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The rapid expansion of agriculture in the Souss Massa region has been accompanied by a significant increase in pesticide usage to protect and increase crop yields. Unfortunately, these pesticides leave behind residues that can have detrimental effects on both human health and the environment. To investigate the impact of pesticide contamination on the coasts of Agadir Bay, our study focuses on the bivalve Perna perna (Linnaeus, 1758) as a biomonitoring sentinel species. Between autumn 2009 and summer 2010, we conducted measurements of pesticide residue concentrations and assessed two biomarkers of pollution the Glutathion-S-transferase (GST) and acetylcholinesterase (AChE) in the soft tissues of P. perna. These bivalves were seasonally collected from two different locations along the Agadir Bay coast. The results revealed that Glutathion-S-transferase and acetylcholinesterase showed seasonal variations, likely influenced by the species' reproductive cycle. In terms of pesticide concentrations, the levels of organochlorines were found to range from 13.40 to 109.76 ng g−1 of dry weight (dw) for Dichlofluanide, not-detected (ND) to 38.66 ng g−1 dw for Endosulfan S, ND to 15.76 ng g−1 dw for Lindane, ND to 33.66 ng g−1 dw for Fenarimol, and 0.26–35.02 ng g−1 dw for Buperimate. It should be noted that these levels of pesticide contamination are relatively low compared to values reported in similar studies conducted in other regions of the world. The contamination of Agadir Bay by pesticides can be attributed to their extensive use in agricultural practices in the Souss Massa region. [ABSTRACT FROM AUTHOR]

This investigation focuses on the elaboration of undoped zinc oxide (ZnO) thin films and ZnO thin films doped with 6% of nickel (Ni), cobalt (Co), and iron (Fe). The fabrication process employed the Successive Ionic Layer Adsorption and Reaction (SILAR) method, involving 30 SILAR cycles, and annealing at 400 °C in an oxygen-rich environment. Structural analysis via X-ray diffraction (XRD) revealed a hexagonal wurtzite structure characteristic of ZnO. No secondary phases associated with Ni, Fe, or Co were identified. The incorporation of dopants led to decreased crystallinity, indicated by a reduction in XRD peak intensities and a change in preferred orientation. Optical characterization unveiled a red shift in the transmittance spectra of doped ZnO thin films, signifying a reduction in the bandgap energy when compared to undoped ZnO. This reduction holds promise for augmenting photocatalytic performance and enhancing electrical conductivity in practical applications. Morphological investigations showed modifications in grain size and distribution within the doped samples, aligning with the structural observations. Energy-dispersive X-ray (EDX) analysis confirmed the successful integration of dopant atoms into the ZnO lattice. Electrical measurements confirmed that all doped ZnO samples exhibited n-type semiconductor behavior, characterized by lowered resistivity, increased mobility, and carrier concentration relative to undoped ZnO. These enhancements can be attributed to the introduction of additional electrons by the dopants. This comprehensive examination offers valuable insights into the structural, optical, and electrical characteristics of doped ZnO thin films, providing a promising route for their integration into optoelectronic and energy conversion devices. [ABSTRACT FROM AUTHOR]

In the present study, the antibacterial activity of Thymus leptobotrys and Thymus satureioïdes essential oils was evaluated against nine multidrug resistant Acinetobacter baumannii strains. Besides, their inhibition and eradication effects were investigated, for the first time, against the biofilm form of the tested multidrug resistant bacteria. Gas chromatography–mass spectrometry analysis of the targeted essential oils highlighted the predominance of carvacrol and borneol, respectively. Their antibacterial activity test revealed considerable inhibition zones' diameters (p < 0.05), ranging from 35 ± 1.4 to 43.6 ± 0.5 mm (Thymus leptobotrys) and from 16.6 ± 1.5 to 22 ± 2.8 mm (Thymus satureioïdes). Very low minimal inhibitory and bactericidal concentrations (p < 0.05) were also noted, varying from 0.78 to 12.5 mg/mL. Four strains out of nine (Acinetobacter baumannii 6, Acinetobacter baumannii 7, Acinetobacter baumannii 8, Acinetobacter baumannii 9) considered as the strongest biofilm producers by congo red agar and crystal violet methods, were chosen for the evaluation of biofilm inhibition and eradication effects of Thymus leptobotrys and Thymus satureioïdes essential oils. Great biofilm inhibition percentages were noted with 90.20% (Thymus satureioïdes) and 97.27% (Thymus leptobotrys) as the highest rates. Forty-eight hours biofilms were more resistant to the essential oils' action. Low eradication proportions were observed ranging from 0 to 49%. Thus, Thymus leptobotrys and Thymus satureioïdes essential oils could be considered as a natural source of bioactive molecules and used as an alternative approach to prevent biofilm formation of multidrug resistant Acinetobacter baumannii. [ABSTRACT FROM AUTHOR]

In Morocco, the marine environment has always been a major occupation for socioeconomic activities (industry, tourism, urbanization, etc.). Thus, this work displays a case study of Taghazout coast in the central Atlantic part of the country, which becomes the center of several development projects, such as the touristic resort Taghazout Bay. In the aim to assess the health status of this coastal ecosystem, a multi-indicator approach based on the response of biomarkers in the wedge clam Donax trunculus was adopted during two years (2016/2017). The undertaken investigations on the response of biomarkers (AChE, GST, MDA, and CAT) in the sentinel species D. trunculus showed an activation of defense mechanisms in this bivalve, which would imply exposure to chemical stress in this ecosystem. The monitoring of seasonal bioaccumulation of cadmium (Cd), lead (Pb), and copper (Cu) by D. trunculus indicates that the bivalves collected have been exposed to these metal sources in the study area. In addition, the correlation study has reported a significant effect of environmental parameters on biomarker response. Overall, the multi-indicator approach has clearly revealed the health status of Taghazout coast registered in a coastal urbanization. [ABSTRACT FROM AUTHOR]

The aim of the present study is the first to evaluate the ecotoxic state of the marine environment in Anza-Taghazout coasts (Morocco) after installation of two wastewater treatment plants using a natural population of marine bivalves Mytilus galloprovincialis. These coasts are exposed to many discharges generating, thus, different sources of pollutants. These pollutants can modulate the physiological responses of marine bivalves to environmental stress. In this context, a multibiomarker approach consisting of a battery of biomarker evaluation was used to assess the response of these species to stress. In the whole soft tissues of M. galloprovincialis, four biomarkers were evaluated as follows: acetylcholinesterase (AChE), glutathione S-transferase (GST), catalase (Cat), and malondialdehyde activity (MDA). In parallel, physico-chemical parameters were measured in the marine water of Anza-Taghazout within three selected sites: S1 considered as "hotspot" located at Anza city; S2 located near of Aourir city; and the third site, S3 "reference" located in Imouran beach. Our results showed that activities of both glutathione S-transferase and catalase were higher in M. galloprovincialis collected from site S1, but high values of malondialdehyde and acetylcholinesterase activities were observed successively at S3 and S2. Application of integrated biomarker response (IBR) index was suitable for classifying the stress response in the M. galloprovincialis but did not allow to evaluate the level of the xenobiotic exposure in the studied sites. The statistical results did not show any significant differences between the three studied sites, and therefore, S1 has recently become clean due to the installation of two wastewater treatment plants. [ABSTRACT FROM AUTHOR]

Background: Agadir city plans to reuse treated wastewater on a large scale to irrigate these green spaces. This study aims to evaluate the risk of intestinal parasites, to which human and animal populations are exposed during the reuse of treated wastewaters. Methods: Over 21 months, wastewater samples were collected in Bensergao and Mzar wastewater treatment plants, in Agadir city, southern Morocco. The occurrences and removal of intestinal parasites were inspected using the modified Bailenger method. Results: The biodiversity of helminths is higher than protozoa, while the protozoa cysts are more abundant and more prevalent. Generally, the highest parasitic loads were recorded during the hot season. For raw waters, the average concentration of protozoa cysts was 173.33 ± 70.81 cysts per L for Bensergao plant and 179.33 ± 129.22 cysts per L for Mzar plant. However, the helminths average concentration was 48.70 ± 39.91 eggs/larvae per L for Bensergao plant and 51.10 ± 31.76 eggs/larvae per L for Mzar plant. The purified water of the Mzar plant does not contain parasites, unlike the Bensergao plant where a small numbers of parasites were detected, included 2.33 ± 1.53 cysts per L for protozoa and 0.45 ± 0.58 eggs/larvae per L for helminths. Conclusions: Considering parasitological risks, the purified waters of Bensergao plant cannot be used without risks to the public health and environment. In contrast, the purified waters and the purified waters disinfected by ultraviolet radiation from the Mzar plant can be used safely to water the green spaces of Agadir city. [ABSTRACT FROM AUTHOR]

In order to use purified wastewater on watering green spaces of Agadir city, we conducted this study to assess the bacteriological and physicochemical quality of treated wastewater in Mzar treatment plant. To realize these objectives, we analyzed four types of waters: raw water (RW), decanted water, purified water and purified water treated by the ultraviolet radiation (PWUV). The biologically analyzed parameters are fecal coliforms (FC) and fecal enterococci (FE). The physicochemical parameters are: pH, electrical conductivity, chemical oxygen demand (COD), five-day biological oxygen demand (BOD5) and total suspended solids (TSS). The results showed a high level of bacterial contamination in all types of waters, and the average loads of FC were between 4.71 × 106 CFU/100 mL (RW) and 1.45 × 103 CFU/100 mL (PWUV), while loads of FE were between 2.62 × 105 CFU/100 mL (RW) and 7.92 CFU/100 mL (PWUV). The physicochemical parameters show a pH close to neutrality and a high electrical conductivity (3261 μS/cm) in PWUV. In all stages of wastewater treatment, values of COD, BOD5 and TSS were under the limit values recommended by Moroccan standards. Except for the electrical conductivity and FC, all the studied parameters were under the limit values requested by the Moroccan standards. The microbiological quality of PWUV is unstable, and if these waters are reused, they can affect the microbiological and physicochemical quality of green spaces and groundwater. [ABSTRACT FROM AUTHOR]