Search Results (27)

Background/Objectives: Candidiasis, an opportunistic fungal infection caused by Candida species, is a major health problem, particularly in immunocompromised individuals. Increasing resistance of yeasts such as Candida spp. to pharmacological antifungal agents makes it necessary to explore alternative treatments. The aim of this study was to evaluate the antifungal potential of Gomortega keule essential oil (GKEO) against Candida spp. by assessing growth and development at 24 and 48 h. Encapsulation and characterization of a stable nanoemulsion were carried out to enhance efficacy. Methods: The anti-yeast activity of both free GKEO and the nanoemulsion against Candida albicans, C. glabrata, and C. guilliermondii was evaluated using a microdilution method to determine the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) at 24 and 48 h. Results: GC-MS/MS analysis identified forty-one components in GKEO, the main ones being eucalyptol (21.41%), 4-terpineol (19.62%), and α-terpinyl acetate (13.89%). Antifungal assays revealed that both free and nanoemulsion-formulated GKEO inhibited the growth of all tested Candida strains. At 48 h, the nanoformulated GKEO achieved a MIC value of 32 µg/mL and an MFC of 64 µg/mL for C. albicans and C. glabrata and showed higher antifungal activity compared to the free oil, in particular against C. albicans, exhibiting a four-fold lower MFC value. The activity of the nanoformulation was comparable to or better than fluconazole against C. glabrata and C. guilliermondii. Conclusions: The GKEO nanoemulsion potentiated anti-yeast activity against Candida spp. The formulation improved the efficacy of GKEO, suggesting its potential as an alternative or adjunctive treatment for candidiasis. Full article

The incidence of fungal infections is significantly rising, posing a challenge due to the limited class of antifungal drugs. There is a necessity to combat emerging resistant fungal infections by developing novel antifungal agents. This study aimed to evaluate the antifungal effects of lawsone (LAW), a natural component extracted from herbal medicine, and LAW-loaded mesoporous silica nanoparticles (LAW-MSNs) on growth, biofilm formation, and expression of ALS1 and EPA1 genes contributing to cell adhesion of Candida spp. Twenty C. albicans and twenty C. glabrata isolates, including ten fluconazole-resistant and ten fluconazole-susceptible isolates, were examined. The findings of the study indicated that LAW and LAW-MSNs inhibited Candida isolates growth at MIC range of 0.31–>5 µg/mL and significantly reduced biofilm formation in C. albicans and C. glabrata. Moreover, both LAW and LAW-MSNs downregulated the expression of the adhesion genes ALS1 and EPA1 in C. albicans and C. glabrata. Based on the obtained findings, LAW emerged as a promising antifungal candidate. However, the nano-formulation (LAW-MSNs) improved its antifungal properties. Full article

Background/Objectives: Filamentous fungi, in particular the species Aspergillus, Scedosporium, and Exophiala, frequently colonize the lungs of cystic fibrosis (CF) patients. Chronic colonization is linked to hypersensitivity reactions and persistent infections leading to a significant long-term decline in lung function. Azole antifungal therapy such as voriconazole (VRC) slows disease progression, particularly in patients with advanced CF; however, excessive mucus production in CF lungs poses a diffusional barrier to effective treatment. Methods: Here, biodegradable nanohydrogels (NHGs) recently developed as nanocarriers were evaluated for formulating VRC as a platform for treating fungal infections in CF lungs. The NHGs entrapped up to about 30 μg/mg of VRC, and physicochemical properties were investigated via dynamic laser light scattering and nanoparticle tracking analysis. Diameters were 100–400 nm, and excellent colloidal stability was demonstrated in interstitial fluids, indicating potential for pulmonary delivery. Nano-formulations exhibited high in vitro cytocompatibility in A549 and HEK293T cells and were tested for the release of VRC under two different sink conditions. Results: Notably, the antifungal activity of VRC-loaded nanohydrogels was up to eight-fold greater than an aqueous suspension drug against different fungal species isolated from CF sputum, regardless of the presence of a CF artificial mucus layer. Conclusions: These findings support the development of potent VRC nano-formulations for treating fungal disorders in CF lungs. Full article

Biofilms are complex microbial communities encased within a self-produced extracellular matrix, which plays a critical role in chronic infections and antimicrobial resistance. These enhance pathogen survival and virulence by protecting against host immune defenses and conventional antimicrobial treatments, posing substantial challenges in clinical contexts such as device-associated infections and chronic wounds. Secondary metabolites derived from medicinal plants, such as alkaloids, tannins, flavonoids, phenolic acids, and essential oils, have gained attention as promising agents against biofilm formation, microbial virulence, and antibiotic resistance. These natural compounds not only limit microbial growth and biofilm development but also disrupt communication between bacteria, known as quorum sensing, which reduces their ability to cause disease. Through progress in nanotechnology, various nanocarriers such as lipid-based systems, polymeric nanoparticles, and metal nanoparticles have been developed to improve the solubility, stability, and cellular uptake of phytochemicals. In addition, the synergistic use of plant-based metabolites with conventional antibiotics or antifungal drugs has shown promise in tackling drug-resistant microorganisms and revitalizing existing drugs. This review comprehensively discusses the efficacy of pure secondary metabolites from medicinal plants, both as individuals and in nanoformulated forms or in combination with antimicrobial agents, as alternative strategies to control biofilm-forming pathogens. The molecular mechanisms underlying their antibiofilm and antivirulence activities are discussed in detail. Lastly, the current pitfalls, limitations, and emerging directions in translating these natural compounds into clinical applications are critically evaluated. Full article

Background/Objectives: Natural products are gaining increasing importance due to the large variety of biological activities exerted by their constituents. Among these, the products deriving from Acmella oleracea (L.) R.K. Jansen can be exploited for their local anaesthetic, myorelaxant, anti-inflammatory/analgesic, and antifungal properties. In this regard, there is a need to develop novel formulations for the topical delivery of A. oleracea-derived extracts to widen their use in the pharmaceutical and cosmetic fields. Methods: Nanoformulations, i.e., nanoemulsions (NEs) and microemulsions (MEs), were investigated as a strategy to encapsulate an extract from A. oleracea at the nanoscale level in water and then incorporated into xanthan gum-based hydrogels. Results: Only NEs provided a physically stable formulation, while the precipitation of solid hydrophobic components from the extract was observed during ME preparation under all tested conditions despite the use of ethyl oleate as an oily co-solvent. The optimized NE-based hydrogel remained physically stable over six months, as confirmed by rheological measurements and polarized optical microscope observation, without a phase separation phenomenon. Therefore, NEs resulted more suitable nanodispersed systems than MEs for the encapsulation of A. oleracea extract, which contains a large amount of hydrophobic constituents that are solid at room temperature. Furthermore, the sustained spilanthol release across an artificial membrane (Franz cell apparatus) and the cytotoxic profile on HaCaT cell line support its potential topical application. Conclusions: The outcomes of this study provided valuable insights into the formulation of A. oleracea extract, broadening its fields of applicability, including topical administration. Full article

Essential oils (EOs) are known for their diverse bioactivities, including antioxidant, anti-inflammatory, antibacterial, antifungal, antiviral, skin-barrier repairing and anticancer, and therefore, hold profound potential to be used in cosmetic and skincare products. Owing to these properties, EOs have long been utilized to address a range of dermatological issues, from acne and inflammation to aging and dryness. However, problems associated with EOs beset their practical applications, which include high volatility, oxidation, hydrophobic nature, low bioavailability, skin irritation, chemical transformation and poor stability in air and light. A prospective of nanolipidic formulations, including the nanostructured lipid carriers (NLCs) and solid lipid nanoparticles (SLNs) system for improved skin delivery of these EOs highlights the possibility of their use in topical applications, which offer several advantages such as improved bioavailability and stability, lower toxicity and higher drug content. These nanoformulations protect the EOs from environmental degradation and improve their penetration into deeper skin layers, leading to prolonged therapeutic benefits. The delivery of bioactive agents using a conventional topical preparation exhibits low penetration, frequent applications, poor adherence and prolonged therapy duration, whereas the novel delivery system exhibits improved stability of the drug, enhanced skin penetration, enhanced retention and better therapeutic efficacy. This review provides a comprehensive compendium of information on EOs, which are widely used in skincare, along with their nanolipidic formulations for maximized skincare uses. The mechanism of action of EOs as skin bioactive agents, challenges associated with their use, advances in nanolipidic formulations and their market value as cosmetic skincare products are also explored. Full article

Natamycin is a tetraene polyene that exploits its antifungal properties by irreversibly binding components of fungal cell walls, blocking the growth of infections. However, topical ocular treatments with natamycin require frequent application due to the low ability of this molecule to permeate the ocular membrane. This limitation has limited the use of natamycin as an antimycotic drug, despite it being one of the most powerful known antimycotic agents. In this work, different lipidic nanoformulations consisting of transethosomes or lipid nanoparticles containing natamycin are proposed as carriers for optical topical administration. Size, stability and zeta potential were characterized via dynamic light scattering, the supramolecular structure was investigated via small- and wide-angle X-ray scattering and 1H-NMR, and the encapsulation efficiencies of the four proposed formulations were determined via HPLC-DAD. Full article

Nanotechnology presents promising opportunities for enhancing pest management strategies, particularly in protecting active ingredients to prolong their shelf life and effectiveness. Among different approaches, the combination of inorganic nanoparticles with active ingredients such as the main constituents of natural essential oils in one nanoarchitecture is challenging. In this study, hydrophobic calcium hydroxide nanoparticles coated with oleylamime [Ca(OH)₂@OAm NPs] were synthesized using microwave-assisted synthesis. These primary NPs were physicochemically characterized and subsequently utilized to prepare nanocapsules (NCs) either alone (Ca NCs) and/or in combination with geraniol at different ratios of Ca(OH)₂@OAm NPs and geraniol, i.e. 1:1 (CaGer1 NCs), 1:2 (CaGer2 NCs), and 1:3 (CaGer3 NCs), respectively. Among the formulations, the CaGer2 NCs demonstrated higher encapsulation efficiency (EE) and loading capacity (LC) of 95% and 20%, correspondingly. They exhibited a hydrodynamic size of 306 nm, a ζ-potential of −35 mV, and a monodisperse distribution. Release kinetics of geraniol from CaGer2 NCs indicated a pH-dependent slow release over 96 h at both 25 °C and 35 °C. In vitro antifungal assay against B. cinerea revealed a concentration-dependent activity, and the EC₅₀ values for Ca(OH)₂@OAm NPs, Ca NCs, and CaGer2 NCs were estimated to be 654 µg/mL, 395 µg/mL, and 507 µg/mL, respectively. These results underscore the potential of Ca-based nanoformulations to control plant pathogens, suggesting that while Ca NCs showcase potent antifungal attributes, the different architectures/structures play a critical role in the antifungal effectiveness of the nanoformulations that have to be explored further. Full article

Flavonoids are hydroxylated phenolic substances in vegetables, fruits, flowers, seeds, wine, tea, nuts, propolis, and honey. They belong to a versatile category of natural polyphenolic compounds. Their biological function depends on various factors such as their chemical structure, degree of hydroxylation, degree of polymerization conjugation, and substitutions. Flavonoids have gained considerable attention among researchers, as they show a wide range of pharmacological activities, including coronary heart disease prevention, antioxidative, hepatoprotective, anti-inflammatory, free-radical scavenging, anticancer, and anti-atherosclerotic activities. Plants synthesize flavonoid compounds in response to pathogen attacks, and these compounds exhibit potent antimicrobial (antibacterial, antifungal, and antiviral) activity against a wide range of pathogenic microorganisms. However, certain antibacterial flavonoids have the ability to selectively target the cell wall of bacteria and inhibit virulence factors, including biofilm formation. Moreover, some flavonoids are known to reverse antibiotic resistance and enhance the efficacy of existing antibiotic drugs. However, due to their poor solubility in water, flavonoids have limited oral bioavailability. They are quickly metabolized in the gastrointestinal region, which limits their ability to prevent and treat various disorders. The integration of flavonoids into nanomedicine constitutes a viable strategy for achieving efficient cutaneous delivery owing to their favorable encapsulation capacity and diminished toxicity. The utilization of nanoparticles or nanoformulations facilitates drug delivery by targeting the drug to the specific site of action and exhibits excellent physicochemical stability. Full article

Inorganic-based nanoparticle formulations of bioactive compounds are a promising nanoscale application that allow agrochemicals to be entrapped and/or encapsulated, enabling gradual and targeted delivery of their active ingredients. In this context, hydrophobic ZnO@OAm nanorods (NRs) were firstly synthesized and characterized via physicochemical techniques and then encapsulated within the biodegradable and biocompatible sodium dodecyl sulfate (SDS), either separately (ZnO NCs) or in combination with geraniol in the effective ratios of 1:1 (ZnOGer1 NCs), 1:2 (ZnOGer2 NCs), and 1:3 (ZnOGer2 NCs), respectively. The mean hydrodynamic size, polydispersity index (PDI), and ζ-potential of the nanocapsules were determined at different pH values. The efficiency of encapsulation (EE, %) and loading capacity (LC, %) of NCs were also determined. Pharmacokinetics of ZnOGer1 NCs and ZnOGer2 NCs showed a sustainable release profile of geraniol over 96 h and a higher stability at 25 ± 0.5 °C rather than at 35 ± 0.5 °C. ZnOGer1 NCs, ZnOGer2 NCs and ZnO NCs were evaluated in vitro against B. cinerea, and EC₅₀ values were calculated at 176 μg/mL, 150 μg/mL, and > 500 μg/mL, respectively. Subsequently, ZnOGer1 NCs and ZnOGer2 NCs were tested by foliar application on B. cinerea-inoculated tomato and cucumber plants, showing a significant reduction of disease severity. The foliar application of both NCs resulted in more effective inhibition of the pathogen in the infected cucumber plants as compared to the treatment with the chemical fungicide Luna Sensation SC. In contrast, tomato plants treated with ZnOGer2 NCs demonstrated a better inhibition of the disease as compared to the treatment with ZnOGer1 NCs and Luna. None of the treatments caused phytotoxic effects. These results support the potential for the use of the specific NCs as plant protection agents against B. cinerea in agriculture as an effective alternative to synthetic fungicides. Full article

This article reports on incorporating magnetic nanoparticles into natural carbon frameworks derived from Nigella Sativa seeds and their synthesis via co-precipitation reactions for application in biomedicine. The magnetic Nigella Sativa Seeds (Magnetic NSS), a metal oxide-based bio-nanomaterial, has shown excellent water diaper presence due to the presence of a wide range of oxygenous hydroxyl and carboxyl groups. The physicochemical properties of the composites were characterized extensively using Fourier transform infrared spectroscopy (FTIR), powder-X-ray diffraction (XRD), scanning electron microscopy (SEM), elemental analysis, transmission electron microscopy (TEM), and vibrating-sample magnetometer. Furthermore, synthesized magnetic NSS showed antioxidant and antifungal activity. The antifungal susceptibility was further tested against Candida albicans with a MIC value of 3.125 µg/mL. Analysis of antioxidant defense enzymes was determined quantitatively; the results suggested that antioxidant enzyme activity increase with increased magnetic NSS concentration. Furthermore, biofilm inhibition assay from scanning electron microscopy results revealed that magnetic NSS at the concentration of 3.5 μg/mL has anti-biofilm properties and can disrupt membrane integrity. Full article

Dermatomycosis is a common fungal infection, and its treatment is limited by few antifungal agents. Clioquinol (CQ) is an antiparasitic agent that has been studied for new uses, such as antifungal and antiviral applications. CQ was incorporated into a lipid-based nanocarrier as a new, promising option for dermatomycosis. This study aimed to develop a CQ-loaded lipid-based nanocarrier for cutaneous application and to evaluate its antifungal activity. CQ-loaded nanoformulation (LBN-CQ) was developed using the ultrasonication method, and the particle size, polydispersity index (PDI), pH, zeta potential, and drug content were monitored for 45 days. To evaluate antifungal activity, broth microdilution and a time-kill assay were performed. LBN-CQ presented a particle size of 91 ± 3 nm and PDI of 0.102 ± 0.009. The zeta potential and pH values were −9.7 ± 2.0 mV and 6.0 ± 0.1, respectively. The drug content was 96.4 ± 2.3%, and the encapsulation efficiency was 98.4%. LBN-CQ was able to reduce the minimum inhibitory concentration (MIC) in a 2-fold or 4-fold manner in most of the tested strains. Additionally, LBN-CQ presented stable fungistatic action that was not concentration- or time-dependent. In conclusion, the developed CQ-loaded nanocarrier is a promising treatment for skin fungal infections and a promising candidate for future randomized clinical trials. Full article

Background: Candida auris represents an emerging pathogen that results in nosocomial infections and is considered a serious global health problem. The aim of this work was to evaluate the in vitro antifungal efficacy of Cinnamomum cassia essential oil (CC-EO) pure or formulated in polycaprolactone (PCL) nanoparticles against ten clinical strains of C. auris. Methods: nanoparticles of PCL were produced using CC-EO (nano-CC-EO) and cinnamaldehyde (CIN) through the nanoprecipitation method. The chemical profile of both CC-EO and nano-CC-EO was evaluated using SPME sampling followed by GC-MS analysis. Micro-broth dilution tests were performed to evaluate both fungistatic and fungicidal effectiveness of CC-EO and CIN, pure and nano-formulated. Furthermore, checkerboard tests to evaluate the synergistic action of CC-EO or nano-CC-EO with micafungin or fluconazole were conducted. Finally, the biofilm disrupting activity of both formulations was evaluated. Results: GC-MS analysis shows a different composition between CC-EO and nano-CC-EO. Moreover, the microbiological analyses do not show any variation in antifungal effectiveness either towards the planktonic form (MIC_CC-EO = 0.01 ± 0.01 and MIC_nano-CC-EO = 0.02 ± 0.01) or the biofilm form. No synergistic activity with the antifungal drugs tested was found. Conclusions: both CC-EO and nano-CC-EO show the same antimicrobial effectiveness and are potential assets in the fight against C. auris. Full article

Curcumin or turmeric is the active constituent of Curcuma longa L. It has marvelous medicinal applications in many diseases. When the skin integrity is compromised due to either acute or chronic wounds, the body initiates several steps leading to tissue healing and skin barrier function restoration. Curcumin has very strong antibacterial and antifungal activities with powerful wound healing ability owing to its antioxidant activity. Nevertheless, its poor oral bioavailability, low water solubility and rapid metabolism limit its medical use. Tailoring suitable drug delivery systems for carrying curcumin improves its pharmaceutical and pharmacological effects. This review summarizes the most recent reported curcumin-loaded delivery systems for wound healing purposes, chiefly hydrogels, films, wafers, and sponges. In addition, curcumin nanoformulations such as nanohydrogels, nanoparticles and nanofibers are also presented, which offer better solubility, bioavailability, and sustained release to augment curcumin wound healing effects through stimulating the different healing phases by the aid of the small carrier. Full article

Fungal diseases are a significant cause of morbidity and mortality worldwide, primarily affecting immunocompromised patients. Aspergillus, Pneumocystis, and Cryptococcus are opportunistic fungi and may cause severe lung disease. They can develop mechanisms to evade the host immune system and colonize or cause lung disease. Current fungal infection treatments constitute a few classes of antifungal drugs with significant fungi resistance development. Amphotericin B (AmB) has a broad-spectrum antifungal effect with a low incidence of resistance. However, AmB is a highly lipophilic antifungal with low solubility and permeability and is unstable in light, heat, and oxygen. Due to the difficulty of achieving adequate concentrations of AmB in the lung by intravenous administration and seeking to minimize adverse effects, nebulized AmB has been used. The pulmonary pathway has advantages such as its rapid onset of action, low metabolic activity at the site of action, ability to avoid first-pass hepatic metabolism, lower risk of adverse effects, and thin thickness of the alveolar epithelium. This paper presented different strategies for pulmonary AmB delivery, detailing the potential of nanoformulation and hoping to foster research in the field. Our finds indicate that despite an optimistic scenario for the pulmonary formulation of AmB based on the encouraging results discussed here, there is still no product registration on the FDA nor any clinical trial undergoing ClinicalTrial.gov. Full article