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71.
Levels of Mo, As, Se, Fe, Cu, Zn, Ni, and Pb were determined in a vegetable commonly consumed in Pakistan. Samples were collected from three different sites (Ratokala, Phularwan, and Mailowal) supplied with three different water sources. Mo and Pb in water and Mo and As in C. sativum were higher than the suggested standards at the international level. Lower bioconcentration factor and pollution load index were seen at Site-I than at other sites. A positive association was found between the rhizosphere metals and those of the vegetable at all three sites. Enrichment factor at three sites ranged from 0.28 to 10.39. The highest value of daily intake of metals was found for Fe (0.245 mg/kg/day) and of the health risk index for As (70.41) at the wastewater inundated site. It is inferred that uptake of Mo, As, Cu, Ni, and Pb through C. sativum represents a high health danger to the individuals using this vegetable.  相似文献   
72.
Accumulation of different metals and metalloids was assessed in two vegetables radish (Raphanus sativus L.) and spinach (Spinacea oleracea L.) irrigated with domestic wastewater in the peri-urban areas of Khushab City, Pakistan. In general, the metal and metalloid concentrations in radish and spinach were higher at site-II treated with sewage water than those found at site-I treated with canal water. In case of radish at both sites the levels of metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, and Pb) were below the permissible level except those of Mn, Ni, Mo, Cd, and Pb. At both sites, the transfer factor ranged from 0.047–228.3 mg kg?1 with Cr having the highest transfer factor. The metal pollution index in soil was in the following order: As > Fe > Ni > Zn > Cd > Mo > Se > Co > Pb > Mn > Cr > Cu, respectively. While in case of spinach at both sites, the concentrations of metals and metalloids in vegetable samples irrigated with canal and sewage water were observed below the permissible level except Mn, Ni, Zn, Mo, and Pb. At both sites, the transfer factor ranged from 0.038–245.4 mg kg?1 with Cr having the highest transfer factor. The metal pollution index in soil was in the following order: Cd > Ni > Co > Se > Mn > Zn > Mo > Pb > Fe > Cr > As > Cu, respectively.  相似文献   
73.
The present study was designed to assess the possible protective effects of Quercetin (QUER), a flavonoid with well-known pharmacological effects, against Dichlorvos (DDVP)-induced toxicity in vitro using HCT116 cells. The cytotoxicity was monitored by cell viability, reactive oxygen species (ROS) generation, anti-oxidant enzyme activities, malondialdehyde (MDA) production, and DNA fragmentation. The apoptosis was assessed through the measurement of the mitochondrial transmembrane potential (ΔΨm) and caspase activation. The results indicated that pretreatment of HCT116 cells with QUER, 2 h prior to DDVP exposure, significantly decreased the DDVP-induced cell death, inhibited the ROS generation, modulated the activities of catalase (CAT) and superoxide dismutase (SOD), and reduced the MDA level. The reductions in mitochondrial membrane potential, DNA fragmentation, and caspase activation were also attenuated by QUER. These findings suggest that dietary QUER can protect HCT116 cells against DDVP-induced oxidative stress and apoptosis.  相似文献   
74.
Identification of bacteria that produce carbohydrolytic enzymes is extremely important given the increased demand for these enzymes in many industries. Twenty lignocellulose-degrading bacterial isolates from Algerian compost and different soils were screened for their potential to produce different enzymes involved in biomass deconstruction. Based on 16S rRNA gene sequencing, the isolates belonged to Proteobacteria and Actinobacteria. Differences among species were reflected both as the presence/absence of enzymes or at the level of enzyme activity. Among the most active species, Bosea sp. FBZP-16 demonstrated cellulolytic activity on both amorphous cellulose (CMC) and complex lignocellulose (wheat straw) and was selected for whole-genomic sequencing. The genome sequencing revealed the presence of a complex enzymatic machinery required for organic matter decomposition. Analysis of the enzyme-encoding genes indicated that multiple genes for endoglucanase, xylanase, β-glucosidase and β-mannosidase are present in the genome with enzyme activities displayed by the bacterium, while other enzymes, such as certain cellobiohydrolases, were not detected at the genomic level. This indicates that a combination of functional screening of bacterial cultures with the use of genome-derived information is important for the prediction of potential enzyme production. These results provide insight into their possible exploitation for the production of fuels and chemicals derived from plant biomass.  相似文献   
75.
The Alitropus typus infestation has a serious influence on fish farming in Pakistan. The present study focuses on the external morphology and control of highly infested ectoparasitic isopod Alitropus typus. Sixteen morphological parameters of the whole body were measured and statistically analyzed for mean, standard error and coefficient of variation by using the student t test. Non‐significant variations were observed in the size of pereopods which depict the significance of swimming and attached to its host. For biological control, different concentrations (1000, 5000 and 10 000 ppm) of a leaf extract of four plants (i.e. Euphorbia helioscopia, Ajuga bracteosa, Cannabis sativa and Callistemon citrinus) were tested against A. typus, and the mortality rates were recorded after 12, 24 and 36 h. One way Anova and Tukey tests were used to analyze the results. The recorded percentage mortality was in the order of E. helioscopia > A. bracteosa > C. sativa, whereas C. citrinus did not showed any toxicity. Concentrations of biochemical components like carbohydrates (mg/g), proteins (mg/g), and lipids (mg/dL) of treated isopods were estimated by the phenol‐sulfuric acid process, Lowry's method and biochemistry analyzer, respectively. The protein contents of the insects tested had decreased markedly as compared to control rates, and this might be due to insecticidal stress caused by the extracts. In another biocontrol experiment, crabs were introduced along with isopods into an aquarium. It was then noted that one crab consumes an average of seven isopods/week and can act as a scavenger for dead organisms.  相似文献   
76.
Citharexylum spinosum L. (Verbenaceae) also known as Citharexylum quadrangulare Jacq . or Citharexylum fruticosum L. is an exotic tree introduced many years ago in Tunisia, specially used as a street and park ornamental tree. Essential oils (EOs) were obtained by hydrodistillation of the different parts (roots, stems, leaves, flowers and fruits; drupes) collected from trees grown in the area of Monastir (Tunisia). In total, 84 compounds, representing 90.1 – 98.4% of the whole oil composition, were identified by GC‐FID and GC/MS analyses. The root EO was distinguished by its high content in monoterpene hydrocarbons (α‐phellandrene; 30.8%) whereas that obtained from stems was dominated by sesquiterpene hydrocarbons (cuparene; 16.4%). The leaf oil was rich in an apocarotenoid derivative (hexahydrofarnesylacetone; 26%) and an aliphatic hydrocarbon (nonadecane; 14.5%). Flowers oil was rich in esters (2‐phenylethyl benzoate; 33.5%). Finally, drupes oil was rich in oxygenated sesquiterpenes (β‐eudesmol; 33.1%). Flowers oil showed a significant phytotoxic effect against lettuce seeds germination, it induces a total inhibition when tested at 1 mg/ml. Root and shoot elongation seemed to be more affected than germination. The inhibition of the shoot length varied from 3.6% to 100% and that of the root from 16.1% to 100%. The highest inhibition of 100% was detected for flower oil tested at 1 mg/ml. Our in vitro studies suggest a possible and new alternative use of Cspinosum EOs in herbicidal formulations, further experiments involving field conditions are necessary to confirm its herbicidal potential.  相似文献   
77.
Laboratory-scale experiments were conducted to examine the N2O emission during the denitrification process. For each of the 6 runs carried out, synthetic effluent was fed in a 10 l batch mixed liquor to investigate the effect of nitrite on N2O emission and Helium was continuously bubbled through the reactor at constant rate (0.12 l/min) to favour N2O transfer and detection. An increasing COD/NO3-N influent ratio from 3 to 7 was firstly applied (runs 1–3). Secondly, NO2 pulse additions were performed during run 4 and 5 (10 and 20 mg N/l, respectively). Finally, the reactor was fed with influent containing both NO2 and NO3. We showed that N2O emission was detected shortly after NO2 accumulation, few minutes after the substrate feeding. The highest emission occurred at the lower COD/NO3-N ratio (=3) and at the higher NO2 addition (20 mg N/l). In addition, the higher nitrogen conversion to N2O gas (14.4%) was obtained with an influent containing initially both NO2 and NO3. Our results suggest a direct effect of the NO2 concentration on the N2O emission. We have also confirmed the inhibitory effect of NO2 concentration on N2O reduction.  相似文献   
78.
The potential use of the immobilized Mentha arvensis distillation waste (IMADW) biomass for removal and recovery of Cu(II) and Zn(II) from aqueous was evaluated in the present study. Biosorption capacity of Cu(II) and Zn(II) on IMADW increased with increase in pH reaching a maximum at 5 for Cu(II) and 6 for Zn(II). The equilibrium sorption data agreed well with Langmuir isotherm model and pseudo-second-order kinetic model in batch mode. Cu(II) and Zn(II) uptake by IMADW was best described by pseudo-first-order kinetic model in continuous mode. Maximum Cu(II) and Zn(II) uptake by IMADW was 104.48 and 107.75 mg/g, respectively. Fourier Transform Infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were also carried out to investigate functional groups and surface changes of biomass. The results showed that IMADW biomass is a potential biomaterial to remove Cu(II) and Zn(II) ions with a high biosorption capacity from aqueous solutions.  相似文献   
79.
A significant portion of organic phosphorus comprises of phytates which are not available to wheat for uptake. Hence for enabling wheat to utilize organic phosphorus in form of phytate, transgenic wheat expressing phytase from Aspergillus japonicus under barley root-specific promoter was developed. Transgenic events were initially screened via selection media containing BASTA, followed by PCR and BASTA leaf paint assay after hardening. Out of 138 successfully regenerated To events, only 12 had complete constructs and thus further analyzed. Positive T1 transgenic plants, grown in sand, exhibited 0.08–1.77, 0.02–0.67 and 0.44–2.14 fold increase in phytase activity in root extracts, intact roots and external root solution, respectively, after 4 weeks of phosphorus stress. Based on these results, T2 generation of four best transgenic events was further analyzed which showed up to 1.32, 56.89, and 15.40 fold increase in phytase activity in root extracts, intact roots and external root solution, respectively, while in case of real-time PCR, maximum fold increase of 19.8 in gene expression was observed. Transgenic lines showed 0.01–1.18 fold increase in phosphorus efficiency along with higher phosphorus content when supplied phytate or inorganic phosphorus than control plants. Thus, this transgenic wheat may aid in reducing fertilizer utilization and enhancing wheat yield.  相似文献   
80.
Adams-Oliver syndrome (AOS) is defined by the combination of aplasia cutis congenita (ACC) and terminal transverse limb defects (TTLD). It is usually inherited as an autosomal-dominant trait, but autosomal-recessive inheritance has also been documented. In an individual with autosomal-recessive AOS, we combined autozygome analysis with exome sequencing to identify a homozygous truncating mutation in dedicator of cytokinesis 6 gene (DOCK6) which encodes an atypical guanidine exchange factor (GEF) known to activate two members of the Rho GTPase family: Cdc42 and Rac1. Another homozygous truncating mutation was identified upon targeted sequencing of DOCK6 in an unrelated individual with AOS. Consistent with the established role of Cdc42 and Rac1 in the organization of the actin cytoskeleton, we demonstrate a cellular phenotype typical of a defective actin cytoskeleton in patient cells. These findings, combined with a Dock6 expression profile that is consistent with an AOS phenotype as well as the very recent demonstration of dominant mutations of ARHGAP31 in AOS, establish Cdc42 and Rac1 as key molecules in the pathogenesis of AOS and suggest that other regulators of these Rho GTPase proteins might be good candidates in the quest to define the genetic spectrum of this genetically heterogeneous condition.  相似文献   
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