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Nutritional Status of Red Amaranth as Influenced by Selected Pesticides  [PDF]
Md. Shariful Islam,Jahan Ara Khatoon,M. Alamgir,Md. Afzal Hossain
Pakistan Journal of Biological Sciences , 2003,
Abstract: A study was undertaken in the Department of Biochemistry, Bangladesh Agricultural University, Mymensingh to evaluate the nutritional status of red amaranth as influenced by three selected pesticides at various dose levels. The results revealed that the level of moisture content ranged from 86.50 to 87.62% in different treatment groups. The highest amount was in T4 where chlorpyrifos @ 0.66 a.i./ha was sprayed at 21 days after emergence and the lowest (86.5%) was in control group (T13) where no pesticide was applied. The dry matter percent was highest in control (13.50%) and slightly lower in treatment groups indicating no significant variation among them. The protein percent was from 5.02 to 5.24 in different treatment groups expressing little higher than the control plants (4.82%). Fat percentage ranged from 0.10 to 0.12 in treatment groups, which were very close to control value. Total sugar was highest (2.10) in T7, T9 and T11 and lowest in T6 (carbofuran). Reducing sugar was 1.15% in T7 (cypermethrin and chlorpyrifos) and 0.98 in T6, while non-reducing sugar seemed to be little higher (1.11%) in treatment groups compared to the control (0.88%). As a whole pesticide studied had very insignificant effect on protein, fat, ash, dry matter and moisture content of red amaranth. The carotene content was highest (10.24 mg 100 gG1) immediately after harvest in T1 and lowest in T8. But the level of carotene decreased to 9.08 mg 100 gG1 in T8, which was statistically insignificant. As far as vitamin C is concerned, the level was reasonably good in all the treatments as well as control plants immediately after harvest (38.52 mg - 40.41 mg). The level of vitamin C decreased in all the treatment and control plants after 20 minutes cooking (26.21-28.25 mg).
Development and validation of a multi-residue analytical methodology to determine the presence of selected pesticides in water through liquid chromatography
Brondi, Silvia H. G.;Lan?as, Fernando M.;
Journal of the Brazilian Chemical Society , 2005, DOI: 10.1590/S0103-50532005000400026
Abstract: in the present work an analytical methodology is described to determine the presence of multi-residues of selected pesticides used in sugar-cane cultures (tebuthiuron, hexazinone, diuron, 2,4-d and ametrine), in source of drinking water. the analytes were isolated from the water matrix through the following techniques: liquid-liquid extraction (lle) using dichloromethane as solvent; solid phase extraction (spe) using c18 as solid support and acetonitrile as solvent to condition the solid phase and elution of the analytes; and supercritical fluid extraction (sfe) using c18 as solid support and co2 in supercritical state as extractant solvent. the chromatographic analysis was done by high performance liquid chromatography (hplc) with an ultraviolet detector and using acetonitrile/water as mobile phase. among the three evaluated extraction techniques, the best results were obtained with both liquid-liquid extraction and solid phase extraction.
Monitoring of some pesticides residue in consumed tea in Tehran market  [cached]
Amirahmadi Maryam,Shoeibi Shahram,Abdollahi Mehdi,Rastegar Hossein
Iranian Journal of Environmental Health Science & Engineering , 2013, DOI: 10.1186/1735-2746-10-9
Abstract: Tea is an agricultural product of the leaves, leaf buds, and internodes of various cultivars and sub-varieties of the Camellia sinensis plant, processed and vulcanized using various methods. Tea is a main beverage in Iranian food basket so should be free from toxic elements such as pesticides residue. There is no data bank on the residue of pesticides in the consumed black tea in Iran. The present study is the first attempt for monitoring of 25 pesticide residues from different chemical groups in tea samples obtained from local markets in Tehran, I.R. Iran during the period 2011. A reliable and accurate method based on spiked calibration curve and QuEChERS sample preparation was developed for determination of pesticide residues in tea by gas chromatography–mass spectrometry (GC/MS). The using of spiked calibration standards for constructing the calibration curve substantially reduced adverse matrix-related effects and negative recovery affected by GCB on pesticides. The recovery of pesticides at 3 concentration levels (n = 3) was in range of 81.4 - 99.4%. The method was proved to be repeatable with RSDr lower than 20%. The limits of quantification for all pesticides were ≤20 ng/g. 53 samples from 17 imported and manufactured brand were analyzed. Detectable pesticides residues were found in 28.3% (15 samples) of the samples. All of the positive samples were contaminated with unregulated pesticides (Endosulfan Sulfate or Bifenthrin) which are established by ISIRI. None of the samples had contamination higher than maximum residue limit set by EU and India.
Monitoring of Some Pesticides Residue in Consumed tea in Tehran Market  [PDF]
Maryam Amirahmadi,Shahram Shoeibi,Mehdi Abdollahi,Hossein Rastegar
Iranian Journal of Environmental Health Science & Engineering , 2013,
Abstract: Tea is an agricultural product of the leaves, leaf buds, and internodes of various cultivars and sub-varieties of the Camellia sinensis plant, processed and vulcanized using various methods. Tea is a main beverage in Iranian food basket so should be free from toxic elements such as pesticides residue. There is no data bank on the residue of pesticides in the consumed black tea in Iran. The present study is the first attempt for monitoring of 25 pesticide residues from different chemical groups in tea samples obtained from local markets in Tehran, I.R. Iran during the period 2011. A reliable and accurate method based on spiked calibration curve and QuEChERS sample preparation was developed for determination of pesticide residues in tea by gas chromatography--mass spectrometry (GC/MS). The using of spiked calibration standards for constructing the calibration curve substantially reduced adverse matrix-related effects and negative recovery affected by GCB on pesticides. The recovery of pesticides at 3 concentration levels (n = 3) was in range of 81.4 - 99.4%. The method was proved to be repeatable with RSDr lower than 20%. The limits of quantification for all pesticides were <=20 ng/g. 53 samples from 17 imported and manufactured brand were analyzed. Detectable pesticides residues were found in 28.3% (15 samples) of the samples. All of the positive samples were contaminated with unregulated pesticides (Endosulfan Sulfate or Bifenthrin) which are established by ISIRI. None of the samples had contamination higher than maximum residue limit set by EU and India.
Performance of Red Amaranth under Shade Condition for Agroforestry Systems  [PDF]
M.A. Wadud,G.M.M. Rahman,M.J.U. Chowdhury,M.G. Mahboob
Journal of Biological Sciences , 2002,
Abstract: Performance of red amaranth (Amaranthus gangeticus) under four levels of light- 100, 75, 50, and 25% photosynthetically active radiation (PAR) was evaluated to judge its suitability for inclusion in agroforestry systems. Mosquito nets of different mesh size have been used to create desirable light levels. It was observed that in red amaranth, any reduction in PAR affected all morphological and yield parameters of red amaranth negatively. Plant height, number of leaves plant-1, leaf size, stem girth, fresh and dry yield were decreased significantly with decreasing light levels but the trend of response of different morphological parameters to different light levels were different. The mean fresh and dry yield (t ha-1) of red amaranth grown under 100, 75, 50 and 25 % PAR levels were 12.77, 9.54, 5.75, 3.19 and 1.27, 0.92, 0.55, 0.26, respectively. Therefore, red amaranth may not be included in tree-crop agroforestry system.
Determination of Pesticides Residues in Selected varieties of Mango  [PDF]
Saqib Hussain,Tariq Masud,Karam Ahad
Pakistan Journal of Nutrition , 2002,
Abstract: The present study was undertaken to access the residue of commonly used pesticides viz Cypermethrin, Methamedophos, Monocrotophos, Cyfluthrin, Dialdrin and Methyl Parathian respectively in three varieties of Mango being collected from the grower fields in Multan division. The samples were treated with organic solvent Cyclohexane and ethylacetate (1:1), cleaned on Gel Permeation Chromatograph (GPC) and analyzed on auto system Gas Chromatograph (GC) with electron capture detector (ECD). All the samples were found to be contaminated with a degree of variation of pesticides residue studied. However, all the samples were within permissible limits being set by FAO/WHO with reference to public health.
Determination of Organophosphorous and Carbamat Pesticides Residue in Drinking Water Resources of Hamadan in 2007
M Khodadadi,M.T Samadi,A.R Rahmani,R Maleki
Iranian Journal of Health and Environment , 2010,
Abstract: "n "nBackgrounds and Objectives: Water contamination by pesticides is considered as an environmentalproblem today. In terms of agricultural development and diversity of plant pests, the use of pesticides has been increasing. Hamedan province has a suitable agricultural condition, it has enjoyed significant development in this respect. Among all the cities of Hamedan province, Hamedan city has the highest rank in tiller crops. Therefore, yearly use of pesticides is increasing in this area; which could be a serious threat to water resources of the city. The aim of this survey was determinaton of Organophosphorous and Carbamat pesticides residue in drinking water resources of Hamadan in 2007."nMaterials and Methods: In this survey, 126 water samples were collected from 7 drinking water resources of Hamedan during 12 consecutive months in 2007. for determination of these pesticides,two methods (solid- phase extraction and Liquid-Liquid extraction) were adopted .and samples were analyzed by means of HPLC and GC/MS applying standard methods."nResults: Final results showed that the most concentration of Chlorpyrifos and Carbaryl pesticides were found to be about 3.85 ppb (part per billion) and 1.8 ppb in spring and June respectively; the maximum concentration of Diazinon was about 36.5ppb in October (autumn).The minimum concentration of the three pesticides was detected in winter. According to the statistical test Two - Way ANOWA there were significant differences among pesticides concentrations in the water samples in different seasons (p<0.05) . However, there wasn't a significant difference in pesticides concentrations in surface and ground water samples(p>0.05). "nConclusion: Different studies have shown that pesticides residue concentration in water samples have a relationship with the amount of pesticides used in an area, physical and chemical refractory properties of pesticides; and environmental conditions. Thus, using resistant pollutants such as pesticides will be a serious threat to health of water consumers if they are not properly controlled.
Growth and Harvestable Maturity of Red Amaranth at Different Sowing Dates  [PDF]
S.R. Saha,M. Nazim Uddin,M.A. Rahman,S.M. Sharifuzzaman
Asian Journal of Plant Sciences , 2003,
Abstract: A study was conducted to optimize the time of sowing and stage of harvest of red amaranth during winter season to obtain higher yield without loss of palatability. It was observed that in November sowing, highest palatability (1.59) was achieved when harvested at 15 DAS. Harvesting at 20 days after sowing (DAS) was found to be suitable for November sowing considering economic yield as well as palatability. In December sowing had moderate palatability with leaf-stem ration 1.38. On the other hand, in January sowing when harvested at 30 DAS expressed acceptable leaf-stem ration (1.71). Therefore, considering yield and optimum palatability, harvesting of the crop should be done at 25 DAS in December sowing and 30 DAS in January sowing.
Kinetic and Thermodynamic Study for Fenton-Like Oxidation of Amaranth Red Dye  [PDF]
Z. M. Abou-Gamra
Advances in Chemical Engineering and Science (ACES) , 2014, DOI: 10.4236/aces.2014.43031
Abstract:

Oxidation by Fenton like reactions (Fe3+/H2O2) is economically process for destructive hazardous pollutants in waste water. The effects of different parameters such as, amaranth red dye, ferric chloride, hydrogen peroxide concentrations, pH value of solution, temperature and the presence of inorganic ions (carbonate, nitrate, chloride) on oxidative decolorization of amaranth were investigated. Amaranth degradation by (Fe3+/H2O2) reagent was found to follow first order kinetic model. Under optimum condition, pH = 2.6 and [FeCl3] = 3.75 × 10-4 mol·dm-3, the amaranth in aqueous solution with an initial concentration of 5 × 10-5 mol·dm-3 was degraded by 95% within 6 minutes. Increasing temperature in the range of 298 - 308 K increases the rate of dye degradation. Thermodynamic constants, ΔH*, ΔS* and ΔG* were evaluated. The results implied that the oxidation process was favorable and endothermic.

Interference of Selected Palmer Amaranth (Amaranthus palmeri) Biotypes in Soybean (Glycine max)  [PDF]
Aman Chandi,David L. Jordan,Alan C. York,Susana R. Milla-Lewis,James D. Burton,A. Stanley Culpepper,Jared R. Whitaker
International Journal of Agronomy , 2012, DOI: 10.1155/2012/168267
Abstract: Palmer amaranth (Amaranthus palmeri S. Wats.) has become difficult to control in row crops due to selection for biotypes that are no longer controlled by acetolactate synthase inhibiting herbicides and/or glyphosate. Early season interference in soybean [Glycine max (L.) Merr.] for 40 days after emergence by three glyphosate-resistant (GR) and three glyphosate-susceptible (GS) Palmer amaranth biotypes from Georgia and North Carolina was compared in the greenhouse. A field experiment over 2 years compared season-long interference of these biotypes in soybean. The six Palmer amaranth biotypes reduced soybean height similarly in the greenhouse but did not affect soybean height in the field. Reduction in soybean fresh weight and dry weight in the greenhouse; and soybean yield in the field varied by Palmer amaranth biotypes. Soybean yield was reduced 21% by Palmer amaranth at the established field density of 0.37 plant m?2. When Palmer amaranth biotypes were grouped by response to glyphosate, the GS group reduced fresh weight, dry weight, and yield of soybean more than the GR group. The results indicate a possible small competitive disadvantage associated with glyphosate resistance, but observed differences among biotypes might also be associated with characteristics within and among biotypes other than glyphosate resistance. 1. Introduction Palmer amaranth is one of the most troublesome weeds of agronomic crops in the southeastern United States [1–3] because of its competitive ability, C4 photosynthesis, higher water use efficiency, and rapid growth rate [4, 5]. This weed also possesses drought tolerance mechanisms which allow survival under limited water availability [6–8] and it adapts readily to shading [9]. Several biotypes of Palmer amaranth have evolved resistance to herbicides representing different modes of action, including 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) inhibitors, mitotic inhibitors, acetolactate synthase (ALS) inhibitors, and photosynthetic inhibitors [10], which make it challenging to control in cropping systems. Species, density, and time of emergence with respect to the crop determine the relative competitiveness of pigweed species [11–14]. Interference of pigweed species including common waterhemp (Amaranthus rudis Sauer) [15–17], Palmer amaranth [11, 17, 18], and redroot pigweed (Amaranthus retroflexus L.) [14, 17, 19–22] has been evaluated in soybean. Soybean yield reduction as a result of interference increased from 17% to 68% with an increase in Palmer amaranth density from 0.33 to 10 plants m?1 of row length [11].
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