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Effect of organic amendment on organic metabolites in root knot nematode (Meloidogyne Incognita) infested spinach
2017
Gupta, Shalini
The Nematodes are roundworms that are found in every environment of the earth. While some species are harmful parasites, others play a vital role in nutrient cycle and medical research. Nematode infestation in the fields is poly-specific; however, depending on the agro-climatic conditions, one or two species are dominant over the rest. The present studies attempts to observe and control the root knot infestation on spinach (Spinacea oleracea), which belong to Chenopodiaceous family and is extensively cultivated in India for its nutritious leaves. Various organic metabolites have been estimated in root knot nematode infested spinach, including chlorophyll, total carbohydrates, and total free amino acids. Spinach plants, infested with root knot nematode, have been treated with peels of lemon, which proved beneficial in terms of increased chlorophyll content. Altered total carbohydrate and total free amino acid content have been found with S/4 of lemon-peel-treated spinach plants. It has been found that the infested spinach shows 137.5% carbohydrate content over the normal plants. The kaghzi neemboo amended spinach contains lower carbohydrate than normal-control. Rate of carbohydrate contents has been found to be inversely proportional to the rate of extracts concentrations as S/4, S/2, and S show 92.5%, 55%, and 37.5% increase over normal-control spinach. The bio-amendment of citrus aurantifolia, (kaghzi neemboo) helps controlling root knot nematodes, which is more beneficial than using chemicals to control the same, as the chemical fertilizer causes pollution, exerting negative impacts on flora and fauna.
显示更多 [+] 显示较少 [-]Provisional Evaluation of Composting as Priority Option for Sustainable Waste Management in South-West Nigeria
2017
Olukanni, David | Aremu, Damilola
The management of Municipal Solid Waste (MSW) in Nigeria and most developing countries has remained a major public health challenge, thus creating the need for reliable and environmentally-acceptable alternatives. This study focuses on composting assessment as a viable recovery alternative for MSW in six States of Southwest Nigeria, namely: Ekiti, Osun, Ondo, Ogun, Oyo, and Lagos. Extensive literature review has been carried out to understand the waste generation patterns in these states. Reported literature data has been assessed for sustainability of composting strategy in terms of organic waste streams, amenable of biotransformation as well as in terms of return through energy saving and material recovery. A life-cycle framework has been used to estimate GHG emissions, available nutrients, and potential compost production, instead of landfill in each region. Results show significant potential compost production of 895,659-, 255,267-, 153,423-, 117,468-, 113,094- and 112, 397-m3/yr for Lagos, Oyo, Ogun, Osun, Ondo, and Ekiti, respectively. It has been deduced from the study that composting would be very beneficial to the economy as its product would boost agriculture production while reducing the budget spent on fertilizer annually.
显示更多 [+] 显示较少 [-]Phytoremediation potential of heavy metals by two native pasture plants (Eucalyptus grandis and ailanthus altissima) assisted with AMF and fibrous minerals in contaminated mining regions
2017
Abbaslou, Hakime | Bakhtiari, Somayeh
The current study assesses the effect of fibrous clay minerals’ amendments and arbuscular mycorrhiza incubation on heavy metal uptake and translocation in Eucalyptus grandis and Ailanthus altissima plants. For doing so, Eucalyptus and ailanthus trees have been grown in a soil sample, contaminated with heavy metal iron ore mining and collected from southern Iran. The area under study is arid, with the majority of trees being ailanthus and eucalyptus. Amounts of Cd, Pb, Zn, Cu, and Mn have initially been at toxic levels which declined after cultivation. Fibrous clay minerals have been added to soils as a natural adsorbent to adsorb heavy metals like Pb, Cd, Zn, and Mn. Accumulation of the elements in the roots and shoots has been in the following order: Cu>Zn>Mn>Cd>Pb>Fe. The organ metal concentrations have not statistically translocated from roots to shoots of plants, except for Zn and Cu whose concentrations have been significantly higher in roots. Eucalyptus is well capable of extracting elements from contaminated soils, compared to ailanthus, particularly in case of Cu and Cd. The percentage of mycorrhizal colonization proves to be more in pots with ailanthus plants grown in contaminated soil, suggesting enhanced effect of high metal concentrations on plant infection by G. mosseae. AMF assists soil remediation by enhancing the growth and retention of toxic elements by ailanthus, while no substantial change has been observed between inoculated and non-inoculated eucalyptus plants by AFM, regarding translocation of elements to plants. The possibility of increasing metal accumulation in roots is interesting for phytoremediation purposes, since most high-producing biomass plants, such as eucalyptus, retain heavy metals in roots.
显示更多 [+] 显示较少 [-]Status of CO as an air pollutant and its prediction, using meteorological parameters in Esfahan, Iran
2017
Masoudi, Masoud | Gerami, Soraya
The present study analyzes air quality for Carbon monoxide (CO), in Esfahan with the measurements taken in three different locations to prepare average data in the city. The average concentrations have been measured every 24 hours, every month and every season with the results showing that the highest concentration of CO occurs generally in the morning and at the beginning of night, while the least concentration has been found in the afternoon and early morning. Monthly concentrations of CO show the highest values in August and the lowest values in February. The seasonal concentrations show the least amounts in spring, while the highest amounts belong to summer. Relations between the air pollutant and some meteorological parameters have been calculated statistically, using the daily average data. The data include Temperature (min, max), precipitation, Wind Direction (max), Wind Speed (max), and Evaporation, considered independent variables. The relations between the pollutant concentration and meteorological parameters have been expressed by multiple linear regression equations for both annual and seasonal conditions, using SPSS software. Analysis of variance shows that both regressions of ‘enter’ and ‘stepwise’ methods are highly significant, indicating a significant relation between the CO and different variables, especially for temperature and wind speed in annual condition. RMSE test shows that among different prediction models, stepwise model is the best option.
显示更多 [+] 显示较少 [-]Removal of caffeine from aqueous solution using multi-wall carbon nanotubes: kinetic, isotherm, and thermodynamics studies
2017
Bahrami, Mehdi | Amiri, Mohammad Javad | Koochaki, Sara
The occurrence of contaminants in wastewaters, and their behavior during wastewater treatment and production of drinking water are key issues to re-use water resources. The present research aims to remove caffeine from aqueous solutions via adsorption technique, using Multi-Wall Carbon Nanotubes (MWCNTs) as an adsorbent under different experimental conditions. The processing variables such as pH (2-12), contact time (1-30 min), initial concentration of caffeine (2-314 mg/L), temperature (25, 50, 80 °C), and adsorbent mass (0.02-0.15 g) have been investigated with equilibrium and kinetic studies on adsorption of caffeine onto MWCNTs being also developed. Maximum caffeine removal has been obtained at pH=7 and adsorption equilibrium has been achieved in 5 min. The use of pseudo second-order kinetic model with determination coefficient of 99.3% (R2=0.993), has made the adsorption kinetics to be well fitted. The caffeine equilibrium adsorption data have been best fitted to Langmuir-Freundlich Model with a relatively high determination coefficient of 96.5% (R2=0.965) and maximum adsorption capacity of 35.61 mg/g of caffeine on MWCNTs. The thermodynamic parameters display that the adsorption of caffeine onto MWCNTs has been non-spontaneous and endothermic in nature.
显示更多 [+] 显示较少 [-]Investigating the effects of plant growth promoting bacteria and Glomus Mosseae on cadmium phytoremediation by Eucalyptus camaldulensis L.
2017
Motesharezadeh, Babak | kamal-poor, Sama | Alikhani, Hossein Ali | Zariee, Mehdi | Azimi, Sina
This research aims to study the effect of Mycorrizal fungus and Plant-Growth-Promoting Bacteria (PGPB) on Cadmium (Cd) uptake by one-year-old Eucalyptus Camaldulensis seedlings. The treatments have involved three levels of heavy metal (0, 30, and 60 mg/kg) for Cd, and three bacterial levels (no bacteria (B0), Bacillus (Ba105), and Pseudomonas (Ps36, Ps448)), inoculated with mycorrhizal fungus Glomus mosseae (M1) and non-inoculated with fungus (M0). Results show that absorption of these elements in plant increased as Cd concentration in soil became more. Inoculation by Ps448 bacteria had an incremental effect on Cd uptake by 90%, compared to the non-inoculated (control) samples. Moreover, inoculation of the plants with mycorrhizal fungus increased Cd uptake by 24%, compared to the control. Also, it has been observed that plant resistance to metal stress and plant growth under such conditions ascended in treatments wherein inoculation happened with mycorrhizal fungus and bacteria. The highest Cd heavy metal uptake has been observed in Eucalyptus (shoots and roots), treatment (C2B2M1) with 648.19 micrograms per one seedling in pot. According to the obtained results, Eucalyptus with biological factors (fungi and bacteria) has the ability to clean and purify the contaminated soil with Cd heavy metal.
显示更多 [+] 显示较少 [-]Acute toxicity of povidone-iodine (Betadine) in common carp (Cyprinus carpio L. 1758)
2017
Forouhar Vajargah, Mohammad | Mohammadi Yalsuyi, Ahmad | Hedayati, Aliakbar
Organisms in aquatic environments are exposed to a number of pollutants such as pharmaceutical residues. As such, the aim of the present study is to achieve the Lethal Concentration (LC50) of Povidone-iodine (Betadine) for Cyprinus carpio. To do so, the study employs samples, weighing 4±1 [mean±SD] gr, and carries out an experiment in static condition. Based on OECD instructions, after a period of 4 days under controlled water, the physicochemical factors give the following results: pH= 8-8.3, BOD= 690 mg/l, total hardness= 210 mg, and CaCo3 and temperature= 17±0.1 °C. All fish are acclimatized for 10 days in an aquarium, 60×55×30 cm in size, which included the control group (no toxic concentration) as well as the treated aquariums, with Betadine concentration of 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 400, and 600 mg/l. LC10, LC20, LC30, LC40, LC50, LC60, LC70, LC80, LC90, and LC95 have been measured for 6, 12, 18, and 24 hours. LC50 24h Betadine for C. carpio has been 158.273 ml/l, showing no mortality after 24 hours (i.e. 48h, 72h, and 96h). Results of the present study suggest that Betadine is practically nontoxic and not irritant at low concentrations for this species and it has a short half-life in aquatic environments.
显示更多 [+] 显示较少 [-]Biochemical characterization of recombinant benzyl alcohol dehydrogenase from Rhodococcus ruber UKMP-5M
2017
Tavakoli, Arezoo | Hamzah, Ainon
Benzyl Alcohol Dehydrogenase (BADH) is an important enzyme for hydrocarbon degradation, which can oxidize benzyl alcohols to aldehydes, while being capable of catalyzing a reversible reaction by reducing benzaldehyde. BADH is a member of medium chain alcohol dehydrogenases, in which zinc and NAD are essential for enzyme activity. This paper describes the expression, purification, and characterization of recombinant benzyl alcohol dehydrogenase, encoded by xylB gene from Rhodococcus ruber UKMP-5M. The gene has been amplified and cloned into E. coli, and the recombinant plasmid pGEMT-xylB has been digested by NdeI and HindIII to construct plasmid pET28b-xylC and then ligated into E. coli BL21 (DE3), itself induced by 0.3 mM isopropyl β-D-thiogalactoside (IPTG) at 25°C. The expressed BADH has been 38 kDa, and is purified by affinity chromatography, in which the specific activity was 30 U/mg after 17 folds purification, leading to a NAD-dependent enzyme that uses benzyl alcohol as a substrate for enzyme characterization. The final metabolite is benzaldehyde, identified by gas chromatography mass spectrometry (GC-MS). The BADH activity has been 0.7 U/mL and the optimum pH and temperature, 9.5 and 30ºC, respectively. Also the Michaelis constant (Km) and maximum velocity (Vmax) have accounted to 705 µM and 1.3 U/mL, respectively. Benzyl alcohol dehydrogenase from R. ruber UKMP-5M can be used for hydrocarbon biodegradation in contaminated sites.
显示更多 [+] 显示较少 [-]Microbio-ecology and hydro-geochemistry of saline sulfur springs of Ghale-Madreseh, Khuzestan, Iran
2017
Papizadeh, Moslem | Roayaei Ardakani, Mohammad | Fakour, Hossein | Ghaderi, Golgol | Firouzei, Yavar
Ghale-madreseh is the first point that the saline and sulfurous streams flow into Tembi River, one of the well-known saline rivers in Khuzestan province, Iran. This river is one of the main sources of increasing Karun River’s salinity, which is the largest river in Iran in terms of discharge. There are three saline and sulfurous springs (Shour-1, Shour-2m and Namak Springs) as well as a drinkable one (Shireen spring) in Ghale-madreseh region. Normally, most probable number counting of sulfate reducing, sulfur oxidizing and nitrate reducing bacteria showed that there are different patterns of microbial populations in the springs of Ghale-madreseh region. The observed differences are highly attributed to the hydro-geochemical properties of the springs. It is assumed that the groundwater which streams in the Gachsaran formation receives considerable amounts of SO42- (0.09-0.1 M), Na+ (1.654-3.604 M), and Cl- (1-548-3.775 M) by halite and gypsum dissolution, resulting in the saline and sulfurous springs on the Gachsaran formation. Also, due to the low depth of local oil reservoirs, activity of sulfate reducing bacteria in the close vicinity of oil reservoirs and groundwater streams is highly probable. Hence, the microbial sulfate reduction may be responsible for the production of H2S, probably playing a role in the souring of local oil reservoirs. Besides, the groundwater that reaches the Bakhtiary formation shows different characteristics as detected in Shireen spring.
显示更多 [+] 显示较少 [-]Evaluation Euro IV of effectiveness in transportation systems of Tehran on air quality: Application of IVE model
2017
Ghadiri, Zahra | Rashidi, Yousef | Broomandi, Parya
The quick growth of vehicles is due to fast urbanization in mega cities during last decades. This phenomenon has serious impacts on air quality, as emission from mobile vehicles is the major source of air pollution. As a result, any attempt to reduce the emitted air pollutants is needed. This study aims at improving the fuel quality in transporting system with particular emphasis on taxis in Tehran in 2014. As a clean fuel, Euro IV is being used to reduce the emission of pollution, toxic substances, and greenhouse gases. A bottom-up approach to evaluate vehicular emission, using IVE (International Vehicle Emission) model in Tehran, has been presented, which employs the local vehicle technology and its distributions, vehicle soak distributions, power based driving factors, and meteorological parameters to evaluate the emission, itself. Results show that the most abundant air pollutant (CO) has been reduced by 87.6% due to the clean fuel consumption (Euro IV). Also, the emission rates of the predominant toxic pollutant (Benzene) decreased by 98.7%. As a clean fuel, Euro IV managed to increase the emitted amount of CO2 and NH3. It can be concluded that upgrading transportation system with updated fuel quality is an essential step to improve air quality in Tehran.
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