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Mutagenicity assessment of aerosols in emissions from wood combustion in Portugal
2012
Vu, B. | Alves, C.A. | Gonçalves, C. | Pio, C. | Gonçalves, F. | Pereira, R.
Polycyclic aromatic hydrocarbon (PAH) extracts of fine particles (PM₂.₅) collected from combustion of seven wood species and briquettes were tested for mutagenic activities using Ames test with Salmonella typhimurium TA98 and TA100. The woods were Pinus pinaster (maritime pine), Eucalyptus globulus (eucalypt), Quercus suber (cork oak), Acacia longifolia (golden wattle), Quercus faginea (Portuguese oak), Olea europea (olive), and Quercus ilex rotundifolia (Holm oak). Burning experiments were done using woodstove and fireplace, hot start and cold start conditions. A mutagenic response was recorded for all species except golden wattle, maritime pine, and briquettes. The mutagenic extracts were not correlated with high emission factors of carcinogenic PAHs. These extracts were obtained both from two burning appliances and start-up conditions. However, fireplace seemed to favour the occurrence of mutagenic emissions. The negative result recorded for golden wattle was interesting, in an ecological point of view, since after confirmation, this invasive species, can be recommended for domestic use.
Afficher plus [+] Moins [-]Accumulation of cadmium by some crops around a factory producing phosphate fertilizers in Sfax (Tunisia) | Accumulation du cadmium par quelques especes vegetales cultivees aux environs d'une usine d'engrais phosphates a Sfax (Tunisie)
1999
Mezghani, I. (Faculte des Sciences de Fax (Tunisie). Departement de Biologie) | Boukhris, M. | Chaieb, M.
La pollution des ecosystemes terrestres par du cadmium d'origine industrielle (usine d'engrais phosphates) se traduit par des taches necrotiques au niveau des feuilles et par une accumulation importante de cet element dans ces feuilles et dans les horizons superficiels des sols. A proximite de la source d'emission, les taux de cadmium dans le sol depassent 10 fois les valeurs normales. Au niveau des feuilles, elles sont 10 a 30 fois plus elevees que chez les temoins et dependent de la nature de l'espece, de la distance (correlation negative) et des conditions topographiques
Afficher plus [+] Moins [-]Air biomonitoring of heavy metals and polycyclic aromatic hydrocarbons near a cement plant
2014
Baldantoni, Daniela | De Nicola, Flavia | Alfani, Anna
Biomonitoring studies, based on pollutant accumulation analyses in tree leaves, allow evaluating the impact caused by air–dispersed pollutants on ecosystems, providing useful data, complementary to those obtained by instrumental monitoring. In particular, leaves of sclerophylls present morphological characteristics, such as the presence of hairs and of a tick cuticle, making them particularly useful in bioaccumulation studies. The first aim of this research was to compare heavy metal (HM) and polycyclic aromatic hydrocarbon (PAH) leaf accumulation capabilities of two Mediterranean tree species. The second aim was to evaluate the impact of a cement plant and/or of other anthropogenic activities occurring in industrial and urban areas on HM and PAH depositions. For these purposes, holm oak (Quercus ilex L.) and olive (Olea europaea L.) leaves collected along a transect industrial–urban–remote sites in southern Italy were employed. A different accumulation degree was observed for the two species. For HMs, Q. ilex leaves had the highest concentrations. The results showed that the influence of the cement plant emissions on pollutant concentrations was substantial in the area closer to clinker production and storage with the highest Pb, Ni, V, Cr, Fe, indeno(1,2,3–c,d)pyrene, benzo(g,h,i)perylene and benzo(a)anthracene leaf concentrations. However, Q. ilex leaves showed high HM and PAH concentrations also in the urban site, in relation to vehicular traffic emissions and depositions. The comparison of the results of the present study with those from the literature indicates that the overall air quality of the studied sites is not particularly compromised, also in proximity of the cement production. The use of holm oak should be preferred in biomonitoring due to its wider distribution compared to O. europaea.
Afficher plus [+] Moins [-]Production of hydroxytyrosol rich extract from Olea europaea leaf with enhanced biological activity using immobilized enzyme reactors
2022
As olive leaves constitute the main by-product of the olive oil industry with important environmental and economic impact, there is an increasing demand for its valorization. In the present work, we report the development and application of immobilized enzyme batch bioreactors for the chemo-enzymatic treatment of an aqueous Olea europaea leaf extract rich in oleuropein to produce an extract enriched in hydroxytyrosol and other oleuropein hydrolysis products. To this end, a robust biocatalyst was developed through the immobilization of β-glucosidase on chitosan-coated magnetic beads which exhibited high hydrolytic stability after 240 h of incubation at 37 °C. The biocatalyst was successfully used in both a rotating bed-reactor and a stir-tank reactor for the modification of the olive leaf extract leading to high conversion yields of oleuropein (exceeding 90%), while an up to 2.5 times enrichment in hydroxytyrosol was achieved. Over 20 phenolic compounds (from different classes of phytochemicals such as flavonoids, secoiridoids, and their derivatives) were identified, in the extract before and after its modification through various chromatographic and spectroscopic techniques. Finally, the biological activity of both extracts was evaluated. Compared to the non-modified extract, the modified one demonstrated 20% higher antioxidant activity, seven-fold higher antibacterial activity, and enhanced cytotoxicity against leiomyosarcoma cells.
Afficher plus [+] Moins [-]Assessment of heterogeneity of two cultivars of Olea europaea based on the study of their Ole e 1 protein content
2021
Olive pollen is one of the main causes of allergic disease in the Mediterranean area. Ten different proteins with allergenic activity have been described in olive pollen, with major allergen Ole e 1. Olea europaea L. may cause allergenic effects of different severity depending on the Ole e 1 content of cultivars. In this paper, we aimed to assess the heterogeneity of two olive cultivars concerning concentrations of the major allergen Ole e 1 during a period of 2 years. Pollens from two most common olive cultivars, known as “Gemlik” and “Celebi,” were analyzed on regular basis. Ole e 1 amounts were measured by double-sandwich enzyme-linked immunosorbent assay (ELISA). The results were expressed as μg of Ole e 1 per μg of total freeze-dried extract. Comparisons of Ole e 1 levels were made both between individual trees and between cultivars. It was analyzed the influence of some meteorological parameters on pollen counts/allergenic content on a local scale, for 2 years. Pollen sampling was carried out continuously for 2 years, using a Hirst-type volumetric trap. “Gemlik” had the higher value (mean ± standard deviation) of Ole e 1 content (2.44 ±0.70 and 1.87 ±1.03 μg/μg, respectively) when compared to “Celebi” (2.16 ±0.86 and 0.20 ±0.30 μg/μg, respectively) in the years 2013 and 2015. In our research, daily variations were observed in pollen samples of two olive cultivars and even different trees of the same cultivar. Furthermore, during certain sampling days, discrepancies between airborne pollen counts and Ole e 1 concentrations were detected for both cultivars. It was found that meteorological changes, especially temperature and precipitation fluctuations, could affect airborne pollen and Ole e 1 allergen levels in the atmosphere. Therefore, pollen samples of different O. europaea cultivars demonstrated great differences in Ole e 1 content. We believe that these findings were a result of alternate bearing behavior modulated by meteorological factors.
Afficher plus [+] Moins [-]Protective effects of olive leaf extract against reproductive toxicity of the lead acetate in rats
2021
Ahmed, Harith Abdulrhman | Ali, Huda Abdullah | Mutar, Thulfiqar Fawwaz
Lead acetate (PbAc) is one of the toxic metals in the environment which causes many effects on different organs of the body. And due to the importance of the olive tree, with its healthy and protective elements against many diseases, the leaf extract of this tree was chosen in our study. Therefore, the aim of this study was to investigate the role of olive leaf (Olea europea L.) extract (OLE) against PbAc-induced sperm toxicity, sex hormone changes, oxidative stress, and histopathological changes in rats. Twenty male Wistar rats were divided into four groups (group 1, as control; group 2, OLE; group 3, PbAc; group 4, PbAc+OLE). In the PbAc group, the body weight, testis and epididymis weights, sexual hormones, sperm characteristics, GR, GPx, GST, GSH, SOD, and CAT were significantly decreased, and the sperm abnormality and TBARS level were significant increase when compared with control and OLE groups. Also, numerous damages to testicular tissue were observed in the PbAc group when compared to the control group, while the treatment with OLE in the fourth group led to improvement of sex hormones, semen characteristics, oxidative stress, and testicular tissue damage caused by PbAc. It can be concluded that OLE has a protective and ameliorative effects against PbAc-induced oxidative stress, apoptosis and alterations in testicular tissue, and sperm quality in rats.
Afficher plus [+] Moins [-]Short-time irrigation on young olive tree (Olea europaea L. cv. Chemlali) with untreated industrial poultry wastewater: investigation of growth parameters and leaves chemical composition
2021
The purpose of this study was to evaluate the short-term irrigation effect with industrial poultry wastewater on young olive trees (Olea europaea L. cv. Chemlali). Industrial poultry wastewater can be considered as a bio-fertilizer due to its richness in nutritive elements (SO₄²⁻, HCO₃⁻, total nitrogen, and K⁺). The physicochemical analysis of wastewater showed a high concentration of TSS, COD, BOD, COT, NO₃⁻, and conductivity. Measurements indicated that poultry wastewater enhanced plant growth, leaves dry matter, and ashes in comparison with tap water, as well as poultry wastewater diluted with tap water; however, a decrease in total soluble sugars (glucose and fructose) was detected in leaves. The determination of fatty acid profile of young olive trees leaves irrigated with poultry wastewater showed richness on saturated fatty acids in comparison with mono- and poly-unsaturated ones. In addition, oleic acid (C₁₈:₁) presented the lowest content in leaves of trees irrigated with poultry wastewater irrigation. According to those results, poultry wastewater lends itself to being a hydric alternative and at the same time a source of nutrients that can help fill the water deficit in semi-arid countries and avoid costly waste disposal for slaughterhouses.
Afficher plus [+] Moins [-]Rhodamine B Dye Adsorption onto Biochar from Olive Biomass Waste
2021
Albanio, Isadora Iensen | Muraro, Pâmela Cristine Ladwig | da Silva, William Leonardo
Olive biomass waste (Olea europaea L.) is a by-product of vegetable oil extraction processing produced in ever-increasing quantities, becoming an environmental liability when not destination or treated correctly. Thus, the work aimed to study the application of olive biomass waste to preparation of adsorbent material (biochar) to rhodamine B (RhB) dye removal. For the preparation of the biochar, activation/carbonization process was used, where for chemical activation, the ZnCl₂ was used as activating reagent, in the proportion of 1:2 w/w, and for the carbonization, used a heating rate of 10 °C min⁻¹ to 600 °C for 240 min. Materials were characterized by X-ray diffraction (XRD), zeta potential (ZP), and Fourier transform infrared spectroscopy (FTIR), and its adsorption potential to remove RhB dye from aqueous media was verified, through kinetic, equilibrium, and thermodynamic study. About kinetic adsorption, the pseudo-first-order model showed satisfactorily represented. Moreover, Freundlich model was suitable to represent the adsorption equilibrium of the RhB dye. The maximum value for adsorption capacity was 263.71 mg g–¹, and the adsorption process was thermodynamically spontaneous, favorable, and endothermic. Therefore, the olive biomass waste can be considered a potential adsorbent for the wastewater treatment with dyes, mainly.
Afficher plus [+] Moins [-]Suitability of four main Mediterranean tree crops for their growth in peri-urban agriculture and restoration (Gabes, Tunisia)
2021
Ben Amor, Afef | Bagues, Mohamed | Elloumi, Nada | Chaira, Nizar | Rahmani, Rami | Nagaz, Kamel
In order to increase the knowledge about crop tolerance to air pollutants in the different agroclimatic zones of the world, so that they can be efficiently considered for improving peri-urban agriculture, increasing the success of restoration projects, or enhancing air quality in polluted sites, the suitability of four economical valuable tree crops of the Mediterranean agriculture were studied under field conditions: date palm tree (Phoenix dactylifera L.), pomegranate (Punica granatum L.), fig tree (Ficus carica L.), and olive tree (Olea europaea L.). The measurement of biochemical markers such as ascorbic acid content, leaf relative water content, leaf total chlorophyll and leaf extract pH, at two contrasted air quality sites, a polluted site located around Gabes (Tunisia) industrial area and a control site, allowed the assessment of the air pollution tolerance index (APTI) and anticipated performance index (API) for the assayed species. Results showed obvious differences between the evergreen and the caducifolious tree crops assayed. Phoenix dactylifera tree (API = 6) was classified as an excellent performer for growing under poor air quality, followed by Olea europaea tree (API = 2) which was classified as a moderate performer. Both of trees can be recommended for successful results in peri-urban agriculture and restoration projects of polluted areas in the Mediterranean climate; on the contrary, the suitability of the Punica granatum (API = 1) was very poor, but still potentially interesting as a biological indicator of air pollution. Regarding the Ficus carica tree (API = 0), this species is not suitable for growing in air-polluted areas.
Afficher plus [+] Moins [-]Removal of Cu and Zn from Aqueous Solutions by Selected Tree Leaves with Phytoremediation Potential
2019
Massadeh, Adnan M. | Massadeh, Saif Addeen A.
In this study, some different selected plant leaves grown in Jordan such as Citrus limon (Rutaceae), Ceratonia siliqua L., Olea europaea (Oleaceae), Washingtonia filifera, and Myoporum (Myoporaceae) were examined for removal of copper (Cu) and zinc (Zn) ions from aqueous solutions. Cu and Zn were analyzed by atomic absorption spectrometry. A pH S-2 acidometer was used for determining the acidity of leaves solution system. Our findings showed the plants leaves were relatively efficient for removal of Cu and Zn compared to activated carbon. Removal of a 5 mg/L aqueous metal solution of Cu and Zn was treated with 2.5 g oven-dried plant in a 50 mL deionized water. The removal of Cu and Zn was expressed in terms of a time function ranged between 0 and 192 hours of contact time. The uptake of Cu and Zn by plant leaves was arranged in the following order:(i)Cu: Activated carbon > Washingtonia filifera > Ceratonia siliqua L. > Olea europaea (Oleaceae) > Myoporum (Myoporaceae) > Citrus limon (Rutaceae)(ii)Zn: Activated carbon > Olea europaea (Oleaceae) > Citrus limon (Rutaceae) > Ceratonia siliqua L. > Washingtonia filifera > Myoporum (Myoporaceae)
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