Hasan Izanloo; Seyyed Mostafa Khezri; Gharib Majidi; Aliasghar Al Sheykh; Hamidreza Tashauoei; Mohammad Khazaee; Behnam Vakili; Vahid Vaziri rad; Hossein Aghababaee; Shahnaz Arsang Jang
Volume 21, Issue 6 , January and February 2015, , Pages 1194-1204
Abstract
Background: The purpose of this study was surveying the trends of nitrate variations in drinking water of rural areas of Qom province and its mapping using GIS software.
Materials and Methods: This study was of descriptive cross-sectional type. The collected data related to nitrate concentrations during ...
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Background: The purpose of this study was surveying the trends of nitrate variations in drinking water of rural areas of Qom province and its mapping using GIS software.
Materials and Methods: This study was of descriptive cross-sectional type. The collected data related to nitrate concentrations during years 2006-2011 were acquired from Qom Province Rural Water and Wastewater Company. During the year 2012, 73 wells were tested via two sampling runs; one sampling set performed in wet season and the other one carried out in the dry season. Nitrate concentrations were determined spectrophotometric ally. The Chi-squared test and segmented regression model were used for data analysis. Four software’s, namely, Excel-2007, SPSS-16 and Joinpoint-4.1, were used for data mapping and analysis.
Results: The average nitrate concentration during 2006-2012 period was 23.12 mg/L with the standard deviation of 18.68 mg/L. 7.5% and 4.9% of the surveyed wells were “at risk” and “contaminated”, respectively. Regression results indicated a lack of sufficient statistical evidence to accept an increasing trend of nitrate during the study period (P value=0.85). There was no significant difference in the contamination averages between the results of two sample sets which were taken during each year. During the beginning of 2006 to the beginning of 2013, an increasing trend of nitrate concentration was observed in the contaminated wells.
Conclusion: In the majority of monitored wells, the nitrate concentration was in the standard range. In the “at risk” wells and also in the others, the concentrations were beyond the standard levels. Therefore, Management approaches should be applied to avoid the nitrate penetration into the aquifers.
Behnam Vakili; Vahid Vazirirad; Hoseein Aghababaee; Gharib Majidi; Shahram Nazari; Mohammad Khazaee; Hamidreza Tashyiee; Mohammad Ahmamado Jabali; Hasan Izanlou
Volume 21, Issue 5 , September and October 2014, , Pages 925-933
Abstract
Background: This laboratory experiment was aimed of to investigate the antibacterial effect of Polypropylenimine-G2 (PPI-G2) and Polyamidoamine-G4 (PAMAM-G4) dendrimers on Klebsiella oxytoca, Pseudomonas aeruginosa and Proteus mirabilis.
Materials and Methods: Different concentrations of PPI-G2 and ...
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Background: This laboratory experiment was aimed of to investigate the antibacterial effect of Polypropylenimine-G2 (PPI-G2) and Polyamidoamine-G4 (PAMAM-G4) dendrimers on Klebsiella oxytoca, Pseudomonas aeruginosa and Proteus mirabilis.
Materials and Methods: Different concentrations of PPI-G2 and PAMAM-G4 dendrimers were inoculated onto Blank disks and were placed in Mueller-Hinton agar media. Zone of inhibition was investigated by bacterial inoculation according to the McFarland standard 0.5. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of PPI-G2 and PAMAM-G4 dendrimers were determined by Micro-dilution method in nutrient broth culture.
Results: Zone of inhibition in concentration 500 μg/ml of PPI-G2 dendrimers for Klebsiella oxytoca, Proteus mirabilis and Pseudomonas aeruginosa were 25, 15 and 20mm, respectively. Zone of inhibition in concentration 500 μg/ml of PAMAM-G4 dendrimers for Klebsiella oxytoca, Proteus mirabilis and Pseudomonas aeruginosa were 20, 18 and 0mm, respectively. The MIC of PPI-G2 dendrimer for Klebsiella oxytoca and for Pseudomonas aeruginosa were 5 μg/ml. Also, the MIC of PPI-G2 dendrimer for Proteus mirabilis was 50 μg/ml. The MBC of PPI-G2 dendrimer for Klebsiella oxytoca was 50 μg/ml and it was 500 μg/ml for Proteus mirabilis and Pseudomonas aeruginosa. The MIC of PAMAM-G4 dendrimer attributed to Klebsiella oxytoca and Proteus mirabilis were reported 500 and 1250 μg/ml, respectively. The MBC of PAMAM-G4 dendrimer belonged to Klebsiella oxytoca and Proteus mirabilis were 1250 and 2500 μg/ml, respectively.
Conclusion: According to the results, PPI-G2 dendrimers can eliminate Pseudomonas aeruginosa, Klebsiella oxytoca and Proteus mirabilis effectively but PAMAM-G4 only has antibacterial effect against Klebsiella oxytoca and Proteus mirabilis. Also the antibacterial activity of PPI-G2 dendrimer is obviously better than those of PAMAM-G4. However, using dendrimers can be considered as a new approach for drinking water disinfection but it requires further wide range studies.