Search Results (66)

Electrically induced bearing failure is a reoccurring problem in modern drive train designs. To predict this damage, electrical models of bearings are required. In these models, the permittivity of lubricants is often assumed to be constant. However, the permittivity is dependent on pressure and temperature. For operating temperatures and pressures of journal bearings, no investigation of the permittivity of the lubricant exists. For this purpose, this study investigates the pressure and temperature dependence of lubricant permittivity using specially fabricated model bodies with layered structures of steel, ceramic insulating layers and copper in a parallel plate capacitor setup. Tests were performed applying temperatures between 20 °C and 100 °C and pressures between 1 and 250 bar. A mineral oil and a polyalkylene glycol (PAG) oil were examined. Results show a clear dependence of the permittivity on pressure and temperature. The mineral oil exhibits stronger pressure sensitivity, while the PAG oil shows more pronounced temperature dependence. Empirical equations to describe the permittivity as a function of temperature and pressure are derived. These findings provide relevant input for the selection of lubricants used in electrical environments. They also support the development of predictive models for modern electrical and tribological systems. Full article

Bacterial biofilms pose significant challenges in clinical, industrial, and environmental settings due to their inherent resistance to antimicrobial agents and host immune responses. Encased within a self-produced extracellular polymeric substance (EPS) matrix, these structured microbial communities demonstrate exceptional resilience, resisting conventional antimicrobial treatments and adapting to, as well as recovering from, environmental and therapeutic stresses, necessitating the development of novel anti-biofilm strategies. This review provides a comprehensive synthesis of biofilm formation, resistance mechanisms, and current and emerging approaches for controlling biofilms, with a primary focus on advancements made over the last decade. Chemical, physical, and biological strategies, including enzymatic degradation, natural compounds, chelating agents, nanoparticles, photodynamic therapy, and probiotics, have demonstrated promising antibiofilm activity. Additionally, combination therapies and targeted drug delivery systems have emerged as viable solutions to enhance the eradication of biofilms. Despite these advancements, challenges such as cytotoxicity, bacterial adaptation, and clinical applicability remain. Addressing these hurdles requires interdisciplinary research to refine existing strategies and develop innovative solutions for effective biofilm management. Full article

In recent years, herbal medicines (HMs) have been gaining significant attention as alternative or complementary therapeutic options. This is because synthetic drugs are expensive and have side effects, but also because herbal medicines have a rich content of effective bioactive compounds. These natural agents have been widely investigated for their potential in the prevention and management of chronic diseases including cardiovascular disorders, infections, metabolic disorders, neurological disorders, inflammatory disorders digestive diseases, oxidative stress-related diseases, and diabetes mellitus. In this review, we highlight the roles and impacts of various medicinal plants originating from diverse families, showing their bioactive characteristics, and the mechanisms through which they exert antidiabetic effects by regulating insulin secretion, oxidative stress, glucose uptake, and inflammatory pathways. In contrast to previous reviews, our study highlights the role of plants that are less explored, and integrates recent findings as well as future directions and biotechnological applications in plant-based management of diabetes. Full article

This research explores the dual role of biochar in addressing the escalating challenges of water salinity and pollution, focusing on its potential for both wastewater treatment and agricultural resilience. We investigated the adsorption capacity and efficiency of various biochar treatments to remove crystal violet dye from contaminated water. Biochar treated with H₂SO₄ demonstrated the highest adsorption capacity (450 mg/g). It consistently achieved 100% removal efficiency in all crystal violet concentrations tested, while silver-modified biochar showed a 99.95% removal rate at 50 ppm and an adsorption capacity of 5 mg/g. In agricultural applications, we evaluated the impact of biochar applications at concentrations of 1% and 3% on wheat crops irrigated with saline water of varying conductivity levels (0.63 and 10 dS/m). Wheat plants treated with 1% biochar exhibited the highest yield (26.6 cm) under 0.63 dS/m water conductivity, significantly outperforming the control group (17 cm). Biochar also resulted in elevated chlorophyll levels, with chlorophyll a ranging from 29.8 to 20.9 µg/mL and chlorophyll b ranging from 54 to 23 µg/mL, showing a marked improvement over the control. These findings demonstrate biochar’s potential to mitigate salinity-induced damage, with lower salinity conditions further enhancing chlorophyll a levels, while untreated plants showed reduced chlorophyll under high salinity. Full article

Gold nanoparticles (AuNPs) are promising materials for the development of novel anticancer agents, and their green synthesis has become essential because of their numerous advantages. This study aimed to synthesize AuNPs using an ethanolic extract of Scabiosa palaestina, characterize their physicochemical properties, and evaluate their anticancer properties and antioxidant potential. AuNPs were successfully synthesized and characterized using UV–visible spectroscopy, scanning electron microscopy (SEM), zeta potential analysis, thermogravimetric analysis (TGA), X-ray diffraction (XRD), and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). The results indicated that the biosynthesized AuNPs were spherical and well-dispersed, exhibiting an absorption peak at 560 nm and an average size of 9.9 nm. Cytotoxicity assays demonstrated dose- and time-dependent inhibitory effects on MDA-MB-231, Capan-2, HCT116, and 22Rv1 cancer cell lines, with 22Rv1 and MDA-MB-231 cells showing the most potent responses. At the highest concentration tested (100 µg/mL), after 72 h, cell viability was reduced to 16.04  ±  1.8% for 22Rv1 and 17.48  ±  8.3% for MDA-MB-231 cells. Additionally, the AuNPs exhibited concentration-dependent antioxidant activity in both 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide (H₂O₂) scavenging assays. In summary, the synthesized AuNPs demonstrated multifunctional properties that make them suitable for a wide range of biomedical and biotechnological applications. Full article

Breast cancer is a common and chronic condition, and despite improvements in diagnosis, treatment, and prevention, the number of cases of breast cancer is rising annually. New therapeutic drugs that target specific checkpoints should be created to fight breast cancer. Mandragora autumnalis possesses substantial cultural value as a herb and is regarded as one of the most significant medicinal plants; however, little is known about its anticancerous biological activity and chemopreventive molecular pathways against the triple-negative breast cancer (MDA-MB-231) cell line. In this study, the antioxidant, anticancer, and underlying molecular mechanisms of the Mandragora autumnalis ethanolic leaves extract (MAE) were evaluated, and its phytochemical composition was determined. Results indicated that MAE diminished the viability of MDA-MB-231 cells in a concentration- and time-dependent manner. Although MAE exhibited 55% radical scavenging activity at higher concentrations in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, the attenuation of its cytotoxic effects in MDA-MB-231 cells with N-acetylcysteine (NAC) co-treatment suggests a potential role of oxidative stress. Additionally, MAE caused an increase in the tumor suppressor p53. Moreover, this extract caused a significant decrease in the expression of Ki-67 (a cellular proliferation marker), MMP-9 (matrix metalloproteinase-9, an enzyme involved in extracellular matrix degradation and metastasis), and STAT-3 (a transcription factor regulating cell growth and survival). Also, MAE altered cell cycle, cell migration, angiogenesis, invasion, aggregation, and adhesion to suppress cellular processes linked to metastasis. All of our research points to MAE’s potential to function as an anticancer agent and opens up new possibilities for the development of innovative triple-negative breast cancer treatments. Full article

Background: One of the most widely used metal nanoparticles in biological applications is gold, which has unique physicochemical characteristics. Strong localized surface plasmon resonance (LSPR) endows them with exceptional optical properties that facilitate the development of innovative methods for biosensing, bioimaging, and cancer research, particularly in the context of photothermal and photodynamic therapy. Methods: This study marked the first time that Mandragora autumnalis ethanolic extract (MAE) was utilized in the environmentally friendly synthesis of gold nanoparticles (AuNPs). Several characterization methods, including dynamic light scattering analysis (DLS), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and biological methods, were used to emphasize the anti-cancerous activity of the biogenic AuNPs. Results: MAE-AuNPs showed a surface plasmon resonance band at 570 nm. DLS and SEM demonstrated the synthesis of small, spherical AuNPs with a zeta potential of −19.07 mV. The crystalline nature of the AuNPs was confirmed by the XRD pattern, and data from FTIR and TGA verified that MAE-AuNPs played a part in stabilizing and capping the produced AuNPs. In addition, the MAE-AuNPs demonstrated their potential effectiveness as antioxidant and anticancer therapeutic agents by demonstrating radical scavenging activity and anticancer activity against a number of human cancer cell lines, specifically triple-negative breast cancer cells. Conclusions: Green synthesis techniques are superior to other synthesis methods because they are simple, economical, energy-efficient, and biocompatible, which reduces the need for hazardous chemicals in the reduction process. This article highlights the significance of characterizing MAE-AuNPs and evaluating their antioxidant and anticancer properties. Full article

The escalating threats of climate change, pollution, and a rapidly growing global population are putting immense pressure on water resources, highlighting the urgent need for innovative wastewater recycling solutions. This study explores the potential of biochar, derived from common kitchen waste as a sustainable and efficient adsorbent for copper removal from contaminated water. Seven factors were studied for their influence on the adsorption process, including heavy metal concentration (50–250 ppm), biochar dosage (0.5–2.5 g), contact time (30 min to 29 h), temperature (20–80 °C), pH (2.67–8.07), and the efficacy of activated versus non-activated biochar, with activation carried out using phosphoric acid, silver nitrate, and sulfuric acid. Biochar characterization using Raman spectroscopy, specific surface area by Brunauer–Emmett–Teller analysis (BET), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Scanning Electron Microscopy—Energy Dispersive X-ray Spectroscopy (SEM-EDX), and zeta potential analysis revealed its robust adsorption capacity. Notably, silver nitrate-loaded biochar exhibited the highest adsorption capacity (24.44 mg/g) at 250 ppm of copper and the highest removal rate at about 99.3%, whereas phosphoric acid activation reduced this capacity to 5 mg/g due to structural damage. Importantly, biochar’s adsorption capacity was found to be pH-independent, simplifying operational requirements for treatment systems. Optimal conditions for maximum copper removal were determined to be 100 ppm of copper, a temperature of 60 °C, and a contact time of 30 min. The Langmuir isotherm model best described the adsorption process, indicating a monolayer adsorption with a maximum capacity of 23.25 mg/g. This comprehensive analysis underscores biochar’s potential as a cost-effective, efficient, and environmentally friendly solution for copper removal from wastewater. Full article

The toxicity of metals such as lead (Pb) and cadmium (Cd) makes heavy metal contamination in food products a major health concern. The aim of this study is to measure the levels of Pb and Cd in yogurt samples that were collected from 11 distinct Lebanese locations and determine their compliance with the legal limits set by the European Commission (0.02 mg/kg for Pb and 0.005 mg/kg for Cd). A total of 165 yogurt samples were examined using atomic absorption spectrophotometry (AAS). Interestingly, the findings showed that 10.9% of samples had Pb concentrations over the allowable limit; the highest amounts were observed in Baalbeck-Hermel (0.118 mg/kg), North Area (0.125 mg/kg), and South Lebanon (0.115 mg/kg). In addition, the highest detected concentrations of Cd were found in North Area (0.094 mg/kg), Baalbeck-Hermel (0.076 mg/kg), and Akkar (0.042 mg/kg), with 14.5% of samples above the limit. The results show regional differences in contamination, which are probably caused by industrial emissions, agricultural activities, and environmental pollution. To better understand the potential health implications, the estimated daily intake (EDI) of Pb and Cd through yogurt consumption was calculated and compared to international health-based guidance values. Although the EDI values suggest a low risk from yogurt alone, the findings highlight the importance of cumulative exposure and emphasize the necessity of regular monitoring and stricter implementation of food safety laws to decrease exposure to heavy metals through dairy intake. Full article

Bioprotection in winemaking refers to the use of naturally occurring microorganisms—mainly non-Saccharomyces yeasts—to inhibit the growth of spoilage microbes and reduce the need for chemical preservatives like sulfur dioxide (SO₂). Numerous studies have demonstrated the benefits of non-Saccharomyces as bioprotectants. However, the use of Saccharomyces cerevisiae as a bioprotectant has been studied very little. Furthermore, it can offer many advantages for the production of sulfite-free wines. To test if S. cerevisiae could be used in bioprotection, we compared the ability of different strains to inhibit the growth of Brettanomyces bruxellensis and Hanseniaspora uvarum. Among the strains tested, the S. cerevisiae Sc54 strain isolated from the vineyard of the Bekaa plain was selected. To investigate its mechanisms of action, we analyzed its metabolite production, including acetic acid and ethanol. Taking into account the low levels of these metabolites and the lack of similar inhibition patterns in media supplemented with acetic acid and ethanol, it appears that other factors contribute to its antagonistic properties. Nutrient competition was ruled out as a factor, as the growth inhibition of B. bruxellensis and H. uvarum occurred rapidly within the first 24 h of co-culture. In this study, we explored the role of the S. cerevisiae killer toxin (Sc54Kt) as a bioprotective agent against H. uvarum and B. bruxellensis spoilage yeasts. Purification procedures with ethanol allowed the extraction of Sc54Kt, yielding two concentrations (0.185 and 0.5 mg/mL). Remarkably, semi-purified Sc54Kt exhibited inhibitory effects at both concentrations under winemaking conditions, effectively controlling the growth and metabolic activity of the target spoilage yeasts. Overall, these findings demonstrate that S. cerevisiae Sc54 not only exerts a strong bioprotective effect but also contributes to improving the quality of wine. The results suggest that S. cerevisiae Sc54 is a promising bioprotective agent for mitigating spoilage yeasts in winemaking, offering a natural and effective alternative to conventional antimicrobial strategies. Full article

The spoilage of wine caused by Brettanomyces bruxellensis and Hanseniaspora uvarum poses a significant challenge for winemakers, necessitating the development of effective and reliable strategies to control the growth of these yeasts, such as grape must bioprotection. Despite evidence that certain microorganisms can inhibit the growth of Brettanomyces bruxellensis and Hanseniaspora uvarum, the specific mechanisms driving this inhibition remain unclear. The primary objective of this study is to elucidate the underlying mechanisms responsible for this inhibitory effect. We analyzed one Metschnikowia pulcherrima (Mp2) and two Lachancea thermotolerans (Lt29 and Lt45) strains, all of which demonstrated significant killing and inhibitory effects on Brettanomyces bruxellensis (B1 and B250) and Hanseniaspora uvarum (Hu3137) in synthetic must at pH 3.5 and 22 °C. The effectiveness of these two strains exhibited varying inhibition kinetics. The strains were monitored for growth and metabolite production (L-lactic acid, ethanol, and acetic acid) in both single and co-cultures. The low levels of these metabolites did not account for the observed bioprotective effect, indicating a different mechanism at play, especially given the different growth profiles observed with added L-lactic acid and ethanol compared to direct bioprotectant addition. Following the production, purification, and quantification of killer toxins, different concentrations of toxins were tested, showing that the semi-purified Mp2Kt, Lt29Kt, and Lt45Kt toxins controlled the growth of both spoilage yeasts in a dose-dependent manner. These bioprotectant strains also showed compatibility with Saccharomyces cerevisiae in co-cultures, suggesting their potential use alongside commercial starter cultures. Full article

This study examines the phytochemical composition, antioxidant, antifungal, and insecticidal properties of Origanum syriacum (Syrian oregano plant) and Cymbopogon wimterianus (Java citronella plant) extracts. Their potential applications in food preservation and pest control are explored based on their bioactive properties. The phytochemical screening indicated a rich presence of secondary metabolites in the extract. The hydrodistillation of plant leaves resulted in an extraction yield of 4.3% Syrian oregano essential oil. The major component of the essential oil was carvacrol (79.30%). The Syrian oregano ethanolic extract contained 110.674 ± 1.842 mg GAE/g total phenols and 52.57 ± 0.086 mg RE/g total flavonoids, and exhibited a high antioxidant activity with a half-maximal inhibitory concentration (IC₅₀) equal to 168.28 μg/mL. Flatbread was prepared with additions of Syrian oregano and Java citronella powders, followed by analysis of moisture content, visual appearance, and sensory characteristics. The results showed that the powders of Syrian oregano and Java citronella have promising food preservative effects. These findings were supported by a significant decrease in fungal growth in several samples and a shelf life extension of one day. The inclusion of a 2% mixture of Syrian oregano and Java citronella powder in the flatbread resulted in the sample receiving the highest overall acceptability mark from consumers, while also extending its shelf life. To assess the insecticidal activity, weevils (Sitophilus granarius L.) were exposed to Syrian oregano and Java citronella essential oils. The insecticidal activity was at its peak when Syrian oregano and Java citronella essential oils were combined resulting in 7% lethal dose (LD₅₀) towards grain weevils. Future research should focus on optimizing extraction methods, evaluating long-term storage effects, and assessing the broader applicability of these extracts in various food products and agricultural settings. Full article

In the Mediterranean and Himalayan regions, the genus Mandragora (family Solanaceae), sometimes called mandrake, is widely utilized in herbal therapy and is well-known for its mythical associations. Objective: To compile up-to-date information on M. autumnalis’s therapeutic properties. Its pharmacological properties and phytochemical composition are particularly covered in managing several illnesses, including diabetes, cancer, and heart disease. Methods: Articles on the review topic were found by searching major scientific literature databases, such as PubMed, Scopus, ScienceDirect, SciFinder, Chemical Abstracts, and Medicinal and Aromatic Plants Abstracts. Additionally, general online searches were conducted using Google Scholar and Google. The time frame for the search included items released from 1986 to 2023. Results:Mandragora has been shown to contain a variety of phytochemicals, including coumarins, withanolides, and alkaloids. The pharmacological characteristics of M. autumnalis, such as increasing macrophage anti-inflammatory activity, free radicals inhibition, bacterial and fungal growth inhibition, cytotoxic anticancer activities in vivo and in vitro against cancer cell lines, and enzyme-inhibitory properties, are attributed to these phytochemicals. Furthermore, M. autumnalis also inhibits cholinesterase, tyrosinase, α-amylase, α-glucosidase, and free radicals. On the other hand, metabolic risk factors, including the inhibition of diabetes-causing enzymes and obesity, have been treated using dried ripe berries. Conclusions: Investigations into the pharmacological and phytochemical characteristics of M. autumnalis have revealed that this plant is a rich reservoir of new bioactive substances. This review aims to provide insight into the botanical and ecological characteristics of Mandragora autumnalis, including a summary of its phytochemical components and antioxidant, antimicrobial, antidiabetic, anticancer, enzyme-inhibitory properties, as well as toxicological implications, where its low cytotoxic activity against the normal VERO cell line has been shown. More research on this plant is necessary to ensure its efficacy and safety. Still, it is also necessary to understand the molecular mechanism of action behind the observed effects to clarify its therapeutic potential. Full article

Various industrial activities release heavy metal ions into the environment, which represent one of the major toxic pollutants owing to their severe effects on the environment, humans, and all living species. Despite several technological advances and breakthroughs, wastewater treatment remains a critical global issue. Traditional techniques are dedicated to extracting heavy metal ions from diverse wastewater origins, encompassing coagulation/flocculation, precipitation, flotation, and ion exchange. Their cost, side toxicity, or ineffectiveness often limit their large-scale use. Due to their adaptable design, simple operation, and reasonable cost, membrane filtration and adsorption have proven their efficiency in removing metals from wastewater. Recently, adsorption-based filters have appeared promising in treating water. Within this range, filters incorporating natural, synthetic, or hybrid adsorbents present an appealing alternative to conventional approaches. This review aims to list and describe the conventional and advanced wastewater treatment methods by comparing their efficiency, cost, and environmental impact. Adsorption-based filters were highlighted due to the significant advantages they can provide. Full article

Plants are being researched as potential sources of novel drugs, which has led to a recent acceleration in the discovery of new bioactive compounds. Research on tissue culture technology for the synthesis and processing of plant compounds has skyrocketed, surpassing all expectations. These plants can be bought either raw or as extracts, where some of the chemicals are extracted by mashing the plant in water, alcohol, or another solvent. The use of herbal medicine may open new chances for reducing the onset of infections and treating different diseases including cancer. A perennial plant that blooms in the winter, Cyclamen, is one of the most widely used potted flowers in many nations. Alkaloids, flavonoids, phenols, tannins, saponins, sterols, and glycosides are the main active components of Cyclamen. Analgesic, cytotoxic, antioxidant, antimicrobial, and anti-inflammatory properties have all been demonstrated as potential effects of various extracts of Cyclamen tubers. However, the use of this medicinal plant in official medicine will require further research in the areas of pharmacology. Furthermore, it is necessary to create standard operating procedures for a crude herbal medication. In this regard, this review aims to highlight the key characteristics of the Cyclamen plant, such as its various parts, species, stages of development, and geographic range; pinpoint its intriguing bioactivities, its antioxidant, anti-inflammatory, and its anti-cancerous effects; and ascertain its potential medicinal uses and the main future perspectives. Full article