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Marine algae are renowned for their health benefits due to the presence of functional bioactive compounds. In this context, this study aims to valorize the extract of a seaweed, Dictyota dichotoma (D. dichotoma), through phytochemical characterization using liquid chromatography–mass spectrometry (HPLC-MS), as well as in vitro and in silico evaluation of its biological activities (antioxidant and antimicrobial). Phytochemical characterization revealed that the ethanolic extract of Dictyota dichotoma (DdEx) is rich in phenolic compounds, with a total of 22 phycocompounds identified. Antioxidant activity, measured by various methods, showed an IC50 of 120 µg/mL for the DPPH assay, an EC50 of 120.53 µg/mL for the FRAP assay, and a total antioxidant power of 685.26 µg AAE/mg according to the phosphomolybdate (TAC) method. Evaluation of antibacterial activity showed a zone of inhibition diameter ranging from 11.93 to 22.58 mm, with the largest zone observed for the Escherichia coli (E. coli) strain. For antifungal activity, inhibition zone diameters ranged from 22.38 to 23.52 mm, with the largest recorded for the Saccharomyces cerevisiae (S. cerevisiae) strain. The in silico study identified tetragalloyl-glucose, apigenin-7-O-glucoside, and pentagalloyl-glucose as the most active compounds against NADPH oxidase, with docking scores of −7.723, −7.424, and −6.402 kcal/mol, respectively. Regarding antibacterial activity, apigenin-7-O-glucoside, pelargonidin-3-O-glucoside, and secoisolariciresinol demonstrated high affinity for E. coli beta-ketoacyl-[acyl carrier protein] synthase, with docking scores of −7.276, −6.811, and −6.594 kcal/mol, respectively. These in vitro and in silico evaluations showed that D. dichotoma extract possesses antioxidant and antimicrobial properties, due to its richness in bioactive compounds identified by HPLC. [ABSTRACT FROM AUTHOR]

One of the main sources of novel chemicals with possible medical use is medicinal plants. Multiple diseases have been treated with them in traditional medicine. The purpose of this study was to explore the phytochemical characteristics, antioxidant effects, and antibacterial activities of several extracts of Ziziphus lotus fruits (ZLF). Phytochemical analysis of ZLF extracts revealed the presence of several bioactive molecules such as phenolic compounds and alkaloids. Water, methanol 50%, methanol 80%, methanol, ethanol, and hexane are the 6 different solvents which were used in order to evaluate the phytochemical profile as well as the biological activities of ZLF, and whose aqueous extract showed the best results. The aqueous extract had the highest yield, followed by methanol, ethanol, and lastly hexane (p < 0.05). The aqueous extract showed the highest total contents of phenols, flavonoids, and tannins (77.13 ± 0.11 mg GAE/g DM, 33.36 ± 0.51 mg QE/g DM, and 03.72 ± 0.16 mg CE/g DM respectively), while the Hexane extract revealed the lowest contents (12.36 ± 0.26 mg GAE/g DM, 06.20 ± 0.23 mg QE/g DM, and 01.20 ± 0.10 mg CE/g DM respectively). By using the DPPH, ABTS, and FRAP methods, and for the aqueous extract, ZLF extracts demonstrated considerable antioxidant capacities, with the values IC50 = 37 ± 0.27, IC50 = 67 ± 0.18 and IC0.5 = 31 ± 0.22 respectively. All of the ZLF extracts, with the exception of the hexanic extract on Staphylococcus aureus, showed antibacterial efficacy against the bacterial strains of Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The results obtained reveal that ZLF exhibit significant biochemical composition and considerable biological activities encouraging its nutritional and therapeutic use. [ABSTRACT FROM AUTHOR]

In the field of civil engineering, non-destructive methods occupy an essential place at the heart of each major project or planned civil engineering work. Among the several applications of this technique, one finds the quality control of various elements constituting the structure of the work (concrete, reinforcement, steel ... etc) as well as the recognition of pathologies. Of main interest in this context, non-destructive based methods allow for quality monitoring during construction and inspection of defects during and after the works, especially in inaccessible sites (piles, deep foundations, nuclear sites). Secondly, the preventive and corrective maintenance of old infrastructures can gain in efficiency thanks to the detection of failures and accurate localisation of damaged parts which are provided by this technique. It is in this perspective that the present research project focuses on the detection of failures that occur in deep foundations by means of a non-destructive testing method. A critical analysis is adopted and various methods were explored along with their principle, advantages, limitations and fields of application.

Ziziphus lotus has been the subject of several researchs because of its nutritional benefits and ecological attributes. The removal of hexavalent chromium Cr(VI) from a solution using powdered Zizphus lotus fruits, for its qualities of being inexpensive as well as environmentally friendly, was investigated. The results obtained showed that at pH = 2, at 30°C, after 600 min of adsorbent/adsorbate contact, with 100 mg/L as initial concentration of Cr(VI) and a biosorbent dosage of 5 g/L, the biosorption of Cr(VI) on Zizphus lotus fruit powder (ZLFP) is at its maximum rate. The sorption process was exothermic (H° = -6.69 kJ/mol), and was characterized by a positive entropy values (S° = 46.76 J/K mol) suggesting a high affinity of the ZLFP for Cr(VI). Given that the Gibbs free energy (G°) is negative and decreases as temperatures increase from 293 to 323 K, the process of biosorption is both feasible and spontaneous. The Temkin model and the Langmuir model both generated excellent fits to the equilibrium data. The maximum monolayer biosorption capacity was 36.11 mg/g. The pseudo second order model was used to fit the kinetic data relating to the adsorption of Cr(VI) on the ZLFP. The FTIR spectral analysis allowed the characterization of the biochemical groups mainly involved in the sorption of Cr(VI) ions on the ZLFP, and which are: N-C, H-O, O-C, H-C, and O=C. The capacity of Ziziphus lotus fruit as an inexpensive, effective, and ecofriendly biosorbent is confirmed through this study. [ABSTRACT FROM AUTHOR]

Paracetamol (PCT), or acetaminophen, is an important drug used worldwide for various clinical purposes. However, the excessive or indiscriminate use of PCT can provoke liver and kidney dysfunction; hence, it is essential to determine the amount of this target in biological samples. In this work, we develop a quick, simple, and sensitive voltammetric method using chemically modified electrodes to determine PCT in complex matrices, including human serum and commercial solid formulations. We modify the carbon paste electrode with stevensite monoclinic clay mineral (Stv-CPE), using cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy to characterise and detect PCT. The kinetics study provides a better electrochemical characterisation of the electrode behaviour, finding the detection and quantitation limits of 0.2 μM and 0.5 μM under favourable conditions. Further, the best linear working concentration range is 0.6–100 μM for PCT, applying the proposed method to the quantitative determination of PCT content in reference tablet formulations and biological samples for validation. [ABSTRACT FROM AUTHOR]

Ziziphus lotus is a wild plant that has recently become appreciated mainly due to the antioxidant and nutrient-rich properties of its fruits. The powder of the inedible leaves was investigated in this research in batch mode for its capacity to remove cadmium(II) and lead(II) ions as an ecofriendly and cost-effective biosorbent. Leaves powder revealed the highest uptake rate at pH = 8 and pH = 7 for Cd(II) and Pb(II), consecutively. The best metal adsorption rate is obtained with a temperature ranging from 25°C to 30°C, a contact time of 90 min, an initial ionic concentration of 100 mg/L, and a biosorbent dosage ranging from 3.5 to 5 g/L. The experimental kinetic data of the biosorption process for both heavy metal ions were fitted by the pseudo-second-order model. The equilibrium data fitted very well to the Langmuir model and Temkin model. The maximum monolayer biosorption capacities were 70.78 and 80.75 mg/g for Cd(II) and Pb(II), respectively. The main chemical groups which are involved in the trapping of Cd(II) and Pb(II) and which have been revealed by Fourier-transform infrared spectral analysis are: O-C, O=C, H-O, H-C, and N-C. The biosorption was endothermic (ΔH° = 7.33 kJ/mol for Cd(II), and 5.33 kJ/mol for Pb(II)). The reaction was accompanied by a decrease in entropy (ΔS° = -19.87 J/K·mol for Cd(II), and -8.38 J/K·mol for Pb(II)). When the temperature increases from 293 to 333 K, the Gibbs energy (ΔG°) increased, indicating that biosorption was less feasible at higher temperatures. The present research confirms that Z. lotus leaves could be exploited as a low-cost and an effective biosorbent for the elimination of Cd(II) and Pb(II) ions from aqueous solution. [ABSTRACT FROM AUTHOR]

The removal of cadmium (II) and lead (II) ions from aqueous solutions by the Ziziphus lotus fruits powder, as inexpensive and eco-friendly biosorbent, was studied in batch mode. Fruits powder (FP) revealed the highest uptake rate at pH=8 and pH=7 for Cd(II) and Pb(II) consecutively. The best metal adsorption rate is obtained with a temperature ranging from 25 to 30 °C, a contact time of 90 min, an initial ionic concentration of 100 mg/L, and a biosorbent dosage ranging from 3.5 to 5 g/L. The experimental kinetic data of the biosorption process for both heavy metal ions were fitted by the pseudo second order model. The equilibrium data fitted very well to the Langmuir model. The maximum monolayer biosorption capacities were 33.94 mg/g and 69.06 mg/g for Cd(II) and Pb(II) respectively. The main chemical groups which are involved in the trapping of Cd(II) and Pb(II) and which have been revealed by FTIR spectral analysis are: N-C, O=C, H-O, H-C, and O-C. The present research confirms that Z. lotus fruits could be exploited as a low-cost and an effective biosorbent for the elimination of Cd(II) and Pb(II) ions from aqueous solution. [ABSTRACT FROM AUTHOR]