Search results for: biological phosphate fertilizer (fertile 2)
Commenced in January 2007
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Edition: International
Paper Count: 3087

Search results for: biological phosphate fertilizer (fertile 2)

2157 Influence of Digestate Fertilization on Soil Microbial Activity, Greenhouse Gas Emissions and Yield

Authors: M. Doyeni, S. Suproniene, V. Tilvikiene

Abstract:

Agricultural wastes contribute significantly to global climate change through greenhouse gas emissions if not adequately recycled and sustainably managed. A recurring agricultural waste is livestock wastes that have consistently served as feedstock for biogas systems. The objective of this study was to access the influence of digestate fertilization on soil microbial activity and greenhouse gas emissions in agricultural fields. Wheat (Triticum spp. L.) was fertilized with different types of animal wastes digestates (organic fertilizers) and mineral nitrogen (inorganic fertilizer) for three years. The 170 kg N ha⁻¹ presented in digestates were split fertilized at an application rate of 90 and 80 kg N ha⁻¹. The soil microorganism activity could be predicted significantly using the dehydrogenase activity and soil microbial biomass carbon. By combining the two different monitoring approaches, the different methods applied in this study were sensitive to enzymatic activities and organic carbon in the living component of the soil organic matter. The emissions of greenhouse gasses (carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O) were monitored directly by a static chamber system. The soil and environmental variables were measured to determine their influence on greenhouse gas emissions. Emission peaks was observed in N₂O and CO₂ after the first application of fertilizers with the emissions flattening out over the cultivating season while CH₄ emission was negligible with no apparent patterns observed. Microbial biomass carbon and dehydrogenase activity were affected by the fertilized organic digestates. A significant difference was recorded between the control and the digestate treated soils for the microbial biomass carbon and dehydrogenase. Results also showed individual and cumulative emissions of CO₂, CH₄ and N₂O from the digestates were relatively low suggesting the digestate fertilization can be an efficient method for improving soil quality and reducing greenhouse gases from agricultural sources in temperate climate conditions.

Keywords: greenhouse gas emission, manure digestate, soil microbial activity, yield

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2156 Hydrodynamics of Periphyton Biofilters in Recirculating Aquaculture

Authors: Adam N. Bell, Sarina J. Ergas, Michael Nystrom, Nathan P. Brennan, Kevan L. Main

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Integrated Multi-Trophic Aquaculture systems (IMTA) have the potential to improve the sustainability of seafood production, generate organic fertilizer and feed, remove waste discharges and reduce energy use. IMTA can include periphyton biofilters where algae and microbes grow on surfaces, along with caught detritus and amphipods. Periphyton biofilters provide many advantages: nitrification, denitrification, primary production and ecological diversity. The goal of this study was to determine how biofilter hydraulic residence time (τ) effects periphyton biomass production, dissolved oxygen (DO) and nutrient removal. A pilot scale recirculating aquaculture system (RAS) was designed, constructed and operated at different hydraulic residence times (τ= 1, 2, 4, 6, 8 hours per tank). For each τ, a conservative tracer study was conducted to investigate system hydrodynamics. Data on periphyton weights, pH, nitrogen species, phosphorus, temperature and DO were collected. The tracer study for τ =1 hour revealed that the normalized time < τ, indicating short-circuiting. Periphyton biomass production rate was relatively unaffected by τ (R_e<1 for all τ). Average ammonia nitrogen removal was > 75% for all trials. Nitrate and nitrite did not accumulate in the RAS for τ≥4 hours due to enhanced denitrification in anoxic zones. For τ≥4 hours DO concentration was at a maximum of 4 mg L-1 after 14:00, and decreased to 0 mg L-1 during nighttime. At τ=1 hour, the RAS stayed > 2 mg L-1 and DO was more evenly distributed. For the validation trial, the culture tank was stocked with Centropomus undecimalis (common snook) and the system was operated at τ= 1 hr. Preliminary results showed that a RAS with an integrated periphyton biofilter could support fish health with low nutrient concentrations DO > 6 mg L-1.

Keywords: sustainable aquaculture, resource recovery, nitrogen, microalgae, hydrodynamics, integrated multi-trophic aquaculture

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2155 Membrane Bioreactor for Wastewater Treatment and Reuse

Authors: Sarra Kitanou

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Water recycling and reuse is an effective measure to solve the water stress problem. The sustainable use of water resource has become a national development strategy in Morocco. A key aspect of improving overall sustainability is the potential for direct wastewater effluent reuse. However, the hybrid technology membrane bioreactors (MBR) have been identified as an attractive option for producing high quality and nutrient-rich effluents for wastewater treatment. It is based on complex interactions between biological processes, filtration process and rheological properties of the liquid to be treated. Currently, with the evolution of wastewater treatment projects in Morocco, the MBR technology can be used as a technology treating different types of wastewaters and to produce effluent with suitable quality for reuse. However, the energetic consumption of this process is a great concern, which can limit the development and implementation of this technology. In this investigation, the electric energy consumption of an ultrafiltration membrane bioreactor process in domestic wastewater treatment is evaluated and compared to some MBR installations based on literature review. Energy requirements of the MBR are linked to operational parameters and reactor performance. The analysis of energy consumption shows that the biological aeration and membrane filtration are more energy consuming than the other components listed as feed and recirculation pumps. Biological aeration needs 53% of the overall energetic consumption and the specific energy consumption for membrane filtration is about 25%. However, aeration is a major energy consumer, often exceeding 50% share of total energy consumption. The optimal results obtained on the MBR process (pressure p = 1.15 bar), hydraulic retention time (15 h) showed removal efficiencies up to 90% in terms of organic compounds removal, 100% in terms of suspended solids presence and up to 80% reduction of total nitrogen and total phosphorus. The effluent from this MBR system could be considered as qualified for irrigation reuse, showing its potential application in the future.

Keywords: hybrid process, membrane bioreactor, wastewater treatment, reuse

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2154 Biological Methods to Control Parasitic Weed Phelipanche ramosa L. Pomel in the Field Tomato Crop

Authors: F. Lops, G. Disciglio, A. Carlucci, G. Gatta, L. Frabboni, A. Tarantino, E. Tarantino

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Phelipanche ramosa L. Pomel is a root holoparasitic weed plant of many cultivations, particularly of tomato (Lycopersicum esculentum L.) crop. In Italy, Phelipanche problem is increasing, both in density and in acreage. The biological control of this parasitic weed involves the use of living organisms as numerous fungi and bacteria that can infect the parasitic weed, while it may improve the crop growth. This paper deals with the biocontrol with microorganism, including Arbuscular mycorrhizal (AM) fungi and fungal pathogens as Fusarium oxisporum spp. Colonization of crop roots by AM fungi can provide protection of crops against parasitic weeds because of a reduction in their seed germination and attachment, while F. oxisporum, isolated from diseased broomrape tubercles, proved to be highly virulent on P. ramosa. The experimental trial was carried out in open field at Foggia province (Apulia Region, Southern Italy), during the spring-summer season 2016, in order to evaluate the effect of four biological treatments: AM fungi and Fusarium oxisporum applied in the soil alone or combined together, and Rizosum Max® product, compared with the untreated control, to reduce the P. ramosa infestation in processing tomato crop. The principal results to be drawn from this study under field condition, in contrast of those reported previously under laboratory and greenhouse conditions, show that both AM fungi and F. oxisporum do not provide the reduction of the number of emerged shoots of P. ramosa. This can arise probably from the low efficacy seedling of the agent pathogens for the control of this parasite in the field. On the contrary, the Rizosum Max® product, containing AM fungi and some rizophere bacteria combined with several minerals and organic substances, appears to be most effective for the reduction of P. ramosa infestation.

Keywords: Arbuscular mycorrhized fungi, biocontrol methods, Phelipanche ramosa, tomato crop

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2153 Biostimulant and Abiotic Plant Stress Interactions in Malting Barley: A Glasshouse Study

Authors: Conor Blunt, Mariluz del Pino-de Elias, Grace Cott, Saoirse Tracy, Rainer Melzer

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The European Green Deal announced in 2021 details agricultural chemical pesticide use and synthetic fertilizer application to be reduced by 50% and 20% by 2030. Increasing and maintaining expected yields under these ambitious goals has strained the agricultural sector. This intergovernmental plan has identified plant biostimulants as one potential input to facilitate this new phase of sustainable agriculture; these products are defined as microorganisms or substances that can stimulate soil and plant functioning to enhance crop nutrient use efficiency, quality and tolerance to abiotic stresses. Spring barley is Ireland’s most widely sown tillage crop, and grain destined for malting commands the most significant market price. Heavy erratic rainfall is forecasted in Ireland’s climate future, and barley is particularly susceptible to waterlogging. Recent findings suggest that plant receptivity to biostimulants may depend on the level of stress inflicted on crops to elicit an assisted plant response. In this study, three biostimulants of different genesis (seaweed, protein hydrolysate and bacteria) are applied to ‘RGT Planet’ malting barley fertilized at three different rates (0 kg/ha, 40 kg/ha, 75 kg/ha) of calcium ammonium nitrogen (27% N) under non-stressed and waterlogged conditions. This 4x3x2 factorial trial design was planted in a completed randomized block with one plant per experimental unit. Leaf gas exchange data and key agronomic and grain quality parameters were analyzed via ANOVA. No penalty on productivity was evident on plants receiving 40 kg/ha of N and bio stimulant compared to 75 kg/ha of N treatments. The main effects of nitrogen application and waterlogging provided the most significant variation in the dataset.

Keywords: biostimulant, Barley, malting, NUE, waterlogging

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2152 Development and Validation Method for Quantitative Determination of Rifampicin in Human Plasma and Its Application in Bioequivalence Test

Authors: Endang Lukitaningsih, Fathul Jannah, Arief R. Hakim, Ratna D. Puspita, Zullies Ikawati

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Rifampicin is a semisynthetic antibiotic derivative of rifamycin B produced by Streptomyces mediterranei. RIF has been used worldwide as first line drug-prescribed throughout tuberculosis therapy. This study aims to develop and to validate an HPLC method couple with a UV detection for determination of rifampicin in spiked human plasma and its application for bioequivalence study. The chromatographic separation was achieved on an RP-C18 column (LachromHitachi, 250 x 4.6 mm., 5μm), utilizing a mobile phase of phosphate buffer/acetonitrile (55:45, v/v, pH 6.8 ± 0.1) at a flow of 1.5 mL/min. Detection was carried out at 337 nm by using spectrophotometer. The developed method was statistically validated for the linearity, accuracy, limit of detection, limit of quantitation, precise and specifity. The specifity of the method was ascertained by comparing chromatograms of blank plasma and plasma containing rifampicin; the matrix and rifampicin were well separated. The limit of detection and limit of quantification were 0.7 µg/mL and 2.3 µg/mL, respectively. The regression curve of standard was linear (r > 0.999) over a range concentration of 20.0 – 100.0 µg/mL. The mean recovery of the method was 96.68 ± 8.06 %. Both intraday and interday precision data showed reproducibility (R.S.D. 2.98% and 1.13 %, respectively). Therefore, the method can be used for routine analysis of rifampicin in human plasma and in bioequivalence study. The validated method was successfully applied in pharmacokinetic and bioequivalence study of rifampicin tablet in a limited number of subjects (under an Ethical Clearance No. KE/FK/6201/EC/2015). The mean values of Cmax, Tmax, AUC(0-24) and AUC(o-∞) for the test formulation of rifampicin were 5.81 ± 0.88 µg/mL, 1.25 hour, 29.16 ± 4.05 µg/mL. h. and 29.41 ± 4.07 µg/mL. h., respectively. Meanwhile for the reference formulation, the values were 5.04 ± 0.54 µg/mL, 1.31 hour, 27.20 ± 3.98 µg/mL.h. and 27.49 ± 4.01 µg/mL.h. From bioequivalence study, the 90% CIs for the test formulation/reference formulation ratio for the logarithmic transformations of Cmax and AUC(0-24) were 97.96-129.48% and 99.13-120.02%, respectively. According to the bioequivamence test guidelines of the European Commission-European Medicines Agency, it can be concluded that the test formulation of rifampicin is bioequivalence with the reference formulation.

Keywords: validation, HPLC, plasma, bioequivalence

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2151 The Use of Beneficial Microorganisms from Diverse Environments for the Management of Aflatoxin in Maize

Authors: Mathias Twizeyimana, Urmila Adhikari, Julius P. Sserumaga, David Ingham

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The management of aflatoxins (naturally occurring toxins produced by certain fungi, most importantly Aspergillus flavus and A. parasiticus) relies mostly on the use of best cultural practices and, in some cases, the use of the biological control consisting of atoxigenic strains inhibiting the toxigenic strains through competition resulting in considerable toxin reduction. At AgBiome, we have built a core collection of over 100,000 fully sequenced microbes from diverse environments and employ both the microbes and their sequences in the discovery of new biological products for disease and pest control. The most common approach to finding beneficial microbes consists of isolating microorganisms from samples collected from diverse environments, selecting antagonistic strains through empirical screening, studying modes of action, and stabilization through the formulation of selected microbial isolates. A total of 608 diverse bacterial strains were screened using a high-throughput assay (48-well assay) to identify strains that inhibit toxigenic A. flavus growth on maize kernels. Active strains in 48-well assay had their pathogen inhibiting activity confirmed using the Flask Assay and were concurrently tested for their ability to reduce the aflatoxin content in maize grains. Strains with best growth inhibition and reduction of aflatoxin were tested in the greenhouse and field trials. From the field trials, three bacterial strains, AFS000009 (Pseudomonas chlororaphis), AFS032321 (Bacillus subtilis), AFS024683 (Bacillus velezensis), had aflatoxin concentrations (ppb) values that were significantly lower than those of inoculated control. The identification of biological products with high efficacy in inhibiting pathogen growth and eventually reducing the aflatoxin content will provide a valuable alternative to control strategies used in aflatoxin contamination management.

Keywords: aflatoxin, microorganism bacteria, biocontrol, beneficial microbes

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2150 Analysis of Indoor Air Quality and Sick Building Syndrome in Control Room Oil Gas Refinery

Authors: Dessy Laksyana Utami

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The sick building syndrome comprises of various nonspecific symptoms that occur in the occupants of a building. It is commonly increases sickness absenteeism and causes a decrease in productivity of the workers. Evidence suggests that what is called the Sick Building Syndrome are at least three separate entities, which has at least one cause. The following are some of the factors that might be primarily responsible for Sick Building Syndrome such as: Chemical contaminants, Biological contaminants, Inadequate ventilation and Electromagnetic radiation. In many cases it is due to insufficient maintenance of the HVAC (heating, ventilation, air conditioning) system in the building. As this syndrome is increasingly becoming a major occupational hazard. It was used the analytic cross-sectional design. Based on data obtained 80% of respondents reported significant ongoing health problems in the eyes, head, and the nose. 60% had bad symptoms in the throat, the stomach and cough, 50% had gastrointestinal disorders, 40% fatigue and 25% occurred all symptoms sick building syndrome. The 40 respondents were recruited to the study, with a mean age of 35 years (range 20-55). To support the evidence of Sick Building Syndrome, further checks are needed for some of the factors in next research, i.e. measurement of Chemical contaminants, Biological contaminants, inadequate ventilation & Electromagnetic radiation.

Keywords: indoor air pollution, sick building syndrome, indoor air quality, oil gas polution

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2149 Mueller Matrix Polarimetry for Analysis Scattering Biological Fluid Media

Authors: S. Cherif, A. Medjahed, M. Bouafia, A. Manallah

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A light wave is characterized by 4 characteristics: its amplitude, its frequency, its phase and the direction of polarization of its luminous vector (the electric field). It is in this last characteristic that we will be interested. The polarization of the light was introduced in order to describe the vectorial behavior of the light; it describes the way in which the electric field evolves in a point of space. Our work consists in studying diffusing mediums. Different types of biological fluids were selected to study the evolution of each with increasing scattering power of the medium, and in the same time to make a comparison between them. When crossing these mediums, the light undergoes modifications and/or deterioration of its initial state of polarization. This phenomenon is related to the properties of the medium, the idea is to compare the characteristics of the entering and outgoing light from the studied medium by a white light. The advantage of this model is that it is experimentally accessible workable intensity measurements with CCD sensors and allows operation in 2D. The latter information is used to discriminate some physical properties of the studied areas. We chose four types of milk to study the evolution of each with increasing scattering power of the medium.

Keywords: light polarization, Mueller matrix, Mueller images, diffusing medium, milk

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2148 Bioefficacy of Ocimum sanctum on Reproductive Performance of Red Cotton Bug, Dysdercus koenigii (Heteroptera: Pyrrhocoriedae)

Authors: Kamal Kumar Gupta, Sunil Kayesth

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Dysdercus koenigii is serious pest of cotton and other malvaceous crop. Present research work aimed at ecofriendly approach for management of pest by plant extracts. The impact of Ocimum sanctum was studied on reproductive performance of Dysdercus koenigii. The hexane extract of Ocimum leaves was prepared by ‘cold extraction method’. The newly emerged fifth instar nymphs were exposed to the extract of concentrations ranging from 0.1% to 0.00625% by ‘thin film residual method’ for a period of 24h. Reproductive fitness of the adults emerged from the treated nymphs was evaluated by assessing their courtship behaviour, oviposition behaviour, and fertility. The studies indicated that treatment of Dysdercus with the hexane extract of Ocimum altered their courtship behaviour. Consequently, the treated males exhibited less sexual activity, performed fewer mounting attempts, increased time to mate and showed decreased percent successful mating. The females often rejected courting treated male by shaking the abdomen. Similarly, the treated females in many cases remained non-receptive to the courting male. Premature termination of mating in the mating pairs prior to insemination further decreased the mating success of the treated adults. Maximum abbreviation of courtship behaviour was observed in the experimental set up where both the males and the females were treated. Only females which mate successfully were observed for study of oviposition behaviour. The treated females laid lesser number of egg batches and eggs in their life span. The eggs laid by these females were fertile indicating insemination of the female. However, percent hatchability was lesser than control. The effects of hexane extract were dose dependent. Treatment with 0.1% and 0.05% extract altered courtship behaviour. Doses of concentrations less than 0.05% did not affect courtship behaviour but altered the oviposition behaviour and fertility. Significant reduction in the fecundity and fertility was observed in the treatments at concentration as low as 0.00625%. The GCMS analysis of the extract revealed a plethora of phytochemicals including juvenile hormone mimics, and the intermediates of juvenile hormone biosynthesis. Therefore, some of these compounds individually or synergistically impair reproductive behaviour of Dysdercus. Alteration of courtship behaviour and suppression of fecundity and fertility with the help of plant extracts has wide potentials in suppression of pest population and ‘integrated pest management’.

Keywords: courtship behaviour, Dysdercus koenigii, Ocimum sanctum, oviposition behaviour

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2147 Vertebrate Model to Examine the Biological Effectiveness of Different Radiation Qualities

Authors: Rita Emília Szabó, Róbert Polanek, Tünde Tőkés, Zoltán Szabó, Szabolcs Czifrus, Katalin Hideghéty

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Purpose: Several feature of zebrafish are making them amenable for investigation on therapeutic approaches such as ionizing radiation. The establishment of zebrafish model for comprehensive radiobiological research stands in the focus of our investigation, comparing the radiation effect curves of neutron and photon irradiation. Our final aim is to develop an appropriate vertebrate model in order to investigate the relative biological effectiveness of laser driven ionizing radiation. Methods and Materials: After careful dosimetry series of viable zebrafish embryos were exposed to a single fraction whole-body neutron-irradiation (1,25; 1,875; 2; 2,5 Gy) at the research reactor of the Technical University of Budapest and to conventional 6 MeV photon beam at 24 hour post-fertilization (hpf). The survival and morphologic abnormalities (pericardial edema, spine curvature) of each embryo were assessed for each experiment at 24-hour intervals from the point of fertilization up to 168 hpf (defining the dose lethal for 50% (LD50)). Results: In the zebrafish embryo model LD50 at 20 Gy dose level was defined and the same lethality were found at 2 Gy dose from the reactor neutron beam resulting RBE of 10. Dose-dependent organ perturbations were detected on macroscopic (shortening of the body length, spine curvature, microcephaly, micro-ophthalmia, micrognathia, pericardial edema, and inhibition of yolk sac resorption) and microscopic (marked cellular changes in skin, cardiac, gastrointestinal system) with the same magnitude of dose difference. Conclusion: In our observations, we found that zebrafish embryo model can be used for investigating the effects of different type of ionizing radiation and this system proved to be highly efficient vertebrate model for preclinical examinations.

Keywords: ionizing radiation, LD50, relative biological effectiveness, zebrafish embryo

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2146 Recovery of Au and Other Metals from Old Electronic Components by Leaching and Liquid Extraction Process

Authors: Tomasz Smolinski, Irena Herdzik-Koniecko, Marta Pyszynska, M. Rogowski

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Old electronic components can be easily found nowadays. Significant quantities of valuable metals such as gold, silver or copper are used for the production of advanced electronic devices. Old useless electronic device slowly became a new source of precious metals, very often more efficient than natural. For example, it is possible to recover more gold from 1-ton personal computers than seventeen tons of gold ore. It makes urban mining industry very profitable and necessary for sustainable development. For the recovery of metals from waste of electronic equipment, various treatment options based on conventional physical, hydrometallurgical and pyrometallurgical processes are available. In this group hydrometallurgy processes with their relatively low capital cost, low environmental impact, potential for high metal recoveries and suitability for small scale applications, are very promising options. Institute of Nuclear Chemistry and Technology has great experience in hydrometallurgy processes especially focused on recovery metals from industrial and agricultural wastes. At the moment, urban mining project is carried out. The method of effective recovery of valuable metals from central processing units (CPU) components has been developed. The principal processes such as acidic leaching and solvent extraction were used for precious metals recovery from old processors and graphic cards. Electronic components were treated by acidic solution at various conditions. Optimal acid concentration, time of the process and temperature were selected. Precious metals have been extracted to the aqueous phase. At the next step, metals were selectively extracted by organic solvents such as oximes or tributyl phosphate (TBP) etc. Multistage mixer-settler equipment was used. The process was optimized.

Keywords: electronic waste, leaching, hydrometallurgy, metal recovery, solvent extraction

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2145 Consequences of Some Remediative Techniques Used in Sewaged Soil Bioremediation on Indigenous Microbial Activity

Authors: E. M. Hoballah, M. Saber, A. Turky, N. Awad, A. M. Zaghloul

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Remediation of cultivated sewage soils in Egypt become an important aspect in last decade for having healthy crops and saving the human health. In this respect, a greenhouse experiment was conducted where contaminated sewage soil was treated with modified forms of 2% bentonite (T1), 2% kaolinite (T2), 1% bentonite+1% kaolinite (T3), 2% probentonite (T4), 2% prokaolinite (T5), 1% bentonite + 0.5% kaolinite + 0.5% rock phosphate (RP) (T6), 2% iron oxide (T7) and 1% iron oxide + 1% RP (T8). These materials were applied as remediative materials. Untreated soil was also used as a control. All soil samples were incubated for 2 months at 25°C at field capacity throughout the whole experiment. Carbon dioxide (CO2) efflux from both treated and untreated soils as a biomass indicator was measured through the incubation time and kinetic parameters of the best fitted models used to describe the phenomena were taken to evaluate the succession of sewaged soils remediation. The obtained results indicated that according to the kinetic parameters of used models, CO2 effluxes from remediated soils was significantly decreased compared to control treatment with variation in rate values according to type of remediation material applied. In addition, analyzed microbial biomass parameter showed that Ni and Zn were the most potential toxic elements (PTEs) that influenced the decreasing order of microbial activity in untreated soil. Meanwhile, Ni was the only influenced pollutant in treated soils. Although all applied materials significantly decreased the hazards of PTEs in treated soil, modified bentonite was the best treatment compared to other used materials. This work discussed different mechanisms taking place between applied materials and PTEs founded in the studied sewage soil.

Keywords: remediation, potential toxic elements, soil biomass, sewage

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2144 Development of Soil Test Kits to Determine Organic Matter Available Phosphorus and Exchangeable Potassium in Thailand

Authors: Charirat Kusonwiriyawong, Supha Photichan, Wannarut Chutibutr

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Soil test kits for rapid analysis of the organic matter, available phosphorus and exchangeable potassium were developed to drive a low-cost field testing kit to farmers. The objective was to provide a decision tool for improving soil fertility. One aspect of soil test kit development was ease of use which is a time requirement for completing organic matter, available phosphorus and exchangeable potassium test in one soil sample. This testing kit required only two extractions and utilized no filtration consuming approximately 15 minutes per sample. Organic matter was principally created by oxidizing carbon KMnO₄ using the standard color chart. In addition, modified single extractant (Mehlich I) was applied to extract available phosphorus and exchangeable potassium. Molybdenum blue method and turbidimetric method using standard color chart were adapted to analyze available phosphorus and exchangeable potassium, respectively. Modified single extractant using in soil test kits were highly significant matching with analytical laboratory results (r=0.959** and 0.945** for available phosphorus and exchangeable potassium, respectively). Linear regressions were statistically calculated between modified single extractant and standard laboratory analysis (y=0.9581x-12.973 for available phosphorus and y=0.5372x+15.283 for exchangeable potassium, respectively). These equations were calibrated to formulate a fertilizer rate recommendation for specific corps. To validate quality, soil test kits were distributed to farmers and extension workers. We found that the accuracy of soil test kits were 71.0%, 63.9% and 65.5% for organic matter, available phosphorus, and exchangeable potassium, respectively. The quantitative survey was also conducted in order to assess their satisfaction with soil test kits. The survey showed that more than 85% of respondents said these testing kits were more convenient, economical and reliable than the other commercial soil test kits. Based upon the finding of this study, soil test kits can be another alternative for providing soil analysis and fertility recommendations when a soil testing laboratory is not available.

Keywords: available phosphorus, exchangeable potassium, modified single extractant, organic matter, soil test kits

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2143 Synthesis, Biological Evaluation and Molecular Modeling Studies on Chiral Chloroquine Analogues as Antimalarial Agents

Authors: Srinivasarao Kondaparla, Utsab Debnath, Awakash Soni, Vasantha Rao Dola, Manish Sinha, Kumkum Kumkum Srivastava, Sunil K. Puri, Seturam B. Katti

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In a focused exploration, we have designed synthesized and biologically evaluated chiral conjugated new chloroquine (CQ) analogs with substituted piperazines as antimalarial agents. In vitro as well as in vivo studies revealed that compound 7c showed potent activity [for in vitro IC₅₀= 56.98nM (3D7), 97.76nM (K1); for in vivo (up to at the dose of 12.5 mg/kg); SI = 3510] as a new lead of antimalarial agent. Other compounds 6b, 6d, 7d, 7h, 8c, 8d, 9a, and 9c are also showing moderate activity against CQ-sensitive (3D7) strain and superior activity against resistant (K1) strain of P. falciparum. Furthermore, we have carried out docking and 3D-QSAR studies of all in-house data sets (168 molecules) of chiral CQ analogs to explain the structure activity relationships (SAR). Our new findings specified the significance of H-bond interaction with the side chain of heme for biological activity. In addition, the 3D-QSAR study against 3D7 strain indicated the favorable and unfavorable sites of CQ analogs for incorporating steric, hydrophobic and electropositive groups to improve the antimalarial activity.

Keywords: piperazines, CQ-sensitive strain-3D7, in-vitro and in-vivo assay, docking, 3D-QSAR

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2142 Urban Agriculture among Households of Makurdi Metropolis of Benue State, Nigeria: Key Challenges

Authors: Evangeline Mbah, Margret Okeke, Agbo Joseph

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Agriculture was primarily a rural activity in Nigeria, but due to increasing demand for food and jobs for many urban dwellers, it became necessary for urban households to embark on farming as a means of improving household food security and additional income for economic empowerment. Urban agriculture serves as a veritable tool for poverty reduction among people living in urban areas mostly low-income earners and unemployed. The survey was conducted to identify key challenges encountered by households in Makurdi metropolis of Benue state, Nigeria who are engaged in urban agriculture. A well-structured questionnaire was used to collect data from a sample of respondents used for the study. Data were analyzed using frequency, percentage, mean score and standard deviation. Results show that a greater percentage (46.0%) of the respondents engaged in cultivation of leafy vegetable, 22.0% cultivated cassava, 21.0% planted sweet potato, 18.0% cultivated tomato while 56.0% reared poultry, 23.0% kept goat, among others. Sources of agricultural information indicated by the respondents were family members/relations (85.0%), friends/neighbours (73.0%), radio (68.0%), extension agents (57.0%), etc. Major challenges encountered by the respondents in urban agriculture include inadequate size of farmland (M= 2.72), lack of access to credit facilities (M= 2.63), lack of funds (M= 2.50), high cost of labour (M= 2.49), insecurity of lands (M= 2.46), theft of crops at maturity (M= 2.38), lack of farm inputs such as improved varieties of seeds, fertilizer and exotic breeds of livestock (M= 2.23), destruction of crops by stray farm animals (M= 1.96), among others. The study recommends that there is a need for adequate provision of farm inputs by the government at all levels at a subsidized rate in order to reduce the cost of production and enhance optimum productivity.

Keywords: urban, agriculture, household, challenges, Makurdi, Nigeria

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2141 Evaluation of the Effects of Lead on Some Physiological and Hormonal Biomarkeurs among Workers

Authors: Mansouri Ouarda, Adbdennour Cherif, Boukarma Ziad

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Environmental and biological monitoring are used for the evaluation of exposure to industrial chemicals, and provide a tool for assessing workers’ exposure to chemicals. The organs or tissues where the first biological effects can be observed with increasing amounts of lead toxicity. This study aims at evaluating the effect of the metal element-trace; lead, on the sex hormones in male workers, exposed to this metal on the level of the manufacturing plant of lead accumulators. The results indicate a significant reduction of the testosterone concentration in exposed workers compared to the control. However, the rate of LH was strongly increased at the individuals exposed to Pb. A significant difference concerning the rate of FSH, the hormone Prolactin and cortisol was recorded. The indicators of the lead poisoning indicate a very highly significant increase in the value of Pbs which vary between (142-796 µg/L) among which 50% of the workers present a high lead poisoning and the value of PPZ which vary between (43-554µg/L). The biochemical parameters show a significant increase in the rate of the créatinine, the urea and the acid urique. The hepatic results show no significant differentiation in the rate of TGO and TGP between both groups of study. However the rates of the enzyme phosphatase alkaline, triglyceride, and cholesterol a significant difference were registered.

Keywords: hormons, parameters, physilogical, Pbs, PPZ

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2140 Improvement of Resistance Features of Anti- Mic Polyaspartic Coating (DTM) Using Nano Silver Particles by Preventing Biofilm Formation

Authors: Arezoo Assarian, Reza Javaherdashti

Abstract:

Microbiologically influenced corrosion (MIC) is an electrochemical process that can affect both metals and non-metals. The cost of MIC can amount to 40% of the cost of corrosion. MIC is enhanced via factors such as but not limited to the presence of certain bacteria and archaea as well as mechanisms such as external electron transfer. There are five methods by which electrochemical corrosion, including MIC, can be prevented, of which coatings are an effective method due to blinding anode, cathode and, electrolyte from each other. Conventional ordinary coatings may themselves become nutrient sources for the bacteria and therefore show low efficiency in dealing with MIC. Recently our works on polyaspartic coating (DTM) have shown promising results, therefore nominating DTM as the most appropriate coating material to manage both MIC and general electrochemical corrosion very efficiently. Nanosilver particles are known for their antimicrobial properties that make them of desirable distractive impacts on any germs. This coating will be formulated based on Nanosilver phosphate and copper II oxide in the resin network and co-reactant. The nanoparticles are light and heat-sensitive agents. The method which is used to keep nanoparticles in the film coating is the encapsulation of active ingredients. By this method, it will prevent incompatibility between different particles. For producing microcapsules, the interfacial cross-linking method will be used. This is achieved by adding an active ingredient to an aqueous solution of the cross-linkable polymer. In this paper, we will first explain the role of coating materials in controlling and preventing electrochemical corrosion. We will explain MIC and some of its fundamental principles, such as bacteria establishment (biofilm) and the role they play in enhancing corrosion via mechanisms such as the establishment of differential aeration cells. Later we will explain features of DTM coatings that highly contribute to preventing biofilm formation and thus microbial corrosion.

Keywords: biofilm, corrosion, microbiologically influenced corrosion(MIC), nanosilver particles, polyaspartic coating (DTM)

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2139 Optimization of Monascus Orange Pigments Production Using pH-Controlled Fed-Batch Fermentation

Authors: Young Min Kim, Deokyeong Choe, Chul Soo Shin

Abstract:

Monascus pigments, commonly used as a natural colorant in Asia, have many biological activities, such as cholesterol level control, anti-obesity, anti-cancer, and anti-oxidant, that have recently been elucidated. Especially, amino acid derivatives of Monascus pigments are receiving much attention because they have higher biological activities than original Monascus pigments. Previously, there have been two ways to produce amino acid derivatives: one-step production and two-step production. However, the one-step production has low purity, and the two-step production—precursor(orange pigments) fermentation and derivatives synthesis—has low productivity and growth rate during its precursor fermentation step. In this study, it was verified that pH is a key factor that affects the stability of orange pigments and the growth rate of Monascus. With an optimal pH profile obtained by pH-stat fermentation, we designed a process of precursor(orange pigments) fermentation that is a pH-controlled fed-batch fermentation. The final concentration of orange pigments in this process increased to 5.5g/L which is about 30% higher than the concentration produced from the previously used precursor fermentation step.

Keywords: cultivation process, fed-batch fermentation, monascus pigments, pH stability

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2138 Sustainable Thermal Energy Storage Technologies: Enhancing Post-Harvest Drying Efficiency in Sub-Saharan Agriculture

Authors: Luís Miguel Estevão Cristóvão, Constâncio Augusto Machanguana, Fernando Chichango, Salvador Grande

Abstract:

Sub-Saharan African nations depend greatly on agriculture, a sector mainly marked by low production. Most of the farmers live in rural areas and employ basic labor-intensive technologies that lead to time inefficiencies and low overall effectiveness. Even with attempts to enhance farmers’ welfare through improved seeds and fertilizers, meaningful outcomes are yet to be achieved due to huge amounts of post-harvest losses. Such losses significantly endanger food security, economic stability, and result in unsustainable agricultural practices because more land, water, labor, energy, fertilizer, and other inputs must be used to produce more food. Drying, as a critical post-harvest process involving simultaneous heat and mass transfer, deserves attention. Among alternative green-energy sources, solar energy-based drying garners attention, particularly for small-scale farmers in remote communities. However, the intermittent nature of solar radiation poses challenges. To address this, energy storage solutions like rock-based thermal energy storage offer cost-effective solutions tailored to the needs of farmers. Methodologically, three solar dryers were constructed of metal, wood, and clay brick. Several tests were carried out with and without energy storage material. Notably, it has been demonstrated that soapstone stands out as a promising material due to its affordability and high specific energy capacity. By implementing these greener technologies, Sub-Saharan African countries could mitigate post-harvest losses, enhance food availability, improve nutrition, and promote sustainable resource utilization.

Keywords: energy storage, food security, post-harvest, solar dryer

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2137 Microarray Data Visualization and Preprocessing Using R and Bioconductor

Authors: Ruchi Yadav, Shivani Pandey, Prachi Srivastava

Abstract:

Microarrays provide a rich source of data on the molecular working of cells. Each microarray reports on the abundance of tens of thousands of mRNAs. Virtually every human disease is being studied using microarrays with the hope of finding the molecular mechanisms of disease. Bioinformatics analysis plays an important part of processing the information embedded in large-scale expression profiling studies and for laying the foundation for biological interpretation. A basic, yet challenging task in the analysis of microarray gene expression data is the identification of changes in gene expression that are associated with particular biological conditions. Careful statistical design and analysis are essential to improve the efficiency and reliability of microarray experiments throughout the data acquisition and analysis process. One of the most popular platforms for microarray analysis is Bioconductor, an open source and open development software project based on the R programming language. This paper describes specific procedures for conducting quality assessment, visualization and preprocessing of Affymetrix Gene Chip and also details the different bioconductor packages used to analyze affymetrix microarray data and describe the analysis and outcome of each plots.

Keywords: microarray analysis, R language, affymetrix visualization, bioconductor

Procedia PDF Downloads 466
2136 Exploration of Industrial Symbiosis Opportunities with an Energy Perspective

Authors: Selman Cagman

Abstract:

A detailed analysis is made within an organized industrial zone (OIZ) that has 1165 production facilities such as manufacturing of furniture, fabricated metal products (machinery and equipment), food products, plastic and rubber products, machinery and equipment, non-metallic mineral products, electrical equipment, textile products, and manufacture of wood and cork products. In this OIZ, a field study is done by choosing some facilities that can represent the whole OIZ sectoral distribution. In this manner, there are 207 facilities included to the site visit, and there is a 17 questioned survey carried out with each of them to assess their inputs, outputs, and waste amounts during manufacturing processes. The survey result identify that MDF/Particleboard and chipboard particles, textile, food, foam rubber, sludge (treatment sludge, phosphate-paint sludge, etc.), plastic, paper and packaging, scrap metal (aluminum shavings, steel shavings, iron scrap, profile scrap, etc.), slag (coal slag), ceramic fracture, ash from the fluidized bed are the wastes come from these facilities. As a result, there are 5 industrial symbiosis projects established with this study. One of the projects is a 2.840 kW capacity Integrated Biomass Based Waste Incineration-Energy Production Facility running on 35.000 tons/year of MDF particles and chipboard waste. Another project is a biogas plant with 225 tons/year whey, 100 tons/year of sesame husk, 40 tons/year of burnt wafer dough, and 2.000 tons/year biscuit waste. These two plants investment costs and operational costs are given in detail. The payback time of the 2.840 kW plant is almost 4 years and the biogas plant is around 6 years.

Keywords: industrial symbiosis, energy, biogas, waste to incineration

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2135 Study of Non-hodgkin’s Lymphoma

Authors: Zidani Abla

Abstract:

Lymphoma is a common type of cancer that affects the lymphatic system, including the lymph nodes, spleen and other associated organs. There are two main types of lymphoma: Hodgkin's lymphoma and non-Hodgkin's lymphoma. The epidemiological, clinical and biological features of lymphoma are poorly studied in Algeria. The main objective of our study is to investigate the epidemiological, clinical, paraclinical, etiological, evolutionary and biological characteristics of non-Hodgkin's lymphoma (NHL) in the hematology department of the University Hospital Center (HUC) of Batna. This is a study of 10 patients diagnosed at Batna University Hospital. 70% were male and 30% female (sex ratio M/F= 2.33). Median age was 51.7 years. Pain, especially abdominal pain, was the main reason for consultation. Stage IV predominated (40%), followed by stage III (20%). Abdominal adenopathies (34%) were the most abundant. Secondary hepatic localization was predominant. Large B-cell NHL predominated, accounting for 60% of cases, followed by small B-cell NHL (30%). Serology for hepatitis B and C, and human immunodeficiency virus (HIV) was negative. Biologically, a predominance of hyperleukocytosis, polynuclear neutrophilic leukocytosis, lymphopenia and hypoalbuminemia were present in the majority of cases. In summary, our results remain to be compared with other works for other periods and other regions in order to generalize lymphoma percentages for the entire Algerian population.

Keywords: non Hodgkin's lymphoma, epidemiology, clinic, biology

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2134 Synthesis, Molecular-Docking, and Biological Evaluation of Thiazolopyrimidine Carboxylates as Potential Antidiabetic and Antibacterial Agents

Authors: Iram Batool, Aamer Saeed, Irfan Zia Qureshi, Ayesha Razzaq, Saima Kalsoom

Abstract:

Heterocyclic compounds analogues and their derivatives have attracted strong interest in medicinal chemistry due to their biological and pharmacological properties. A series of new thiazolopyrimidine carboxylates were conveniently synthesized by one-pot three-component reaction of ethyl acetoacetate, 2-aminothiazole and benzaldehyde substituted with electron-donating and electron-withdrawing groups in order to find some more potent antidiabetic and antibacterial drugs. The structures of synthesized compounds were characterized by elemental analysis, IR, 1H NMR, 13C NMR spectroscopy. An in vitro antidiabetic effect was evaluated in adult male BALB/c mice and antibacterial activities were tested against Micrococcus luteus, Salmonella typhimurium, Bacillus subtilis, Bordetella bronchiseptica and Escherichia coli. Some of the tested compounds proved to possess good to excellent activities more than the reference drugs. An in silico molecular docking was also performed on synthesized compounds. The current study is expected to provide useful insights into the design of antidiabetic and antibacterial drugs and understanding the mechanism by which such drugs interact with RNA and diabetes target and exert their biochemical action.

Keywords: antidiabetic, antibacterial, MOE docking, thiazolopyrimidine

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2133 Biosurfactant-Mediated Nanoparticle Synthesis by Bacillus subtilis

Authors: Satya Eswari Jujjavarapu, Swasti Dhagat, Lata Upadhyay, Reecha Sahu

Abstract:

Silver nanoparticles have a broad range of antimicrobial and antifungal properties ranging from soaps, pastes to sterilization and drug delivery systems. These can be synthesized by physical, chemical and biological methods; biological methods being the most popular owing to their non-toxic nature and reduced energy requirements. Microbial surfactants, produced on the microbial cell surface or excreted extracellularly are an alternative to synthetic surfactants for the production of silver nanoparticles. Hence, they are also called as green molecules. Microbial lipopeptide surfactants (biosurfactant) exhibit anti-tumor and anti-microbial properties and can be used as drug delivery agents. In this study, biosurfactant was synthesized by using a strain of acillus subtilis. The biosurfactant thus produced was analysed by emulsification assay, oil spilling test, and haemolytic test. Biosurfactant-mediated silver nanoparticles were synthesised by microwave irradiation of the culture supernatant and further characterized by UV–vis spectroscopy for a range of 400-600 nm. The UV–vis spectra showed a surface plasmon resonance vibration band at 410 nm corresponding to the peak of silver nanoparticles.

Keywords: biosurfactant, Bacillus subtilis, silver nano particle, lipopeptide

Procedia PDF Downloads 228
2132 Technologies for Phosphorus Removal from Wastewater: Review

Authors: Thandie Veronicah Sima, Moatlhodi Wiseman Letshwenyo

Abstract:

Discharge of wastewater is one of the major sources of phosphorus entering streams, lakes and other water bodies causing undesired environmental problem such as eutrophication. This condition not only puts the ecosystem at risk but also causes severe economic damages. Stringent laws have been developed globally by different bodies to control the level of phosphorus concentrations into receiving environments. In order to satisfy the constraints, a high degree of tertiary treatment or at least a significant reduction of phosphorus concentration is obligatory. This comprehensive review summarizes phosphorus removal technologies, from the most commonly used conventional technologies such as chemical precipitation through metal addition, membrane filtration, reverse osmosis and enhanced biological phosphorus removal using activated sludge system to passive systems such as constructed wetlands and filtration systems. Trends, perspectives and scientific procedures conducted by different researchers have been presented. This review critically evaluates the advantages and limitations behind each of the technologies. Enhancement of passive systems using reactive media such as industrial wastes to provide additional uptake through adsorption or precipitation is also discussed in this article.

Keywords: adsorption, chemical precipitation, enhanced biological phosphorus removal, phosphorus removal

Procedia PDF Downloads 309
2131 Elucidating the Genetic Determinism of Seed Protein Plasticity in Response to the Environment Using Medicago truncatula

Authors: K. Cartelier, D. Aime, V. Vernoud, J. Buitink, J. M. Prosperi, K. Gallardo, C. Le Signor

Abstract:

Legumes can produce protein-rich seeds without nitrogen fertilizer through root symbiosis with nitrogen-fixing rhizobia. Rich in lysine, these proteins are used for human nutrition and animal feed. However, the instability of seed protein yield and quality due to environmental fluctuations limits the wider use of legumes such as pea. Breeding efforts are needed to optimize and stabilize seed nutritional value, which requires to identify the genetic determinism of seed protein plasticity in response to the environment. Towards this goal, we have studied the plasticity of protein content and composition of seeds from a collection of 200 Medicago truncatula ecotypes grown under four controlled conditions (optimal, drought, and winter/spring sowing). A quantitative analysis of one-dimensional protein profiles of these mature seeds was performed and plasticity indices were calculated from each abundant protein band. Genome-Wide Association Studies (GWAS) from these data identified major GWAS hotspots, from which a list of candidate genes was obtained. A Gene Ontology Enrichment Analysis revealed an over-representation of genes involved in several amino acid metabolic pathways. This led us to propose that environmental variations are likely to modulate amino acid balance, thus impacting seed protein composition. The selection of candidate genes for controlling the plasticity of seed protein composition was refined using transcriptomics data from developing Medicago truncatula seeds. The pea orthologs of key genes were identified for functional studies by mean of TILLING (Targeting Induced Local Lesions in Genomes) lines in this crop. We will present how this study highlighted mechanisms that could govern seed protein plasticity, providing new cues towards the stabilization of legume seed quality.

Keywords: GWAS, Medicago truncatula, plasticity, seed, storage proteins

Procedia PDF Downloads 128
2130 Health Promoting Properties of Phytochemicals from Rosemary (Rosmarinus officinalis) for Cancer and Inflammatory Bowel Disease

Authors: Jeremy J. Johnson

Abstract:

Mediterranean herbs including rosemary (Rosmarinus officinalis) contain a variety of phytochemicals including diterpenes that possess extensive biological activity. Applications of diterpenes, including the more abundant forms carnosol and carnosic acid, have been shown to possess anti-cancer, anti-inflammatory, anti-oxidant, and anti-proliferation properties. To confirm these properties, we have evaluated rosemary extract and selected diterpenes for biological activity in cancer and inflammatory models. Our preliminary data have revealed that select diterpenes can disrupt androgen receptor functionality in prostate and breast cancer cells. This property is unique among natural products for hormone-responsive cancers. The second area of interest has been evaluating rosemary extract and selected diterpenes for activation of sestrin-2, an antioxidant protein, in colon cancer cells. A combination of in vitro and in vivo approaches have been utilized to characterize the activity of rosemary diterpenes in rosemary. Taken together, these results suggest that phytochemicals found in rosemary have distinct pharmacological actions for disrupting cell-signaling pathways in cancer and inflammatory bowel disease.

Keywords: rosemary, diterpene, cancer, inflammation

Procedia PDF Downloads 133
2129 Nutritional Indices and Biology of the Armyworm, Spodoptera litura on Five Cotton Varieties

Authors: Md. Ruhul Amin

Abstract:

The effects of CB1, CB3, CB5, CB8 and CB12 cotton varieties on the nutritional indices and biological parameters of armyworm Spodoptera litura were studied under laboratory conditions. The armyworm larvae showed the highest and lowest food consumption rates on CB8 and CB1 variety, respectively. The efficiency of the conversion of digested food, efficiency of conversion of ingested food, approximate digestibility rates were statistically higher and similar on CB5 and CB8, and lowest on CB1. The larvae reared on CB12 variety exerted the lowest feeding and growth indices, and the relative growth rate was highest on CB8. The survival rates of egg, larva, pupa and adult moths were found highest on CB8 and lowest on CB12. The development durations of the immature stages of the insect differed significantly and the time elapsed from egg-to-adult emergence, longevity of both male and female moths, and their lifecycle were shortest on CB12 variety. The nutritional indices and biological parameters of the armyworm indicated that the varieties CB5 and CB8 were suitable host plants for feeding and development of S. litura.

Keywords: gossypium hirsutum, spodoptera litura, food consumption, life history

Procedia PDF Downloads 363
2128 Use of Giant Magneto Resistance Sensors to Detect Micron to Submicron Biologic Objects

Authors: Manon Giraud, Francois-Damien Delapierre, Guenaelle Jasmin-Lebras, Cecile Feraudet-Tarisse, Stephanie Simon, Claude Fermon

Abstract:

Early diagnosis or detection of harmful substances at low level is a growing field of high interest. The ideal test should be cheap, easy to use, quick, reliable, specific, and with very low detection limit. Combining the high specificity of antibodies-functionalized magnetic beads used to immune-capture biologic objects and the high sensitivity of a GMR-based sensors, it is possible to even detect these biologic objects one by one, such as a cancerous cell, a bacteria or a disease biomarker. The simplicity of the detection process makes its use possible even for untrained staff. Giant Magneto Resistance (GMR) is a recently discovered effect consisting in the electrical resistance modification of some conductive layers when exposed to a magnetic field. This effect allows the detection of very low variations of magnetic field (typically a few tens of nanoTesla). Magnetic nanobeads coated with antibodies targeting the analytes are mixed with a biological sample (blood, saliva) and incubated for 45 min. Then the mixture is injected in a very simple microfluidic chip and circulates above a GMR sensor that detects changes in the surrounding magnetic field. Magnetic particles do not create a field sufficient to be detected. Therefore, only the biological objects surrounded by several antibodies-functionalized magnetic beads (that have been captured by the complementary antigens) are detected when they move above the sensor. Proof of concept has been carried out on NS1 mouse cancerous cells diluted in PBS which have been bonded to magnetic 200nm particles. Signals were detected in cells-containing samples while none were recorded for negative controls. Binary response was hence assessed for this first biological model. The precise quantification of the analytes and its detection in highly diluted solution is the step now in progress.

Keywords: early diagnosis, giant magnetoresistance, lab-on-a-chip, submicron particle

Procedia PDF Downloads 239