فهرست مطالب

  • Volume:17 Issue:1, 2019
  • تاریخ انتشار: 1397/12/10
  • تعداد عناوین: 8
  • K Alijanipoor, R Hajihosseini, A Vaziri, Reyhaneh Sariri* Pages 1-9
    The proper consumption of plant wastes could not only provide a possible source of natural products, but it also is an environmental friendly research. The aim of this study was to use grape wastes as a source of peroxidase.  In practice, one isoenzyme of peroxidase (POD1) was partially purified from Vitis vinifera wastes, the plant which is widely harvested in Iran. The activity of this novel peroxidase was determined using guaiacol as its substrate. The new peroxidase was partially purified and its kinetic parameters determined. The values of Km and Vmax of peroxidase for guaiacol were 83.2 mM and 0.35 M/min respectively. Optimum pH and temperature were determined for guaiacol to be 6.2 and 60°C respectively. According to SDS-PAGE results, the molecular weight of isozymes was 38-40 KD. The results indicate that agricultural leftovers from Vitis vinifera are a considerable source for a peroxidase with reliable kinetic behaviors.
    Keywords: Vitis vinifera, plant wastes, peroxidase, kinetic parameter, guaiacol
  • Z Ceylan, H Dane, Ş Adil, Turgay Sisman* Pages 11-22
    The existence of toxicants in ecosystems has been increased dramatically in recent years, especially in aquatic environments. Phenols and chlorinated phenol derivatives are toxic industrial compounds. Phenols and derivatives are known to be environmental contaminants. In the present study, 2,4-Dichlorophenol, 2-Chlorophenol and substituted phenol were tested for embryotoxicity and mortality in a four-day period using zebrafish, Danio rerio embryos. Tested phenol derivatives caused teratogenicity and embryo mortality in the embryos. The semi static 48-h LC50 (median lethal concentration) value for Substituted-phenol was 13.850 mg L-1; the corresponding values for 2-Chlorophenol and 2,4-Dichlorophenol were 8.378 mg L-1 and 6.558 mg L-1, respectively. The endpoints are incomplete eyes, head and tail, heart and chorda deformity, yolk sac edema, tail curvature, shrunken eyes, lordosis, delayed hatching, weak pigmentation, heart edema and non-pigmentation after exposure to the compounds. 2,4-Dichlorophenol was found to be more toxic than the others. This paper is the first to describe the relative toxicity of a suite of phenols in the early life stages of zebrafish.
    Keywords: Substituted phenol, 2-Chlorophenol, 4-Dichlorophenol, zebrafish, embryotoxicity
  • M Rafiee, A Eslami, R Saeedi, M Abtahi, Mahsa Jahangiri Rad* Pages 23-41
    Although economic growth from industrialization has improved health and quality of life indicators, however, it has intensified the release of chemicals into the environment, with severe effects on health. The present work confers toxic metals contamination levels of surface waters in Zanjan Province, Iran, encompassing several rich mines of lead and zinc. The soluble concentrations of Fe, Cu, Cd, Ni, Pb, Zn and AS in water samples were determined using ICP-MS and the level of contamination was appraised by heavy metal pollution index (HPI). Multivariate statistical methods comprising Pearson’s correlation analysis, hierarchical cluster analysis, and principal component analysis were applied to evaluate the relationships between heavy metals. Geostatistical analyses were carried out to conduct the distribution characteristics and the sources of pollution. The results showed that concentrations of studied heavy metals were higher in the spring compared to the winter, however, the calculated HPI values did not exceed the limit of 15. Anthropogenic activities, for the most part, control the quality of water in this study area with minor natural/geogenic input. All the measured heavy metals were strongly homologous in spring based on correlation coefficients. However, this correlation gets weaker in the winter due to a degree of heterogeneity between Zn, Cd, As and other elements. Distribution pattern of the heavy metals pollution index of surface waters with different land uses decreased in the order of: agricultural>dry farming/water bodies>built up areas>forest areas. Multi hotspots for the above mentioned heavy metals were located in the southeast study areas.
    Keywords: Water quality, Heavy metal pollution index, Geostatistics, Spatial distribution
  • A.R Riyahi Bakhtiari, A Esmaili Sari, F Rahbarizadeh, N Hassanzadeh, Samar Mortazavi* Pages 43-53
    The aim of this study was to examine some potential effects of 4-Nonylphenol (4-NP), Bisphenol A (BPA), and mixture of them on common carp, Cyprinus carpio and demonstrate induction of vitellogenin (Vtg) as a biomarker for screening aquatic ecosystems. These compounds with other estrogenic chemicals may be responsible for disrupting effects observed in fish. A total of 100 juvenile carp were treated experimentally with 17β-estradiol (E2), and increasing doses of 4-NP, BPA and also mixture of them. Then the plasma Vtg levels were measured using indirect competitive ELISA. Results showed a significant (P<0.05) increase in Vtg levels of exposed carps with E2, maximum 4-NP, BPA and their mixture. The group treated with E2 showed high induction (490%) with respect to controls. The groups treated with maximum dose of 4-NP and BPA showed also induction of Vtg, whereas the group treated with their mixture (3 mg kg−1 b.w. 4-NP and 0.01 mg kg−1 b.w. BPA) showed the highest induction (2126%). Finally, results showed that mixture of 4-NP and BPA exhibited stronger (synergistic) effects. So that, large scale monitoring of estrogenic effects caused by contamination may be considered as a biomarker in urban and industrial effluents.
    Keywords: Vitellogenin (Vtg), Cyprinus carpio, 17β-Esteradiol (E2), 4-Nonylphenol (4-NP), Bisphenol A (BPA), ELISA
  • S Mohammadzadeh Baran, I Sharifpour, S Jamili, P Ghavam Mostafavi, Ali Mashinchian Moradi* Pages 55-62
    Methyl Tert-Butyl Ether(MTBE) increases oxygen consumption and reduces carbon monoxide and also air pollution. It is very active in soil, and its motility in water is a function of water movement in soil. MTBE is resistant to biodegradation, with high half-life and solubility in water and weak absorption in soil particles. The activities of SOD and CAT enzymes were examined in Rutilus caspicus in concentrations of 50, 100 and 150 mg L-1 MTBE for 7, 14 and 21 days. The mean water temperature and oxygen were 191°C and 7.60.2 respectively and salinity was maintained zero. 156 R. caspicus were stocked in aquariums, 3 specimens were randomly selected from aquarium in the first, second and third weeks. Blood serum was separated to assay the SOD and CAT activities. A strong significant positive relationship was found between MTBE concentration and SOD as well as CAT: [r(108)=0.73, P < 0.01]. Elevated MTBE increased the activity of SOD and CAT. In addition, there was a mean significant positive relationship between exposure time and SOD: [r(108)=0.41, P < 0.01]. SOD activity increased over time, and there was a negative weak significant relationship between exposure time and CAT [r(108)=-0.20, P < 0.05]. CAT activity decreased by prolonged exposure time. Moreover, there was a mean positive significant relationship between SOD and CAT [r(108)=0.41, P < 0.01].
    Keywords: Methyl tert-butyl ether (MTBE), Rutilus caspicus, antioxidant enzymes, superoxide dismutase (SOD), catalase (CAT)
  • Majid Ashouri* Pages 63-71
    Application of chemical fertilizers, especially urea, causes groundwater pollution. Therefore, to decrease environmental pollution, biological fertilizers may be employed. In order to investigate the effect of irrigation levels, Azospirillum and nitrogen levels on rice yield and its components, an experiment was conducted in the north of Iran during the crop season in 2013. The experiment was arranged in a split-split plot based on a completely randomized block design with 3 replications in which irrigation level was the main factor. The levels of factors used were: I1= continuous submergence and I2 = 11 days’ irrigation interval; A1 = application and A2= no application of Azospirillum as the sub factor; and nitrogen fertilizer levels as a sub-sub factor includingN1 = 0, N2 = 30, N3 = 60 and N4 = 90 kg ha-1. Continuous submergence and 11 days’ irrigation interval produced 4247 and 2720 kg ha-1, while the application of Azospirillum and the treatment without it produced 4064 and 2903 kg ha-1, respectively. Moreover, N4, N3, N2 and N1 produced 3950, 3800, 3225 and 2700 kg ha-1, while I1A1N4 and I1A1N3 had maximum and I2A2N1 had minimum mean values with 5381, 5330 and 1882 kg ha-1, respectively. Therefore, it is concluded that the application of a balanced nitrogen fertilizer with Azospirillum could prevent the indiscriminate use of chemical fertilizers and reduce nitrate pollution, leading towards more sustainable agriculture in the north of Iran.
    Keywords: biological fertilizer, nitrate pollution, paddy fields, rice
  • A Gholoubi, A Alizadeh, R Azadi, Hojat Emami* Pages 73-81
    The objective of this study was to investigate the effects of land use change on soil properties in six different sites of Guilan Province, Northern Iran.  The study sites were deforested approximately 40 years ago and changed to tea farms. Soil samples from 0 to 30 cm depth were collected in June 2016 and analyzed for total nitrogen (N), soil organic C (OC), available phosphorus, pH, electrical conductivity (EC), exchangeable Ca, Mg, Na, K, and Al, mean weight diameter (MWD) of aggregates, water stable aggregates (WSA) and bulk density. Soil properties of two soil land uses were compared. The results showed that after land use change from natural forest to tea farms, soil physical and chemical characteristics were changed. Land use change resulted in significant decreases in organic carbon, available potassium and pH. Reduction of annual organic matter input to soil as a result of deforestation and also rapid oxidation of organic matter in deforested places were responsible for a significant decrease in OC. Soil microbial respiration (SMR) also decreased significantly, following deforestation and decreasing the organic carbon. Changes in soil exchangeable Ca, Mg and available P in two land uses were not significant. The results indicated that tea farming for 40 years did not affect soil structural indicators (BD, MWD and WSA). Also decreasing the soil pH increased soil Al, so that the exchangeable Al in forest soils was 1.16 ppm, while in tea farm soils it was 1.9 ppm. Al toxicity is an important issue in this region.
    Keywords: Forest, Land use change, Soil properties, Al toxicity, organic carbon
  • O Rashidi Tazhan, H Ghazanfari, Mahtab Pir Bavahgar* Pages 83-96
    Local economy, based on animal husbandry in Northern Zagros forest leads to increase employing leaves and branches (pollarding) compared to the other parts of Zagros. Pollarding is a convenient method in forest utilization to supply fodder and it has been always trying to obtain its stable production by proper management skills. One of the most important forest management tools in a given forest is to provide up-to-date spatial maps of pollarded regions. The objective of this study was to investigate the capability of multi-temporal Landsat 8 OLI sensor for mapping pollarding areas of Northern Zagros forests. So that, we employed Landsat 8-OLI single and multi-date images acquired on 2014 and 2015. To assess the accuracy of output maps, a complete ground-truth of the study area was used to calculate the accuracy heuristics for the output maps. Different classification approaches were applied including minimum distance and maximum likelihood classifiers, artificial neural networks and fuzzy method. The classification accuracy was calculated on the basis of overall accuracy and kappa coefficient. The results indicated that artificial neural network and fuzzy classifier present the highest accuracy than the other classifiers. It was also found that utilizing the multi-temporal OLI imageries improves the accuracy over employing a single date. The results indicate that the multi-temporal imagery is moderately capable of mapping pollarded stands and classifying pollarding types, using ANN and Fuzzy classifiers.
    Keywords: OLI, Pollarding, Zagros forests, ANN