Wu, Xiaoxiao Yu, Yuanyuan Wang

Abstract:

Due to the temperature-dependence and mutual coupling of thermoelectric parameters, the Thomson effect always exists, which is derived from temperature gradients during thermoelectric conversion. The synergistic effect between the Thomson effect and non-equilibrium heat transport of charge carriers leads to local heat absorption or release in thermoelements, thereby affecting its power generation performance and conversion efficiency. This study verified and analyzed the influence and mechanism of the Thomson effect on N-type skutterudite thermoelement through quasi-steady state testing under approximate vacuum conditions. The results indicate the temperature rise/fall of N-type thermoelement at any position is affected by Thomson heat release/absorption. Correspondingly, the Thomson effect also contributes advantageously/disadvantageously to the output power of N-type skutterudite thermoelement when the Thomson coefficients are positive/negative. In this work, the output power can be promoted or decreased maximally by more than 27% due to the presence of Thomson heat when the absolute value of the Thomson coefficient is around 36 μV/℃.

Keywords: Thomson effect, heat transport, thermoelectric conversion, numerical simulation

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2232 Modeling of Nanocomposite Films Made of Cloisite 30b- Metal Nanoparticle in Packaging of Soy Burger

Authors: Faranak Beigmohammadi, Seyed Hadi Peighambardoust, Seyed Jamaledin Peighambardoust

Abstract:

This study undertakes to investigate the ability of different kinds of nanocomposite films made of cloisite-30B with different percentages of silver and copper oxide nanoparticles incorporated into a low-density polyethylene (LDPE) polymeric matrix by a melt mixing method in order to inhibit the growth of microorganism in soy burger. The number of surviving cell of the total count was decreased by 3.61 log and mold and yeast diminished by 2.01 log after 8 weeks storage at 18 ± 0.5°C below zero, whilst pure LDPE did not has any antimicrobial effect. A composition of 1.3 % cloisite 30B-Ag and 2.7 % cloisite 30B-CuO for total count and 0 % cloisite 30B-Ag and 4 % cloisite 30B-CuO for yeast & mold gave optimum points in combined design test in Design Expert 7.1.5. Suitable microbial models were suggested for retarding above microorganisms growth in soy burger. To validation of optimum point, the difference between the optimum point of nanocomposite film and its repeat was not significant (p<0.05) by one-way ANOVA analysis using SPSS 17.0 software, while the difference was significant for pure film. Migration of metallic nanoparticles into a food stimulant was within the accepted safe level.

Keywords: modeling, nanocomposite film, packaging, soy burger

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2231 Enzyme Inhibition Activity of Schiff Bases Against Mycobacterium Tuberculosis Using Molecular Docking

Authors: Imran Muhammad

Abstract:

The main cause of infectious disease in the modern world is Mycobacterium Tuberculosis (MT). To combat tuberculosis, new and efficient drugs are an urgent need in the modern world. Schif bases are potent for their biological pharmacophore activity. Thus we selected different Vanillin-based Schiff bases for their binding activity against target enzymes of Mycobacterium tuberculosis that is (DprE1 (decaprenyl phosphoryl-β-D-ribose 2′-epimerase), and DNA gyrase subunit-A), using molecular docking. We evaluate the inhibition potential, interaction, and binding mode of these compounds with the target enzymes.

Keywords: schiff bases, tuberculosis, DNA gyrase, DprE1, docking

Procedia PDF Downloads 75
2230 Formulation and Evaluation of Antioxidant Cream Containing Nepalese Medicinal Plants

Authors: Ajaya Acharya, Prem Narayan Paudel, Rajendra Gyawali

Abstract:

Due to strong tyrosinase inhibition and antioxidant effects, green tea and Licorice are valuable in cosmetics for the skin. However, data on the addition of essential oils to green tea and Licorice in cream formulation to examine antioxidant activities are limited. The purpose of this study was to develop and assess a phytocosmetic cream’s antioxidant and tyrosinase inhibitory characteristics using crude aqueous extracts of green tea, Licorice, and loaded with essential oils. To load the best concentration on cream formulations, plant aqueous extracts were designed, evaluated, and correlated in terms of total phenolic content (TPC), total flavonoids content (TFC), and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity. Moreover, o. tenuiflorum and o. basilicum essential oils were extracted and added to a cream formulation. The spreadability profile, water washability, centrifugation test, and organoleptic characteristics of formulated oil in water cream were all satisfactory. The cream exhibited a non-Newtonian rheological profile and pH range of 6.353 ± 0.065 to 6.467±0.050 over successive 0, 1, 2, and 3 months at normal room temperature. The 50% inhibition concentrations shown by herbal cream were 13.764 ± 0.153 µg/ml, 301.445 ± 1.709 µg/ml and 8.082 ± 0.055 respectively for 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, ferric (Fe³⁺) reducing antioxidant power (FRAP) and 2, 2’-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, and that of standard ascorbic acid were 6.716 ± 0.077 µg/ml, 171.604 ± 1.551µg/ml and 5.645±0.034µg/ml which showed formulated cream had strong antioxidant characteristics. The formulated herbal cream with a 50% tyrosinase inhibition concentration of 22.254 ± 0.369µg/ml compared to standard Kojic acid 12.535 ± 0.098µg/ml demonstrated a satisfactory tyrosinase inhibition profile for skin whitening property. Herbal cream was reportedly stable in physical and chemical parameters for successive 0, 1, 2, and 3 months at both real and accelerated time study zones, according to obtained stability study results.

Keywords: crude extracts, antioxidant, tyrosinase inhibition, green tea polyphenols

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2229 Rare-Earth Ions Doped Zirconium Oxide Layers for Optical and Photovoltaic Applications

Authors: Sylwia Gieraltowska, Lukasz Wachnicki, Bartlomiej S. Witkowski, Marek Godlewski

Abstract:

Oxide layers doped with rare-earth (RE) ions in optimized way can absorb short (ultraviolet light), which will be converted to visible light by so-called down-conversion. Down-conversion mechanisms are usually exploited to modify the incident solar spectrum. In down conversion, multiple low-energy photons are generated to exploit the energy of one incident high-energy photon. These RE-doped oxide materials have attracted a great deal of attention from researchers because of their potential for optical manipulation in optical devices (detectors, temperature sensors, and compact solid-state lasers, light-emitting diodes), bio-analysis, medical therapy, display technologies, and light harvesting (such as in photovoltaic cells). The zirconium dioxide (ZrO2) doped RE ions (Eu, Tb, Ce) multilayer structures were tested as active layers, which can convert short wave emission to light in the visible range (the down-conversion mechanism). For these applications original approach of deposition ZrO2 layers using the Atomic Layer Deposition (ALD) method and doping these layers with RE ions using the spin-coating technique was used. ALD films are deposited at relatively low temperature (well below 250°C). This can be an effective method to achieve the white-light emission and to improve on this way light conversion efficiency, by an extension of absorbed spectral range by a solar cell material. Photoluminescence (PL), X-ray diffraction (XRD), scanning electron microscope (SEM) and atomic force microscope (AFM) measurement are analyzed. The research was financially supported by the National Science Centre (decision No. DEC-2012/06/A/ST7/00398 and DEC- 2013/09/N/ST5/00901).

Keywords: ALD, oxide layers, photovoltaics, thin films

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2228 In vitro Control of Mycosphaerella arachidis Deighton the Early Leaf Spot Disease Pathogen of Groundnut by the Extracts from Six Medicinal Plants

Authors: Matthew Omoniyi Adebola, Jude E Amadi

Abstract:

Ground nut (Arachis hypogaea) is one of the most popular commercial crops in Nigeria. Its suc-cessful production has been drastically affected by early leaf spot disease caused by Mycosphae-rella arachidis Deighton. In vitro control of the pathogen by six medicinal plants (Entada afri-cana, Vitex doniana, Lawsonia inermis, Azadirachta indica, Acalypha hispida and Nuaclea lati-folia) was assessed in this study. The extracts of the plants were prepared using cold and hot wa-ter and alcohol. The pathogen was isolated from ground nut infected with early leaf spot disease. The results revealed a great significant difference (P<0.05) in yield of extracts between cold water, hot water, and alcohol extracts. A significant difference (P<0.05) was observed in percentage concentrations of the various phytochemical constituents present in the extracts. Flavonoids per-centage concentration was the highest (0.68 - 1.95%) followed by saponnin(0.09-1.53%) in N. latifolia extracts. Steroiods had the least percentage concentrations (0.00- 0.09%)followed by terpenoids(0.02–0.71%) and proanthocyannin (0.05 – 0.86%). N. latifolia extracts produced the highest percentage concentrations (0.07–1.95%) of all the phytochemicals followed by A. indi-ca(0.05–1.64%)and least concentrations were obtained in A. hispidia(0.09 – 0.87%)and V. do-niana (0.00–0.88%). The extracts inhibited spore germination and growth of M. arachidis. The inhibition by alcohol extracts was high and significantly different (P>0.05) from cold and hot water extracts. Alcohol extract of L. inermis gave 100% spore germination inhibition followed by N. latifolia and A.indica with 97.75% and 85.60% inhibition respectively. Therefore, field trials of these six medicinal plants on the control of early leaf spot disease of ground nut are rec-ommended.

Keywords: groundnut, phytochemicals, medicinal plants, extracts, inhibition

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2227 Electrochemical and Theoretical Quantum Approaches on the Inhibition of C1018 Carbon Steel Corrosion in Acidic Medium Containing Chloride Using Newly Synthesized Phenolic Schiff Bases Compounds

Authors: Hany M. Abd El-Lateef

Abstract:

Two novel Schiff bases, 5-bromo-2-[(E)-(pyridin-3-ylimino) methyl] phenol (HBSAP) and 5-bromo-2-[(E)-(quinolin-8-ylimino) methyl] phenol (HBSAQ) have been synthesized. They have been characterized by elemental analysis and spectroscopic techniques (UV–Vis, IR and NMR). Moreover, the molecular structure of HBSAP and HBSAQ compounds are determined by single crystal X-ray diffraction technique. The inhibition activity of HBSAP and HBSAQ for carbon steel in 3.5 %NaCl+0.1 M HCl for both short and long immersion time, at different temperatures (20-50 ºC), was investigated using electrochemistry and surface characterization. The potentiodynamic polarization shows that the inhibitors molecule is more adsorbed on the cathodic sites. Its efficiency increases with increasing inhibitor concentrations (92.8 % at the optimal concentration of 10-3 M for HBSAQ). Adsorption of the inhibitors on the carbon steel surface was found to obey Langmuir’s adsorption isotherm with physical/chemical nature of the adsorption, as it is shown also by scanning electron microscopy. Further, the electronic structural calculations using quantum chemical methods were found to be in a good agreement with the results of the experimental studies.

Keywords: carbon steel, Schiff bases, corrosion inhibition, SEM, electrochemical techniques

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2226 Human LACE1 Functions Pro-Apoptotic and Interacts with Mitochondrial YME1L Protease

Authors: Lukas Stiburek, Jana Cesnekova, Josef Houstek, Jiri Zeman

Abstract:

Cellular function depends on mitochondrial function and integrity that is therefore maintained by several classes of proteins possessing chaperone and/or proteolytic activities. In this work, we focused on characterization of LACE1 (lactation elevated 1) function in mitochondrial protein homeostasis maintenance. LACE1 is the human homologue of yeast mitochondrial Afg1 ATPase, a member of SEC18-NSF, PAS1, CDC48-VCP, TBP family. Yeast Afg1 was shown to be involved in mitochondrial complex IV biogenesis, and based on its similarity with CDC48 (p97/VCP) it was suggested to facilitate extraction of polytopic membrane proteins. Here we show that LACE1, which is a mitochondrial integral membrane protein, exists as part of three complexes of approx. 140, 400 and 500 kDa and is essential for maintenance of fused mitochondrial reticulum and lamellar cristae morphology. Using affinity purification of LACE1-FLAG expressed in LACE1 knockdown background we show that the protein physically interacts with mitochondrial inner membrane protease YME1L. We further show that human LACE1 exhibits significant pro-apoptotic activity and that the protein is required for normal function of the mitochondrial respiratory chain. Thus, our work establishes LACE1 as a novel factor with the crucial role in mitochondrial homeostasis maintenance.

Keywords: LACE1, mitochondria, apoptosis, protease

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2225 Selective Effect of Occipital Alpha Transcranial Alternating Current Stimulation in Perception and Working Memory

Authors: Andreina Giustiniani, Massimiliano Oliveri

Abstract:

Rhythmic activity in different frequencies could subserve distinct functional roles during visual perception and visual mental imagery. In particular, alpha band activity is thought to play a role in active inhibition of both task-irrelevant regions and processing of non-relevant information. In the present blind placebo-controlled study we applied alpha transcranial alternating current stimulation (tACS) in the occipital cortex both during a basic visual perception and a visual working memory task. To understand if the role of alpha is more related to a general inhibition of distractors or to an inhibition of task-irrelevant regions, we added a non visual distraction to both the tasks.Sixteen adult volunteers performed both a simple perception and a working memory task during 10 Hz tACS. The electrodes were placed over the left and right occipital cortex, the current intensity was 1 mA peak-to-baseline. Sham stimulation was chosen as control condition and in order to elicit the skin sensation similar to the real stimulation, electrical stimulation was applied for short periods (30 s) at the beginning of the session and then turned off. The tasks were split in two sets, in one set distracters were included and in the other set, there were no distracters. Motor interference was added by changing the answer key after subjects completed the first set of trials.The results show that alpha tACS improves working memory only when no motor distracters are added, suggesting a role of alpha tACS in inhibiting non-relevant regions rather than in a general inhibition of distractors. Additionally, we found that alpha tACS does not affect accuracy and hit rates during the visual perception task. These results suggest that alpha activity in the occipital cortex plays a different role in perception and working memory and it could optimize performance in tasks in which attention is internally directed, as in this working memory paradigm, but only when there is not motor distraction. Moreover, alpha tACS improves working memory performance by means of inhibition of task-irrelevant regions while it does not affect perception.

Keywords: alpha activity, interference, perception, working memory

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2224 Determination of Inactivation and Recovery of Saccharomyces cerevisiae Cells after the Gas-Phase Plasma Treatment

Authors: Z. Herceg, V. Stulic, T. Vukusic, A. Rezek Jambrak

Abstract:

Gas phase plasma treatment is a new nonthermal technology used for food and water decontamination. In this study, we have investigated influence of the gas phase plasma treatment on yeast cells of S. cerevisiae. Sample was composed of 10 mL of yeast suspension and 190 mL of 0.01 M NaNO₃ with a medium conductivity of 100 µS/cm. Samples were treated in a glass reactor with a point- to-plate electrode configuration (high voltage electrode-titanium wire in the gas phase and grounded electrode in the liquid phase). Air or argon were injected into the headspace of the reactor at the gas flow of 5 L/min. Frequency of 60, 90 and 120 Hz, time of 5 and 10 min and positive polarity were defined parameters. Inactivation was higher with the applied higher frequency, longer treatment time and injected argon. Inactivation was not complete which resulted in complete recovery. Cellular leakage (260 nm and 280 nm) was higher with a longer treatment time and higher frequency. Leakage at 280 nm which defines a leakage of proteins was higher than leakage at 260 nm which defines a leakage of nucleic acids. The authors would like to acknowledge the support by Croatian Science Foundation and research project 'Application of electrical discharge plasma for preservation of liquid foods'.

Keywords: Saccharomyces cerevisiae, inactivation, gas-phase plasma treatment, cellular leakage

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2223 Biosynthesis of Natural and Halogenated Plant Alkaloids in Yeast

Authors: Beata J. Lehka, Samuel A. Bradley, Frederik G. Hansson, Khem B. Adhikari, Daniela Rago, Paulina Rubaszka, Ahmad K. Haidar, Ling Chen, Lea G. Hansen, Olga Gudich, Konstantina Giannakou, Yoko Nakamura, Thomas Dugé de Bernonville, Konstantinos Koudounas, Sarah E. O’Connor, Vincent Courdavault, Jay D. Keasling, Jie Zhang, Michael K. Jensen

Abstract:

Monoterpenoid indole alkaloids (MIAs) represent a large class of natural plant products with marketed pharmaceutical activities against a wide range of applications, including cancer and mental disorders. Halogenated MIAs have shown improved pharmaceutical properties; however, characterisation and synthesis of new-to-nature halogenated MIAs remain a challenge in slow-growing plants with limited genetic tractability. Here, we demonstrate a platform for de novo biosynthesis of two bioactive MIAs, serpentine and alstonine, in baker’s yeast Saccharomyces cerevisiae, reaching titers of 8.85 mg/L and 4.48 mg/L, respectively, when cultivated in fed-batch micro bioreactors. Using this MIA biosynthesis platform, we undertake a systematic exploration of the derivative space surrounding these compounds and produce halogenated MIAs. The aim of the current study is to develop a fermentation process for halogenated MIAs.

Keywords: monoterpenoid indole alkaloids, Saccharomyces cerevisiae, halogenated derivatives, fermentation

Procedia PDF Downloads 210