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11.
ESR increased at all concentrations and exposures to LAS. However, increases were more pronounced at LC50 for 24 h and minimum at the end of 96 h.  相似文献   
12.
This study reports the effects of low level developmental Pb exposure on specific brain regions like hippocampus, cerebellum and cerebral hemispheres of antioxidant enzyme activities. Wistar dams were exposed to 50 ppm, 100 ppm and 500 ppm of Pb acetate in drinking water during pregnancy and lactation (gestation day 6 through PND 21 (post natal day) and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione reductase (GR) were determined in the hippocampus, cerebellum and cerebral hemispheres of pups during treatment period (PND 7, 14, and 21 days) and also during withdrawl period (PND 35, 45, 60 and 90 days). During treatment period, SOD activity significantly (p < 0.05) decreased in all regions of all the treated groups with maximum decrease in 500 ppm treated group of 21 days, while GSH-Px and GR activities increased with maximum increase in 21 days aged 500 ppm group. During withdrawl period, the activities of all enzymes were significantly (p < 0.05) reversed. Thus the perinatal exposure of dams to variable dosages of low level lead results in characteristic neurochemical alterations in rat brain regions due to impaired antioxidants function.  相似文献   
13.
The catfish, H. fossilis were exposed to endosulfan for 30 days at sub-lethal concentration (0.002 ppm) during different phases of its annual reproductive cycle. Its impact on total (TP) and different phospholipids- phosphatidylcholine (PC), phosphatidylserine (PS), phosphatdylinositol (Pl) and phosphatidylethanolamine (PE) were measured in liver plasma and ovary. On pesticide exposure, during preparatory phase, the hepatic TP PC and PE were declined. The plasma levels of TP, PC and PS were declined with the elevation of PE whereas in ovary only PC was lowered after endosulfan exposure. During pre-spawning phase, the hepatic TP, PC and PE declined in liver plasma and ovary after endosulfan exposure. During spawning phase, only plasma and ovarian phospholipids showed decrease in their levels following endosulfan exposure. In the post-spawning phase, endosulfan elevated the levels of TP, PC and PS in ovary but had no effect on their levels in liver and plasma. During resting phase, the TP, PC and Pl were found to be decreasing its levels. Thus it appears that this pesticide interfere with phospholipids metabolism during annual reproductive cycle of this species.  相似文献   
14.
Environmental Science and Pollution Research - The total number of inhabitants on the Earth is estimated to cross a record number of 9 × 103 million by 2050 that present a unique challenge to...  相似文献   
15.
The current research study focuses to formulate the biosynthesized silver nanoparticles for the first time from silver acetate using methanolic root extracts of Diospyros sylvatica, a member of family Ebenaceae. TEM analysis revealed the average diameter of Ag NPs around 8 nm which is in good agreement with the average crystallite size (10 nm) calculated from X-ray Diffraction (XRD) analysis. Further the study has been extended to the antimicrobial activity against test pathogenic Gram (+) ve, Gram (−) ve bacterial and fungal strains. The bioinspired Ag-NP showed promising activity against all the tested bacterial strains and the activity was enhanced with increased dosage levels.  相似文献   
16.
Oil palm industries produce an enormous quantity of lignocellulosic biomass; in the form of large leaves of palm tree, pruned fronds (OPF) and oil palm trunks (OPT) at the plantations site. Besides this, the processing of fresh fruit bunches in the oil mills generates empty fruit bunches (EFB), shells, kernel cake and mesocarp fibers. The proper management of this burgeoning waste and its disposal is an ardent task and creates environmental hazards. In order to deal with the biomass residues, the urgent need is that it should be transformed into resources with industrial utility. As the economic development has resulted in the significant increased demand for paper, the industry is looking for eccentric sources to fulfill the requirement. The pulp and paper industry preferred use of coniferous and deciduous trees for papermaking because their cellulose fibers in the pulp make durable paper. With improvements in pulp processing technology, fibers of almost any non-wood of plants species like bamboo, cereal straw, sugarcane, flax, hemp and jute can be used for paper pulp. Substituting this lignocellulosic material can reduce the burden on forest while supporting the natural biodiversity. The present review deals with the possibilities of using oil palm biomass as a raw material for pulp and papermaking, as this would ameliorate its waste management problem. The potential of oil palm biomass and the challenges regarding its use in papermaking are discussed. The use of oil palm biomass will apparently prove that the oil palm industry is ecofriendly in every aspect of its activities and aid in sustainability of forest ecosystem.  相似文献   
17.
In this study, the effect of silicon (Si) addition on cadmium (Cd) toxicity in rice seedlings was investigated. After a series of screening experiments, 50 μmol·L?1 of Cd and 10 μ mol·L?1 of Si were selected. Treatment of rice seedlings with Cd (50 μ mol·L?1) resulted in significant accumulation of this metal in roots and shoots. The data revealed that accumulation of Cd resulted in oxidative stress in rice seedlings as evidenced by increased accumulation of hydrogen peroxide (H2O2) and malondialdehyde (MDA; a peroxidation product of lipids). However, addition of Si (10 μ mol·L?1) together with Cd prevented accumulation of Cd, H2O2 and MDA. Antioxidant capacity was decreased by Cd but enhanced by Si addition. Cd decreased the length and frequency of root hairs, stomatal frequency, and distorted leaf mesophyll cells and vascular bundles. However, addition of Si together with Cd reduced these abnormalities. The results showed that addition of exogenous Si protected rice seedlings against Cd toxicity by preventing Cd accumulation and oxidative stress (H2O2 and MDA accumulation) by increasing Si accumulation and antioxidant capacity, which maintained the structure and integrity of leaf and root.  相似文献   
18.
This work was undertaken to ascertain the impact of different fluence rates of ultraviolet-B (UV-B) radiation on two cyanobacterial biofertilizers, Phormidium foveolarum and Nostoc muscorum, growing under copper toxicity. Copper (2 and 5?µmol?L?1) and high UV-B fluence rate (UV-BH; 1.0?µmol?m?2?s?1) decreased the growth, pigment content, photosynthetic oxygen yield, phosphate uptake, and acid phosphatase activity in both the strains analyzed after 24 and 72?h of experiments, and combined exposure further enhanced the toxic effects. Respiration and alkaline phosphatase activities were stimulated appreciably. The damaging effect was shown on the order on pigments: phycocyanin?>?chlorophyll a?>?carotenoids, and on photosystems: whole chain photosynthetic reaction?>?photosystem II?>?photosystem I. Partial recovery in the photosystem II activity in the presence of artificial electron donors; diphenyl carbazide (DPC), hydroxylamine (NH2OH), and manganese chloride (MnCl2) pointed out the interruption of electron flow on the oxidation side of photosystem II. Unlike UV-BH, low UV-B fluence rate (UV-BL; 0.1?µmol?m?2?s?1), rather than causing damaging effect partially, alleviated the toxic effects of Cu. This study suggests that the cyanobacterium P. foveolarum is less sensitive against UV-BH and excess Cu (2 and 5?µmol?L?1), thus P. foveolarum may be used as a biofertilizer for sustainable agriculture.  相似文献   
19.
Environmental Science and Pollution Research - At present, food security is a matter of debate of global magnitude and fulfilling the feeding requirement of?&gt;?8 billion human...  相似文献   
20.
The present work investigated the levels of total volatile organic compounds (TVOC) and benzene, toluene, ethylbenzene, m/p-xylene, and o-xylene (BTEX) in different microenvironments in the library of Jawaharlal Nehru University in summer and winter during 2011–2012. Carcinogenic and non-carcinogenic health risks due to organic compounds were also evaluated using US Environmental Protection Agency (USEPA) conventional approaches. Real-time monitoring was done for TVOC using a data-logging photo-ionization detector. For BTEX measurements, the National Institute for Occupational Safety and Health (NIOSH) standard method which consists of active sampling of air through activated charcoal, followed by analysis with gas chromatography, was performed. Simultaneously, outdoor measurements for TVOC and BTEX were carried out. Indoor concentrations of TVOC and BTEX (except benzene) were higher as compared to the outdoor for both seasons. Toluene and m/p-xylene were the most abundant organic contaminant observed in this study. Indoor to outdoor (I/O) ratios of BTEX compounds were generally greater than unity and ranged from 0.2 to 8.7 and 0.2 to 4.3 in winter and summer, respectively. Statistical analysis and I/O ratios showed that the dominant pollution sources mainly came from indoors. The observed mean concentrations of TVOC lie within the second group of the Molhave criteria of indoor air quality, indicating a multifactorial exposure range. The estimated lifetime cancer risk (LCR) due to benzene in this study exceeded the value of 1?×?10?6 recommended by USEPA, and the hazard quotient (HQ) of non-cancer risk came under an acceptable range.  相似文献   
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