Meryem Idrissi Yahyaoui

Supercritical carbon dioxide extraction (SFE-CO₂) is an efficient and environmentally friendly process for extracting bioactive compounds from plant material. This investigation examined the combined effects of air-drying temperature of the leaves and SFE-CO₂ operating conditions on the extraction yield, volatile compound composition, and antimicrobial activity of Pistacia lentiscus leaf extracts. Extractions were performed at pressures ranging from 100 to 200 bar and temperatures ranging from 35 to 55 °C. Extraction yield increased with extraction pressure and temperature, while fresh leaves yielded the highest extract, highlighting the importance of pretreatment on extractability. Chemical analysis revealed notable variations in monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, and oxygenated sesquiterpenes depending on drying temperature and extraction parameters, confirming the high sensitivity of the volatile compound composition to processing conditions. Response surface methodology (RSM) was used to optimize process variables in order to enhance antimicrobial activity. The extracts inhibited both bacterial and fungal strains, confirming that the extraction conditions exert a direct influence on biological properties. The quadratic model identified the optimal combinations of drying and supercritical CO₂ extraction parameters, thereby providing a rational strategy to maximize the antimicrobial potency of P. lentiscus extracts. Overall, controlling pretreatment and supercritical extraction conditions allows for targeted modulation of chemical composition and bioactivity, thereby promoting the development of natural antimicrobial agents and valuable functional components.

This study aimed to evaluate the biofunctional and selective anticancer potential of cell-free supernatants obtained from Lactiplantibacillus plantarum S61 fermented on two carbon sources: glucose (Glu) and xylooligosaccharides (XOS). High-performance liquid chromatography (HPLC) analysis revealed significant production of vitamin B2 (8.66 ± 0.11 and 8.05 ± 0.06 mg/L for Glc and XOS, respectively) and vitamin B12-like compounds (0.47 ± 0.03 and 0.24 ± 0.03 mg/L, respectively). The anti-inflammatory activity was assessed by inhibition of bovine serum albumin (BSA) denaturation, where XOS-fermented supernatants exhibited the strongest effect (88.7 ± 0.1% at 400 µg/mL), comparable to diclofenac (91.44 ± 0.1%), while Glc reached 71.1 ± 0.4%. The anticancer activity was evaluated in vitro using the MTT assay on two breast cancer cell lines (MCF-7 and MDA-MB-231) and normal peripheral blood mononuclear cells (PBMCs). Both fermented supernatants showed a dose-dependent cytotoxic effect against cancer cells while exhibiting markedly lower toxicity toward PBMCs, indicating a selective anticancer activity. XOS-fermented supernatants displayed lower IC₅₀ values against MCF-7 (198.55 ± 14.94 µg/mL) and MDA-MB-231 (200.80 ± 13.61 µg/mL) compared to PBMCs (862.16 ± 169.11 µg/mL), resulting in favorable selectivity index values. Overall, these findings highlight the potential of L. plantarum S61 postbiotic metabolites, particularly those derived from XOS fermentation, as safe and selective natural agents with anti-inflammatory and anticancer properties.

This study aimed to optimize a natural antifungal formulation comprising eucalyptol, β-pinene, and α-terpinene against Candida albicans, and Candida glabrata, two clinically relevant opportunistic fungal pathogens. These three monoterpenes, commonly found in essential oils of medicinal and aromatic plants, are recognized for their broad-spectrum antimicrobial properties, including notable antifungal activity. Prior to formulation studies, the physico-chemical profiles of the compounds were characterized, and an in silico toxicological assessment was conducted using predictive tools. All molecules were found to be safe, showing no potential for organ toxicity or adverse toxicological endpoints. An augmented simplex-centroid mixture design with three components was applied to evaluate twelve distinct formulations, enabling the analysis of compositional effects on antifungal efficacy, as determined by minimum inhibitory concentration (MIC) values. The results demonstrated that the antifungal activity was formulation-dependent. For C. albicans, the MIC was significantly influenced by the individual contribution of eucalyptol (σ₁) and its binary interaction with β-pinene (σ₁₂) (p < 0.05). In contrast, for C. glabrata, the individual effects of all three components (σ₁, σ₂, σ₃) and their ternary interaction (σ₁₂₃) were statistically significant (p < 0.05). The fitted models showed high predictive accuracy, with determination coefficients (R²) of 0.86 for C. albicans, and 0.96 for C. glabrata. Multi-response optimization using a desirability function identified formulations with MICs as low as 0.123% and 0.125% for C. albicans, and C. glabrata, respectively. The observed synergistic effects between components highlighted the enhanced antifungal potency of the mixtures over individual constituents. The optimal formulation effective against both species simultaneously comprised 22.26% eucalyptol, 42.90% β-pinene, and 34.82% α-terpinene, resulting in MICs of 0.290% and 0.301%, respectively. These findings support the potential of tailored essential oil-based mixtures as promising antifungal agents.

Multidrug-resistant (MDR) pathogens and biofilm-associated infections represent a major global health concern, particularly in the context of medical devices such as catheters, tubing, and blood sampling devices. Biofilms, responsible for up to 85% of human infections, confer a high level of microbial resistance and compromise device performance and patient safety. In this study, the antibiofilm potential of Syzygium aromaticum (clove) essential oil was investigated through an in vitro assay. GC–MS analysis revealed eugenol (72.77%) as the predominant compound, accompanied by β-caryophyllene (14.72%) and carvacrol (2.09%). The essential oil exhibited notable antimicrobial activity, producing inhibition zones of 30.5 ± 4.5 mm against Staphylococcus aureus, 24.5 ± 0.5 mm against Micrococcus luteus, 16.0 ± 2.0 mm against Escherichia coli, 13.0 ± 1.0 mm against Pseudomonas aeruginosa, 23.5 ± 1.5 mm against Candida albicans, and 24.0 ± 2.0 mm against C. glabrata. A marked reduction in biofilm biomass observed on polyvinyl chloride (PVC) surfaces. The application of clove essential oil as a coating for PVC-based medical devices remains a future possibility that requires formulation and in vivo testing. This strategy is proposed as potentially eco-safe, although environmental toxicity and biocompatibility have not yet been evaluated. It could contribute to the prevention of biofilm formation in arterial sampling systems and other healthcare-related materials, thereby enhancing device safety and longevity.

The optimization of bioactive compound mixtures is critical for enhancing pharmacological efficacy. This study investigates, for the first time, the combined effects of eugenol, camphor, and terpineol, focusing on their half-maximal inhibitory concentrations (IC₅₀) across multiple biological responses related to diabetes management. Using a mixture design approach, the objective was to determine the optimal formulation that maximizes bioactivity and validate the findings experimentally. A simplex-centroid design was applied to evaluate the combined effects of eugenol, camphor, and terpineol on AAI _IC50, AGI _IC50, LIP _IC50, and ALR _IC50 responses. The desirability function was used to determine the ideal composition. The optimized formulation was experimentally validated using in vitro assays, and IC50 values were measured for each response using standard protocols. Results: The optimal formulation identified was 44% eugenol, 0.19% camphor, and 37% terpineol, yielding IC₅₀ values of 10.38 µg/mL (AAI), 62.22 µg/mL (AGI), 3.42 µg/mL (LIP), and 49.58 µg/mL (ALR). The desirability score (0.99) confirmed the effectiveness of the optimized blend. Experimental validation of the optimal mixture resulted in IC₅₀ values of 11.02 µg/mL (AAI), 60.85 µg/mL (AGI), 3.75 µg/mL (LIP), and 50.12 µg/mL (ALR), showing less than 10% deviation from predicted values, indicating high model accuracy. This study confirms the combined potential of eugenol, camphor, and terpineol, with eugenol and terpineol significantly enhancing bioactivity. The validated formulation demonstrates potential for pharmaceutical and cosmeceutical applications. Future research should explore mechanistic interactions, bioavailability, and in vivo efficacy to support the development of optimized natural compound-based therapies.

This study aimed to characterize the fermentation of commercial xylooligosaccharide (XOS) using Lactiplantibacillus plantarum S61. XOS was utilized as the main carbon source in a modified MRS medium (MRSm) at concentrations of 1%, 2%, 4%, and 6% (w/v). The growth of L. plantarum S61 was tracked daily over a week and compared to a control MRS medium using glucose as the main carbon source. The pH, total free acidity, and biomass were analyzed during fermentation, and the resulting fermentation product was analyzed for its content of fatty acids, total polyphenols, and the production of antioxidant and antimicrobial metabolites. The findings revealed that L. plantarum S61 thrived in MRSm, particularly at a 6% XOS concentration, which was identified as the best condition among the four tested concentrations (1%, 2%, 4%, and 6%). The fermentation of XOS by L. plantarum S61 significantly increased the total phenolic content and antioxidant activity compared to glucose, with the highest phenolic content observed at 6% XOS (6.70 ± 0.01 mg GAE/g). The strains produced various organic acids including lactic, malic, and oxalic acids from glucose and XOS. Notably, the strains yielded a broader range of organic acids with higher contents in the presence of XOS, leading to enhanced antifungal and antibacterial activities compared to glucose. Significant antibacterial activity was observed against Gram-negative bacteria, particularly Salmonella enterica, with inhibition zones of 20.25 mm and 11.75 mm for XOS (5% and 6%) and glucose, respectively. For Gram-positive bacteria, S. aureus and M. luteus exhibited inhibition zones of 20.01 mm for XOS 6% and 10.25 mm for glucose. In terms of antifungal activity, the strongest inhibition was observed against Rhodotorula glutinis, with inhibition zones of 26.00 mm for XOS 6% and 20.04 mm for glucose. The fermentation product of XOS by L. plantarum S61 showed significant inhibitory effects against pathogenic bacteria and yeasts, suggesting its potential application in the manufacturing of preservatives with antifungal properties and pharmaceutical products targeting pathogenic and spoilage yeasts.

This article presents a new method for preparing multifunctional composite biomaterials with applications in advanced biomedical fields. The biomaterials consist of dicalcium phosphate (DCPD) and bioactive silicate glasses (SiO₂/Na₂O and SiO₂/K₂O), containing the antibiotic streptomycin sulfate. Materials were deeply characterized by X-ray diffraction and attenuated total reflectance Fourier transform infrared spectroscopy, and zeta potential analysis, UV–visible spectrophotometry, and ion-exchange measurement were applied in a simulating body fluid (SBF) solution. The main results include an in situ chemical transformation of dicalcium phosphate into an apatitic phase under the influence of silicate solutions and the incorporation of the antibiotic. The zeta potential showed a decrease in surface charge from ζ = −24.6 mV to ζ = −16.5 mV. In addition, a controlled and prolonged release of antibiotics was observed over a period of 37 days, with a released concentration of up to 755 ppm. Toxicity tests in mice demonstrated good tolerance of the biomaterials, with no significant adverse effects. Moreover, these biomaterials have shown potent antibacterial activity against various bacterial strains, including Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, suggesting their potential use in tissue engineering, drug delivery, and orthopedic and dental implants. By integrating the antibiotic into the biomaterial composites, we achieved controlled release and prolonged antibacterial efficacy. This research contributes to advancing biomaterials by exploring innovative synthetic routes and showcasing their promise in regenerative medicine and controlled drug delivery.

This study focused on developing an innovative, straightforward, and economical method utilizing a mixture of readily available solvents to extract arborescin (C₂OH₂OO₈) crystals from Artemisia absinthium L. (A. absinthium). The structural elucidation and characterization were conducted using a suite of techniques including IR spectroscopy, CNHSO elemental analysis, scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDS), and mass spectroscopy (MS). Density functional theory (DFT) calculations were employed to determine the molecular properties. Antioxidant activity was measured using the DPPH radical scavenging assay and the β-carotene bleaching test. Antimicrobial efficacy was assessed against four bacterial strains and three fungal strains. The molecular docking approach was employed to predict the probable binding patterns and affinities of arborescin with specific target biomolecules. Employing an array of analytical techniques, examination of the isolated crystal from A. absinthium. led to its comprehensive structural elucidation. IR spectroscopy revealed the presence of distinctive functional groups, including a carbonyl group within the γ-lactone and an epoxy group. CNHSO elemental analysis verified that the crystal contained only carbon, hydrogen, and oxygen, a finding corroborated by SEM-EDS analysis, consistent with the molecular structure of arborescin. Additionally, mass spectrometry confirmed the identity of the compound as arborescin, with a molecular ion with a mass m/z = 248. Quantum-Chemical Descriptors revealed that arborescin is resistant to elementary decomposition under standard conditions. Although arborescin demonstrates a relatively low antioxidant capacity, with an IC50 of 5.04 ± 0.12 mg/mL in the DPPH assay, its antioxidant activity in the β-carotene bleaching test was found to be 3.64%. Remarkably, arborescin effectively inhibits the growth of Staphylococcus aureus and Listeria innocua at low concentrations (MIC = 166 µg/mL). Additionally, it exhibits significant antifungal activity against Candida glabrata, with a minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of 83 µg/mL and 166 µg/mL, respectively. In this study, arborescin exhibited a robust docking score of −8.1 kcal/mol, indicating a higher affinity compared to ciprofloxacin. This suggests that arborescin has significant potential as a potent antibacterial agent.

This paper presents a novel cheminformatics approach for the design and synthesis of hydroxyapatite/collagen nanocomposites, which have potential biomedical applications in tissue engineering, drug delivery, and orthopedic and dental implants. The nanocomposites are synthesized by the co-precipitation method with different ratios of hydroxyapatite and collagen. Their mechanical, biological, and degradation properties are analyzed using various experimental and computational techniques. Attenuated total reflection–Fourier-transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction unveil the low crystallinity and nanoscale particle size of hydroxyapatite (22.62 nm) and hydroxyapatite/collagen composites (14.81 nm). These findings are substantiated by scanning electron microscopy with energy-dispersive X-ray spectroscopy, confirming the Ca/P ratio between 1.65 and 1.53 and attesting to the formation of non-stoichiometric apatites in all samples, further validated by molecular simulation. The antimicrobial activity of the nanocomposites is evaluated in vitro against several bacterial and fungal strains, demonstrating their medical potential. Additionally, in silico analyses are performed to predict the absorption, distribution, metabolism, and excretion properties and the bioavailability of the collagen samples. This study paves the way for the development of novel biomaterials using chemoinformatics tools and methods, facilitating the optimization of design and synthesis parameters, as well as the prediction of biological outcomes. Future research directions should encompass the investigation of in vivo biocompatibility and bioactivity of the nanocomposites, while exploring further applications and functionalities of these innovative materials.