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Macro- and microelement content and health risk assessment of heavy metals in various herbs of Iran Full text
2020
Moghaddam, Mohammad | Mehdizadeh, Leila | Sharifi, Zahra
In this study, element content and health risk of the most popular herbs from Iran were evaluated. The samples of raw materials from 30 different herbs were purchased from the local markets of Iran. The concentration levels of some elements including macroelements (N, P, K, Ca, and Mg), micronutrients (Fe, Zn, Cu, Mn, and Na), and heavy metals (Cd, Ni, and Pb) of studied herbs were evaluated. The potential of health risks was calculated by Estimated Daily Intake (EDI), Target Hazard Quotient (THQ), and Hazard Index (HI). The analysis of variance (ANOVA) is used to test a hypothesis about differences between the mean values. The highest levels of Ca (20,000 ± 26.3 mg/kg), Mg (9600 ± 45.4 mg/kg), N (59,955 ± 11.55 mg/kg), P (6544 ± 20 mg/kg), and K (56,563.2 ± 18 mg/kg) were found in Zataria multiflora, Malva sylvestris, Acasia arbus, Cannabis sativa, and Amomum subulatum, respectively. In addition, the highest concentration levels of Fe (987 ± 75.27 mg/kg), Zn (1187.5 ± 10 mg/kg), Cu (64.2 ± 2 mg/kg), Mn (272.3 ± 66.62 mg/kg), and Na (2658.8 ± 20.3 mg/kg) were recorded in Bunium persicum, Peganum harmala, Papaver somniferum, Alpinia officinalis, and Cuminum cyminum, respectively. Acasia arbus, Anethum graveolens, and Malva sylvestris showed the highest concentration of Ni (6.07 ± 0.04 mg/kg), Cd (1.64 ± 0.16 mg/kg), and Pb (9.27 ± 0.25 mg/kg). Based on performed health risk assessment on the studied plants, EDI, THQ, and HI values of all of them were less than 1. This study indicated that there were several harmful elements in the herbs. The healthier plant species are those with the least concentration of Pb, Ni, and Cd, which include Vitex agnus-custus and Teucrium polium. On the other hand, the toxic plants with a higher concentration of Pb, Ni, and Cd included Malva sylvestris, Acasia arbus, and Anethum graveolens. In addition, evaluation of human risk assessment is an important factor for investigating the concentration of heavy metals harmful for human beings.
Show more [+] Less [-]Evaluation of the complex dynamic modulus of asphaltic concretes manufactured with construction and demolition waste (CDW) aggregates Full text
2020
Esparza, Luis-Antonio | Ossa, Alexandra | Botero Toro, Eduardo
Currently, there is an overexploitation of natural resources worldwide due to the need to build various types of civil engineering infrastructure, such as buildings, bridges, housing and, in particular, roads. A large number of countries, including Mexico, additionally do not apply adequate treatment to the material resulting from the demolition of this type of work. Both situations generate significant environmental damage and contribute to the non-sustainability of the road construction sector. This research assesses the linear viscoelastic (LVE²) behavior of asphalt concrete specimens made with different combinations of mineral aggregate and construction and demolition waste (CDW). Complex dynamic modulus tests were performed in compression on cylindrical samples at different temperatures and frequency loading. The ANOVA analysis of test results indicate that the stiffness of the different asphalt concretes evaluated, represented by the complex dynamic modulus, tends to decrease with the temperature and increase with load frequency, which are typical of materials with viscous characteristics. The stiffness of the asphalt concrete evaluated does not show significant changes as the CDW aggregate content varies.
Show more [+] Less [-]The extract of aquatic macrophyte Carex cinerascens induced colony formation in bloom-forming cyanobacterium Microcystis aeruginosa Full text
2020
Li, Lin | Jing, Xiao-ling | Wang, Ling | Zeng, Zhi-gao | Chen, Wen-hong | Zhai, Jia-hao | Qi, Si-qin
Colony formation in Microcystis aeruginosa played important roles in blooms formation. To study the effects of plant allelopathy on colony formation in M. aruginosa, unicellular M. aeruginosa was cultivated under laboratory conditions treated with various extract concentration of Carex cinerascens. The growth of M. aeruginosa in the treatments with 0.05 and 0.1 mg L⁻¹ extract of C. cinerascens was promoted but the growth in the treatments with 1.5, 3.0, and 6.0 mg L⁻¹ C. cinerascens extract was inhibited. Obvious colony formation in M. aeruginosa was observed in all treatments while no colony formation was detected in the control. The cell number per colony at the first day was the largest and decreased along with culture time. The cell number per colony in the control ranged from 3.0 to 4.0 during the experiment. However, the values in the five treatments at the first day were 33, 80, 58, 41, and 30, respectively. A positive exponential relationship between cell number per colony of M. aeruginosa and extracellular polysaccharides (EPS) content was found as well. Compared the fold-increase in cell number per colony and the fold-increase in total biomass of M. aeruginosa at various day, it was found that colony formation induced by extract of C. cinerascens was primarily dependent on promotion of cell adhesion during the first 2 days. The cell number per colony decreased afterward was due to the increasing proportion of single cells in the culture because single cells had a great higher growth rate than M. aeruginosa colonies under culture condition. Our results suggested that plant allelopathy be one of the major factor contributing to colony formation in M. aeruginosa.
Show more [+] Less [-]The potential applications of picotechnology in biomedical and environmental sciences Full text
2020
Qasim, Muhammad Zeeshan | Hammad, Hafiz Mohkum | Abbas, Farhat | Shafqat, Saeed | Bakhat, Hafiz Faiq | Nasim, Wajid | Farhad, Wajid | Rabbani, Faiz | Shah, Fahad
Picotechnology development in vast disciplines is mainly attributed to the research and development (R and D) on nanotechnology. Being a parent technology, nanotechnology is the cornerstone of picotechnology. Like nanotechnology, the reference standard for picotechnology is nature, the cellular and subcellular functioning. Some studies have highlighted that the functional margin of similar type of molecules at picoscale (10⁻¹²) goes higher than at nanoscale (10⁻⁹). In this review, the potential applications of picotechnology have been evaluated especially in the disciplines of biomedical and environmental sciences. Extended surface area and improved electrical, chemical, optical, and mechanical properties make picotechnological products even better than nanomaterials. The fundamental objective of this study is to bring the attention of the scientific world towards the picoscale interventions and to highlight the wide scope of picotechnology as a newly emerging technology with applications in numerous sectors. Picotechnology has made it possible to measure very small structure in advance biomedical and environmental sciences studies. Adequate developments in picotechnology will certainly change human lives in near future because it will make possible for the research world to dive into systems and structures on picoscale. It will render a platform through which explorers can travel into ultra-small areas, which will lead to the creation of new dimensions as well as new opportunities. Eventually, in future, the picotechnology will become smaller enough to give birth to femtotechnology (10⁻¹⁵) in real-world applications.
Show more [+] Less [-]Environmental monitoring and prediction of land use and land cover spatio-temporal changes: a case study from El-Omayed Biosphere Reserve, Egypt Full text
2020
Hashim, Ahmed M. | Elkelish, Amr | Alhaithloul, Haifa A. | El-hadidy, Shaimaa M. | Farouk, Haitham
Environmental monitoring, using the techniques of remote sensing (RS) and geographic information systems (GIS), allows the production of time efficient, cost-effective, and reliable surveillance and tracking data. Anthropogenic activities appear to be the major trigger of environmental changes, including land use and land cover (LULC) changes, while natural causes have only a minor impact in most cases. The Omayed Biosphere Reserve (OBR) stands as one of the Egyptian protected areas most highly affected by massive unplanned human activities. Thus, the main objective of this study is to determine the spatio-temporal changes in the OBR over a 35-year period using five Landsat (5 ETM images and 8 OLI-TIRS) imageries, with the specific aim of measuring change rates, trends, and magnitudes of LULC changes between 1984 and 2019 with the topography for planning and selection of developmental strategies. The Normalised Difference Vegetation Index is used to identify the vegetation characteristics of different eco-regions and delivers useful information for the study of vegetation health and density. Normalised Difference Built-up Index can likewise be used to quote built-up areas. Unsupervised classification was used to classify LULC patterns. Six classes were recognised: water bodies, coastal sand, urban areas, cultivated land, newly reclaimed areas, and bare soil. Our results reveal that about 33.55% of OBR land cover has transformed into other forms. Cultivated land and urban regions increased by about 143.5 km² and 56.17 km² from 1984 to 2019, respectively. Meanwhile, bare soil decreased to around 209.5 km² in 2019. In conclusion, the conversion of bare soil into urban land and cultivated areas is the major change in the last 35 years in the OBR. Over the past three decades, the OBR has faced radical and imbalanced changes in its natural habitats. Therefore, monitoring and management of LULC changes are crucial for creating links between policy decisions, regulatory actions, and following LULC activities in the future, especially as many potential risks still exist in the remaining regions of the OBR.
Show more [+] Less [-]Surface water quality assessment in a semiarid Mediterranean region (Medjerda, Northern Tunisia) using partial triadic analysis Full text
2020
Slimani, Noura | Jiménez, Juan José | Guilbert, Éric | Boumaïza, Moncef | Thioulouse, Jean
A range of methods have been developed specifically to analyze several tables of data simultaneously (variable × space × time) in the field of ecological research, although they have been less widely used to examine water quality. In this study, we assessed the spatiotemporal variability of water quality in the Medjerda River basin (Northern Tunisia). Partial triadic analysis (PTA) provides an effective framework for the assessment of spatiotemporal variability of water quality in the Medjerda River basin (Northern Tunisia). Fourteen physicochemical variables were monitored from 12 sampling sites monthly during 2013. PTA allowed correlations among different physicochemical parameters to be identified and to assess overall water quality in the Medjerda River. Salinity (S), Cl⁻, SO₄²⁻, Ca²⁺, and Mg²⁺ ions were associated with intensive agricultural activities (agricultural pollution sources) leading to salinization. However, NH₄⁺, PO₄³⁻, chemical oxygen demand (COD), and biochemical oxygen demand (BOD₅) we more strongly associated with polluted urban sites. PTA helped illustrate that strong links exist between land uses and adjacent water quality. The advantages of this multi-table method approach for water quality monitoring include as follows: (1) identifying common multivariate spatial structures and problems associated with maintaining water quality, (2) allowing identification of consistent patterns in water chemistry, and (3) allowing analysis on the temporal variability of water chemistry.
Show more [+] Less [-]Characteristics of water-soluble organic acids in PM2.5 during haze and Chinese Spring Festival in winter of Jinan, China: concentrations, formations, and source apportionments Full text
2020
Tang, Shuting | Zhou, Xuehua | Zhang, Jingzhu | Xue, Likun | Luo, Yuanyuan | Song, Jie | Wang, Wenxing
PM₂.₅ aerosols from Jinan (36°256′N, 117°106′E) in the North China Plain region were investigated for water-soluble organic acids (WSOAs, i.e., oxalic acid, formic acid, acetic acid, methanesulfonic acid (MSA), and lactic acid) during 30 December 2016 to 21 February 2017. The average PM₂.₅ concentration was 168.77 μg/m³ with about 90.74% samples beyond the National Ambient Air Quality (NAAQ) standards (Grade II). The total concentration of the measured WSOAs averaged at 1.34 μg/m³, contributing to 0.80% of PM₂.₅ mass. In the observation, acetic acid was the most abundant WSOA, followed by oxalic acid, lactic acid, formic acid, and MSA. During the period, serious haze events frequently happened. The average concentrations of PM₂.₅ and every WSOA species were higher in haze than those in non-haze. The correlations among species suggested that WSOAs in haze had complicated sources and secondary pathways, especially aqueous-phase reactions which played an important role on WSOAs. The concentrations of WSOAs declined in the Spring Festival compared with those in the non-Spring Festival due to holiday effect. Fireworks burning during the Spring Festival had different influences on WSOAs with slight increases for acetic acid and lactic acid. Five source factors were identified by positive matrix factorization (PMF) model for five WSOAs, respectively, and the results revealed that secondary reactions were the main sources of WSOAs in haze.
Show more [+] Less [-]Chitosan nanoparticles from Artemia salina inhibit progression of hepatocellular carcinoma in vitro and in vivo Full text
2020
Elkeiy, Mai M. | Khamis, Abeer A. | El-Gamal, Mona M. | Abo Gazia, Maha M. | Zalat, Zeinb A. | El-Magd, Mohammed A.
This study was conducted to evaluate the effect of chitosan nanoparticles (CNPs) isolated from Artemia salina against hepatocellular carcinoma (HCC) both in vitro (HepG2) and in vivo (diethylnitrosamine-induced HCC in rats) and to investigate the involved underlying mechanisms. Administration of CNPs decreased HCC progression as evidenced by (1) induced HepG2 cell death as detected by MTT assay; (2) induced necrosis as indicated by acridine orange/propidium iodide (AO/PI) red staining, annexin V/7-AAD positive staining (detected by flow cytometry), and upregulated expression of necrosis markers (PARP1 and its downstream target, RIP1 genes), but no effect on apoptosis as revealed by insignificant changes in caspase 3 activity and mRNA levels of Bax and AIF; (3) increased intracellular ROS and decreased mitochondrial membrane potential in HepG2; (4) decreased liver relative weight, serum levels of liver enzymes (ALT, AST, and ALP), total bilirubin, and cancer markers (AFP and GGT), number and area of GST-P positive tumor nodules; and (5) reduced oxidative stress (decrease in MDA levels) and increased activities of SOD, CAT, and GPx enzymes in rat liver. The preventive (pre-treatment) effect of CNPs was better than the therapeutic (post-treatment) effect. Collectively, administration of CNPs inhibited HCC progression in vitro and in vivo, possibly through induction of necrosis, rather than apoptosis, and induction of antioxidant enzyme activities in vivo, but with stimulation of ROS production in vitro. Thus, CNPs could be used as a promise agent for treating HCC after application of further confirmatory clinical trials.
Show more [+] Less [-]The role of shadow economies in ecological footprint quality: empirical evidence from Turkey Full text
2020
Köksal, Cihat | Işik, Mehtap | Katircioğlu, Salih
The purpose of this research study is to investigate the role of shadow economies in the levels of ecological footprint for the case of Turkey. Annual data set ranging from 1961 to 2014 was used with this respect. The results of this study verify the long-term and positively elastic impact of shadow economic activities on the level of ecological footprint in Turkey; that is, 1 % change in shadow economic activities results in a 1.008% change in ecological footprint in the same direction. This study, therefore, reaches a significant conclusion that in Turkey, shadow economies are long-term and essential drivers of environmental pollution.
Show more [+] Less [-]Heat treatment and protective potentials of luteolin-7-O-glucoside against cisplatin genotoxic and cytotoxic effects Full text
2020
Maatouk, Mouna | Abed, Besma | Bouhlel, Ines | Krifa, Mounira | Khlifi, Rihab | Ioannou, Irina | Ghedira, Kamel | Ghedira, Leila Chekir
Cisplatin is an effective chemotherapeutic agent that has pronounced adverse effects. Using flavonoids is currently eliciting considerable interest. During extraction and conditioning, they usually undergo several physical treatments such as heat treatment, although it is not known whether thermal treatment might influence the pharmacological effects of flavonoids such as luteolin-7-O-glucoside (L7G). This study was undertaken to explore the protective role of native and heated L7G against DNA damage and oxidative stress induced by cisplatin. Balb/c mice were administered L7G before a single intraperitoneal injection of cisplatin (10 mg/kg). Animals were sacrificed 24 h after treatment with drugs. The geno-protective role of native and heated L7G was evaluated by comet assay. In addition to monitoring the activities of antioxidant enzymes, levels of malondialdehyde and reduced glutathione were assessed in the liver, kidney, brain, and spleen tissues. The results of the present study demonstrate that both heated and native L7G, at a dose of 40 mg/kg b.w, were able to reduce the genotoxicity of cisplatin. They attenuate the oxidative stress (malondialdehyde, catalase, GPx, SOD, and GSH) and tissue damage (creatinine, IFNγ). Heat treatment did not alter the antigenotoxic effect observed for native L7G and showed similar effects to those of native L7G for all of the evaluated parameters. Our study reveals that L7G attenuates the side effects of anticancer drug and heat treatment did not alter his antigenotoxic and antioxidant the potential.
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