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Water resources are vital for life, yet they are exposed to various risks. In the estern Rif of Morocco, the Oued Kert is a crucial water resource for a large population. Therefore, evaluating their health status is essential to ensure their optimal preservation. In this context, five stations (S1, S2, S3, S4, and S5) were monitored, during the four campaigns (September, December, March, and June 2022), to assess the physicochemical quality of water. In this sense, seven parameters were measured, temperature, pH, electrical conductivity (EC), Biochemical oxygen demand (BOD5), Chemical oxygen demand (COD), nitrates, and ammonium. In addition, an evaluation of metal contamination was conducted during a single campaign (May 2022) by measuring four elements (Al, Fe, Li, and Mn). The levels of electrical conductivity (greater than 3000 μS cm-1), and COD (greater than 40mg L-1 in S2, S3, and S4) indicate poor water quality, while, the average concentrations of ammonium classify these waters as of moderate quality. The results of metal contamination revealed the presence of iron (Fe) at a concentration of 1.9 mg L-1 in S5, classifying these waters as of moderate quality according to Moroccan water quality standards.

The measurement uncertainty (MU) in environmental analyses is usually considered as a combination of the additive contributions from sampling, sample preparation and analytical measurement (usually instrumental). The target MU for such studies is usually relatively high due to the natural sample heterogeneity and/or the complicated pretreatment procedure required. In the analytical practice, the contribution of the sample preparation to MU is rarely evaluated. Thus, it remains a hidden part of the one related to the analysis. However, the knowledge for the contribution of sample preparation might provide important information and further possibility for optimization of the entire analytical procedure and reduction of the expanded MU of the analytical result. From statistical point of view, the separation of uncertainty contributions from the different steps is, generally, not a trivial task. Selection of the proper statistical approach depends on the data structure and quality, variables distribution, etc. In the present study, three different statistical methods for evaluation of the uncertainty contribution of the sample preparation were applied, compared, and discussed. The considered approaches are based on, both, classical and robust analysis of variances (ANOVA) applied to data from instrumental analysis of marine algae and bee honey samples, undergoing microwave digestion. Some general recommendations on the statistical approach selection are revealed based on real experimental data set. [ABSTRACT FROM AUTHOR]

A total of fourteen honey samples, including monofloral, polyfloral, and honeydew honeys, collected from Bulgaria, Turkiye, and Morocco were analyzed with the aim to investigate the influence of floral origin on the biological properties of honey. The antioxidant activities of the samples were estimated using the DPPH, ABTS, FRAP, and CUPRAC methods, as well as analyzing their phytochemical composition by measuring the total phenolic content through the Folin- Ciocalteu method and individual polyphenols by HPLC. The results demonstrated that honeydew honey exhibited the highest total phenolic content and antioxidant activity among all the samples tested. It was followed by linden and forest honeys, which also demonstrated significant biological activity. In contrast, acacia and ziziphus honeys displayed the lowest levels of phenolic content and antioxidant properties among the samples. Our results indicated that while the botanical origin of honey had a significant influence on its biological properties, other factors such as geographical location also played a role in determining its quality. The observed variations among the honey samples from the same botanical origin could be attributed to factors such as specific landscape conditions, including whether the honey was sourced from an urban or rural area, the timing of harvest, beekeeping practices, and storage conditions. [ABSTRACT FROM AUTHOR]

Boldine ((S)-2,9-dihydroxy-1,10-dimethoxy-aporphine) has been defined as the major alkaloid in Chilean boldo tree. Besides its diverse pharmacological activities, e.g. neuroprotective, cytoprotective, anti-inflammatory activities, boldine also exhibits tyrosinase-inhibiting effect. Tyrosinase [EC 1.14.18.1] is well known as a bifunctional enzyme that is responsible for the melanin biosynthesis. Considering the diphenolic structural feature of the alkaloid, which is associated with its tyrosinase inhibitory properties, herein we first modified the boldine core and then linked it with the natural phenolic antioxidants such as: caffeic-, ferulic- and sinapic acids. Furthermore, the newly amides were tested in vitro on the mushroom tyrosinase. Our results indicated, that amongst the tested boldine derivatives, caffeoyl- and feruloylamides have shown the anti-tyrosinase activity closely correlated with a hydroquinone, used as a standard. [ABSTRACT FROM AUTHOR]

Mineral composition of Nigella S. seed variety having Moroccan origin, was determined. The methodology consisted in Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) determination after microwave assisted digestion. The accuracy of the procedure was assured by recovery studies of Nigella seeds samples spiked at different concentration levels. The results revealed that potassium was a predominate element, followed by calcium and magnesium. According to the microelements Moroccan black cumin seeds were good source of iron, zinc and aluminum. A comparative study has indicated variations in mineral content among black cumin seeds with different geographical origin. [ABSTRACT FROM AUTHOR]

Pollution by heavy metals is one of the most serious issues in the world, and the principal sources are manufacturing, fertilizers, mining, pesticides, transport, and wastewater discharge. In this study, the presence of macroelements (Nitrogen (N) and Phosphorus (P)) and heavy metals (Chromium (Cr), Nickel (Ni), Cadmium (Cd), Iron (Fe), Zinc (Zn), Lead (Pb), Cooper (Cu), and Manganese (Mn)) in the green tide caused by the green seaweed Ulva lactuca from Marchica lagoon (NE-Morocco, Mediterranean) was evaluated. The mean values of P and N in the algae were 1773.33 mg·kg −1 and 44.4 g·kg −1, respectively. The heavy metals have mean values following this descending sequence: Fe > Mn > Zn > Cu > Ni > Pb > Cr > Cd. This finding has suggested that Ulva has the strongest affinity to Fe and Mn among the metals examined. Mn, Fe, and Pb recorded the highest bioconcentration factors (BCFs), which were 1687, 1656, and 1643, respectively. Regarding their contribution to the Recommended Dietary Allowance (RDA), Fe showed a contribution of 13.58% to the RDA, while that of Mn varied between 4.42 % and 28.42%. The health risk assessment did not indicate any hazard related to the ingestion of Ulva lactuca. Therefore, this study suggests that Ulva lactuca in the Nador lagoon has the potential to bioaccumulate heavy metals and mitigate eutrophication. [ABSTRACT FROM AUTHOR]

In this study two silica gel sorbents with different mobilization agents were applied for solid phase extraction of palladium(II) from 0.1 mol L-1 - 3 mol L-1aqueous HCl solution. The first sorbent was prepared by immobilization of 4 - aminoantypyrine Schiff base (Schiff B-4-AAP) and the second one - by introduction of S-containing amino acid analog, N-benzyloxycarbonyl-L-methionine (Z-Met-OH) on the silica gel surface through physical adsorption. Thus, the obtained two silica sorbents were functionalized with nitrogen (Sig ~ Schiff B-4-AAP) and nitrogen and sulfur (Sig ~ Z-Met-OH) chelating groups. The role of various chemical parameters was studied for quantitative sorption of Pd(II) through batch adsorption experiments. It was found that the extraction efficiency of the newly prepared sorbents toward Pd(II) depends on the concentration of HCl in the sample solution and the contact time between Pd ions and the sorbents as well as on the type and concentration of the eluent. The optimal acid concentration for quantitative adsorption of Pd(II) was 1 mol L-1 HCl. The experiments showed that the coexisting ions - base metals exhibited little interference on the Pd(II) separation. [ABSTRACT FROM AUTHOR]

Schiff bases of 4-aminoantipyrine (Fig. 1, (a-d)) are synthesized and immobilized on silica gel to obtain 4 sorbents selective for Pt ions (Sig-Schiff a-d). The extraction efficiency of the newly prepared sorbents toward Pt(II) and Pt(IV) is studied by a batch method and the application was performed in a column mode. The role of various parameters such as the sample acidity, the type and the concentration of the eluent, the sample and the eluent flow rates are optimized for a quantitative sorption of Pt(II) and Pt(IV). The influence of the different substituents in the benzylidene ring of the Schiff bases on the coordination properties of the sorbents and the extraction efficiency and selectivity toward Pt species is elucidated. It is found that the sorbents synthesized demonstrate a high selectivity toward Pt(II) - the quantitative sorption is achieved at high concentrations of HCl, whereas Pt(IV) has a poor sorption ability under identical experimental conditions. Moreover, the sorbents preserve their extraction capability and selectivity toward Pt(II) in acidic media even in presence of significant amounts of base metals. An analytical procedure is developed for Pt determination in surface waters and spent automotive catalysts. [ABSTRACT FROM AUTHOR]

A series of 4-(substituted benzylidene-amino)-2,3-dimethyl-1-phenyl- 3-pyrazoline-5-ones (3a-l) was obtained using sonochemical assisted reaction. The synthesized Schiff bases were evaluated for their antiviral, antibacterial, anticandida, DPPH scavenging and anti-tyrosinase activities in vitro. The antimicrobial screening results revealed that amongst the tested imines, compound 3l appeared to be а promising one (with a minimal inhibitory concentration 47 ug/ml). The most potent DPPH scavengers were azometines 3a and 3g. No significant inhibition on the monophenolase activity in vitro of mushroom tyrosinase was observed. [ABSTRACT FROM AUTHOR]

Currently, there is an increasing interest towards α-glucosidase inhibition of various diseases including diabetes mellitus type 2, cancer, HIV, and B- and C-type viral hepatitis. Cinnamic acid derivatives have been shown to be potentially valuable as a new group of α-glucosidase inhibitors. Therefore, herein, the α-glucosidase inhibitory activity of trans-N-cinnamoyl and hydroxycinnamoyl amides was studied in vitro. Results revealed that the tested hydroxycinnamoyl amides (1–16) inhibited a-glucosidase with IC50s ranging between 0.76 and 355.1 μg/ml. Compounds 1, 2, 5, 6, 9, 14, and 15 showed significant inhibition of yeast α-glucosidase, being even more potent ones than the used positive inhibitor acarbose (IC50=2.50±0.21 μg/ml). [ABSTRACT FROM AUTHOR]

The concentration levels of heavy and toxic elements circulating in the environment increase due to various industrial activities. Now it is well understood that the environmental particles influence directly the cloud properties and atmosphere visibility, and indirectly change the global climate. Particles with aerodynamic diameter larger than approx. 10 µm were collected by Bergerhoff's method around metallurgical works "Kremicovtzi" in Sofia, Bulgaria. Samples of atmospheric particles smaller than approx. 10 µm were collected by filter technique from the meteorological stations Milesovka and Kopisty, located in a highly polluted industrial region of the Czech Republic. Inductively coupled plasma atomic emission spectrometry (ICP-AES) was applied in this study for quantitative determination of traces of elements after sample extraction with aqua regia according to ISO 11466:1995. The accuracy is ensured by the following ICP-AES methodology: (a) quantification of spectral interferences in the presence of Al, Ca, Mg, Fe and Ti as a complex environmental matrix around the prominent lines of the analytes, and (b) line selection for trace analysis. The content of some pollutants (As, Ba, Cu, Mn, Pb, Zn, Al, Ca, Mg, Fe and Ti) was compared to the corresponding threshold concentration levels and to the results from the chemical analysis of hundreds of individual particles by using Electron Probe X-ray Micro-Analyses (EPXMA). [ABSTRACT FROM AUTHOR]