Hexosomes with Undecylenic Acid Efficient against Candida albicans

Enhancing antifungal and biocompatible efficacy of undecanoic acid through incorporation with chitosan-based nanoemulsion

The management of invasive fungal infections in humans poses significant challenges due to the intricate nature of the treatment, which is both arduous and costly, necessitating routine diagnostic procedures. Consequently, this investigation aimed to formulate a chitosan-based nanoemulsion (CS NEMs) incorporating the antifungal agent undecanoic acid (UDA), characterizing these NEMs and assessing their antifungal efficacy against both filamentous and non-filamentous fungal pathogens. The CS-based UDA NEMs were synthesized by introducing the surfactant Triton X-100 and the stabilizer glycerol. Nanoparticle tracking analysis (NTA) and SEM demonstrated the CS-UDA NEMs with an average size of 145 nm and 164.5 ± 24 nm, respectively. The successful formation of CS-UDA NEMs was verified through FTIR and XRD. CS-UDA NEMs exhibited exceptional inhibition against Aspergillus flavus, Aspergillus fumigatus, Aspergillus niger, and Candida albicans with MFC of 500, 500, 250 and 250 μg/mL, respectively. Additionally, CS-UDA NEMs displayed comparatively lower antioxidant activity as determined by DPPH and ABTS radical scavenging assays. Importantly, CS-UDA NEMs demonstrated no cytotoxic effects on NIH3T3 cells even at higher concentration (1000 μg/mL), as confirmed by cell viability and fluorescent staining assays. In conclusion, this study suggests that the developed CS-UDA NEMs hold promise as potent antifungal agents with diverse potential applications.

Lyotropic liquid crystalline 2D and 3D mesophases: Advanced materials for multifunctional anticancer nanosystems

Cancer remains a leading cause of mortality. Despite significant breakthroughs in conventional therapies, treatment is still far from ideal due to high toxicity in normal tissues and therapeutic inefficiency caused by short drug lifetime in the body and resistance mechanisms. Current research moves towards the development of multifunctional nanosystems for delivery of chemotherapeutic drugs, bioactives and/or radionuclides that can be combined with other therapeutic modalities, like gene therapy, or imaging to use in therapeutic screening and diagnosis. The preparation and characterization of Lyotropic Liquid Crystalline (LLC) mesophases self-assembled as 2D and 3D structures are addressed, with an emphasis on the unique properties of these nanoassemblies. A comprehensive review of LLC nanoassemblies is also presented, highlighting the most recent advances and their outstanding advantages as drug delivery systems, including tailoring strategies that can be used to overcome cancer challenges. Therapeutic agents loaded in LLC nanoassemblies offer qualitative and quantitative enhancements that are superior to conventional chemotherapy, particularly in terms of preferential accumulation at tumor sites and promoting enhanced cancer cell uptake, lowering tumor volume and weight, improving survival rates, and increasing the cytotoxicity of their loaded therapeutic agents. In terms of quantitative anticancer efficacy, loaded LLC nanoassemblies reduced the IC50 values from 1.4-fold against lung cancer cells to 125-fold against ovarian cancer cells.

Novel Formulation of Undecylenic Acid induces Tumor Cell Apoptosis

Undecylenic acid, a monounsaturated fatty acid, is currently in clinical use as a topical antifungal agent, however the potential for therapeutic application in other disease settings has not been investigated. In this study, we describe a novel platform for the solubilization of fatty acids using amino acids and utilize this approach to define a tumoricidal activity and underlying mechanism for undecylenic acid. We examined a novel formulation of undecylenic acid compounded with L-Arginine, called GS-1, that induced concentration-dependent tumor cell death, with undecylenic acid being the cytotoxic component. Further investigation revealed that GS-1-mediated cell death was caspase-dependent with a reduction in mitochondrial membrane potential, suggesting a pro-apoptotic mechanism of action. Additionally, GS-1 was found to localize intracellularly to lipid droplets. In contrast to previous studies where lipid droplets have been shown to be protective against fatty acid-induced cell death, we showed that lipid droplets could not protect against GS-1-induced cytotoxicity. We also found a role for Fatty Acid Transport Protein 2 (FATP2) in the uptake of this compound. Collectively, this study demonstrates that GS-1 has effective pro-apoptotic antitumor activity in vitro and, together with the novel platform of fatty acid solubilization, contributes to the re-emerging field of fatty acids as potential anti-cancer therapeutics.

Targeting foodborne pathogens via surface-functionalized nano-antimicrobials

The incorporation of antibiotics and bioactive compounds into non-toxic nanoparticles has been popularly used to produce effective antimicrobial nanocarriers against foodborne pathogens. These systems can protect antimicrobials against harsh environments, control their release, and increase their antimicrobial activities; however, their functions can be decreased by some major barriers. Intracellular localization of bacteria protects them from the host immune system and antimicrobial agents. Also, bacteria can cause constant infection by nestling in professional phagocytic cells. In the last years, surface functionalization of nanocarriers by passive and active modification methods has been applied for their protection against clearance from the blood, increasing both circulation time and uptake by target cells. For achieving this objective, different functional agents such as specifically targeted peptides internalize ligands, saccharide ligands, or even therapeutic molecules (e.g., antibodies or enzymes) are used. In this review, techniques for functionalizing the surface of antimicrobial-loaded nanocarriers have been described. This article offers a comprehensive review of the potential of functional nanoparticles to increase the performance of antimicrobials against foodborne pathogens through targeting delivery.

Lyotropic Liquid Crystalline Nanostructures as Drug Delivery Systems and Vaccine Platforms

Lyotropic liquid crystals result from the self-assembly process of amphiphilic molecules, such as lipids, into water, being organized in different mesophases. The non-lamellar formed mesophases, such as bicontinuous cubic (cubosomes) and inverse hexagonal (hexosomes), attract great scientific interest in the field of pharmaceutical nanotechnology. In the present review, an overview of the engineering and characterization of non-lamellar lyotropic liquid crystalline nanosystems (LLCN) is provided, focusing on their advantages as drug delivery nanocarriers and innovative vaccine platforms. It is described that non-lamellar LLCN can be utilized as drug delivery nanosystems, as well as for protein, peptide, and nucleic acid delivery. They exhibit major advantages, including stimuli-responsive properties for the “on demand” drug release delivery and the ability for controlled release by manipulating their internal conformation properties and their administration by different routes. Moreover, non-lamellar LLCN exhibit unique adjuvant properties to activate the immune system, being ideal for the development of novel vaccines. This review outlines the recent advances in lipid-based liquid crystalline technology and highlights the unique features of such systems, with a hopeful scope to contribute to the rational design of future nanosystems.

Topological defects in polycrystalline hexosomes from β-cyclodextrin fatty esters

Colloidal nanoparticles were prepared by aqueous self-assembly of amphiphilic β-cyclodextrins (βCDs) acylated on their secondary face with C₁₄ chains to a total degree of substitution of 7.0, via a thermolysin-catalyzed transesterification process. The small-angle X-ray scattering pattern of the nanoparticles was consistent with a reverse hexagonal organization. Cryo-transmission electron microscopy images revealed particles with spectacular tortuous shapes and consisting of misoriented domains with a regular columnar hexagonal structure, separated by sharp interfaces. Edge dislocations as well as a variety of stepped tilt grain boundaries (GBs) composed of symmetrical and asymmetrical sections, together with one twist GB, were identified from axial views of the columnar organization. The tilt GB structure was analyzed using the concepts of coincidence site lattice and structural units developed to describe the atomic structure of interfaces in various types of polycrystals. The tilt GBs were described using sequences of βCD-C₁₄ columns that differed by the number of neighboring columns (5, 6 or 7) and exhibiting distinctive contrasts. To our knowledge, this is the first time that these types of topological defects are described at the nanometric scale by direct observation of colloidal polycrystalline hexosomes of self-organized amphiphiles.

Osmium Nanoparticles-Polypropylene Hollow Fiber Membranes Applied in Redox Processes

Composite membranes play a very important role in the separation, concentration, and purification processes, but especially in membrane reactors and membrane bioreactors. The development of composite membranes has gained momentum especially through the involvement of various nanoparticles, polymeric, oxide, or metal, that have contributed to increasing their reactivity and selectivity. This paper presents the preparation and characterization of an active metal nanoparticle-support polymer type composite membrane, based on osmium nanoparticles obtained in situ on a polypropylene hollow fiber membrane. Osmium nanoparticles are generated from a solution of osmium tetroxide in tert-butyl alcohol by reduction with molecular hydrogen in a contactor with a polypropylene membrane. The composite osmium-polypropylene hollow fiber obtained membranes (Os-PPM) were characterized from the morphological and structural points of view: scanning electron microscopy (SEM), high resolution SEM (HR-SEM), energy dispersive spectroscopy analysis (EDAX), X-ray diffraction analysis (XRD), Fourier transform Infrared (FTIR) spectroscopy, thermal gravimetric analysis, and differential scanning calorimetry (TGA, DSC). The process performance was tested in a redox process of p-nitrophenol and 10-undecylenic (10-undecenoic) acid, as a target substance of biological or biomedical interest, in solutions of lower aliphatic alcohols in a membrane contactor with a prepared composite membrane. The characteristics of osmium nanoparticles-polypropylene hollow fiber membranes open the way to biological and biotechnological applications. These membranes do not contaminate the working environment, operate at relatively low temperatures, provide a large contact area between reactants, allow successive oxidation and reduction operations in the same module, and help to recover the reaction mass by ultrafiltration. The results obtained show that the osmium-polypropylene composite membrane allows the reduction of p-nitrophenol or the oxidation of 10-undecylenic acid, the conversion depending on the concentration in the lower aliphatic alcohol, the nature of the lower aliphatic alcohol, and the oxidant or reducing flow through the membrane contactor.

Bioimaging Applications of Non-Lamellar Liquid Crystalline Nanoparticles

Self-assembling processes of amphiphilic lipids in water give rise to complex architectures known as lyotropic liquid crystalline (LLC) phases. Particularly, bicontinuous cubic and hexagonal LLC phases can be dispersed in water forming colloidal nanoparticles respectively known as cubosomes and hexosomes. These non-lamellar LLC dispersions are of particular interest for pharmaceutical and biomedical applications as they are potentially non-toxic, chemically stable, and biocompatible, also allowing encapsulation of large amounts of drugs. Furthermore, conjugation of specific moieties enables their targeting, increasing therapeutic efficacies and reducing side effects by avoiding exposure of healthy tissues. In addition, as they can be easy loaded or functionalized with both hydrophobic and hydrophilic imaging probes, cubosomes and hexosomes can be used for the engineering of multifunctional/theranostic nanoplatforms. This review outlines recent advances in the applications of cubosomes and hexosomes for in vitro and in vivo bioimaging.

Reassessing the Use of Undecanoic Acid as a Therapeutic Strategy for Treating Fungal Infections

Treating fungal infections is challenging and frequently requires long-term courses of antifungal drugs. Considering the limited number of existing antifungal drugs, it is crucial to evaluate the possibility of repositioning drugs with antifungal properties and to revisit older antifungals for applications in combined therapy, which could widen the range of therapeutic possibilities. Undecanoic acid is a saturated medium-chain fatty acid with known antifungal effects; however, its antifungal properties have not been extensively explored. Recent advances indicate that the toxic effect of undecanoic acid involves modulation of fungal metabolism through its effects on the expression of fungal genes that are critical for virulence. Additionally, undecanoic acid is suitable for chemical modification and might be useful in synergic therapies. This review highlights the use of undecanoic acid in antifungal treatments, reinforcing its known activity against dermatophytes. Specifically, in Trichophyton rubrum, against which the activity of undecanoic acid has been most widely studied, undecanoic acid elicits profound effects on pivotal processes in the cell wall, membrane assembly, lipid metabolism, pathogenesis, and even mRNA processing. Considering the known antifungal activities and associated mechanisms of undecanoic acid, its potential use in combination therapy, and the ability to modify the parent compound structure, undecanoic acid shows promise as a novel therapeutic against fungal infections.

Efficient Synthesis of Cyclic Carbonates from Unsaturated Acids and Carbon Dioxide and their Application in the Synthesis of Biobased Polyurethanes

Bio-derived furan- and diacid-derived cyclic carbonates have been synthesized in high yields from terminal epoxides and CO₂ . Furthermore, four highly substituted terpene-derived cyclic carbonates were isolated in good yields with excellent diastereoselectivity in some cases. Eleven new cyclic carbonates derived from 10-undecenoic acid under mild reaction conditions were prepared, providing the corresponding carbonate products in excellent yields. The catalyst system also performed the conversion of an epoxidized fatty acid n-pentyl ester into a cyclic carbonate under relatively mild reaction conditions (80 °C, 20 bar, 24 h). This bis(cyclic carbonate) was obtained in high yields and with different cis/trans ratios depending on the co-catalyst used. An allyl alcohol by-product was only observed as a minor product when bis(triphenylphosphine)iminium chloride was used as co-catalyst. Finally, two cyclic carbonates were used as building blocks for the preparation of non-isocyanate poly(hydroxy)urethanes by reaction with 1,4-diaminobutane.

Nanosystems against candidiasis: a review of studies performed over the last two decades

The crescent number of cases of candidiasis and the increase in the number of infections developed by non-albicans species and by multi-resistant strains has taken the attention of the scientific community, which has been searching for new therapeutic alternatives. Among the alternatives found the use of nanosystems for delivery of drugs already commercialized and new biomolecules have grown, in order to increase stability, solubility, optimize efficiency and reduce adverse effects. In view of the growing number of studies involving technological alternatives for the treatment of candidiasis, the present review came with the intention of gathering studies from the last two decades that used nanotechnology for the treatment of candidiasis, as well as analysing them critically and pointing out the future perspectives for their application with this purpose. Different studies were considered for the development of this review, addressing nanosystems such as metallic nanoparticles, mesoporous silica nanoparticles, polymeric nanoparticles, liposomes, nanoemulsion, microemulsion, solid lipid nanoparticle, nanostructured lipid carrier, lipidic nanocapsules and liquid crystals; and different clinical presentations of candidiasis. As a general overview, nanotechnology has proven to be an important ally for the treatment against the diversity of candidiasis found in the clinic, whether in increasing the effectiveness of commercialized drugs and reducing their adverse effects, as well as allowing exploring more effectively properties therapeutics of new biomolecules.

Susceptibility to Medium-Chain Fatty Acids Is Associated with Trisomy of Chromosome 7 in Candida albicans

Aneuploidy (changes in chromosome number) and loss of heterozygosity (LOH) occur frequently in the human-pathogenic yeast Candida albicans and are associated with adaptation to stress and to antifungal drugs. Aneuploidy and LOH can also be induced during laboratory manipulations, such as during genetic transformation. We find that C. albicans strain SN152, commonly used to generate gene deletions, has undergone a major LOH event on chromosome 2. One deletion strain generated in this background has acquired extra copies of chromosomes 5 and 7. We find that trisomy (three copies) of chromosome 7 is associated with sensitivity to fatty acids.

Fatty acids have known antifungal effects and are used in over-the-counter topical treatments. Screening of a collection of gene knockouts in Candida albicans revealed that one strain, carrying a deletion of the transcription factor DAL81, is very susceptible to the medium-chain fatty acid undecanoic acid. However, reintroducing DAL81 does not restore resistance, and editing DAL81 in a different background does not introduce sensitivity. Whole-genome sequencing revealed that the C. albicansdal81Δ/Δ strain has an extra copy of chromosomes 5 and 7. Reversion to resistance to undecanoic acid was induced by growing the sensitive strain in yeast extract-peptone-dextrose with 60 μg/ml undecanoic acid for up to 9 days. Nine isolates that regained some resistance to undecanoic acid lost one copy of chromosome 7. The copy number of chromosome 5 does not appear to affect resistance to fatty acids. Moreover, the sensitivity may be related to having two copies of haplotype B of chromosome 7. In addition, we find that C. albicans strain SN152, used to delete DAL81 and many other genes, has undergone a major loss of heterozygosity event on chromosome 2 and a smaller one on chromosome 3.

IMPORTANCE Aneuploidy (changes in chromosome number) and loss of heterozygosity (LOH) occur frequently in the human-pathogenic yeast Candida albicans and are associated with adaptation to stress and to antifungal drugs. Aneuploidy and LOH can also be induced during laboratory manipulations, such as during genetic transformation. We find that C. albicans strain SN152, commonly used to generate gene deletions, has undergone a major LOH event on chromosome 2. One deletion strain generated in this background has acquired extra copies of chromosomes 5 and 7. We find that trisomy (three copies) of chromosome 7 is associated with sensitivity to fatty acids.

Synergistic Effect of Quinic Acid Derived From Syzygium cumini and Undecanoic Acid Against Candida spp. Biofilm and Virulence

In recent decades, fungal infections have incredibly increased with Candida genus as the major cause of morbidity and mortality in hospitalized and immunocompromised patients. Most of the Candida species are proficient in biofilm formation on implanted medical devices as well as human tissues. Biofilm related Candida infections are very difficult to treat using common antifungal agents owing to their increased drug resistance. To address these issues, the present study investigated the antibiofilm and antivirulent properties of Syzygium cumini derived quinic acid in combination with known antifungal compound undecanoic acid. Initially, antibiofilm potential of S. cumini leaf extract was assessed and the active principles were identified through gas chromatography and mass spectrometry analysis. Among the compounds identified, quinic acid was one of the major compounds. The interaction between quinic acid and undecanoic acid was found to be synergistic in the Fractional inhibitory concentration index (≤0.5). Results of in vitro assays and gene expression analysis suggested that the synergistic combinations of quinic acid and undecanoic acid significantly inhibited virulence traits of Candida spp. such as the biofilm formation, yeast-to-hyphal transition, extracellular polymeric substances production, filamentation, secreted hydrolases production and ergosterol biosynthesis. In addition, result of in vivo studies using Caenorhabditis elegans demonstrated the non-toxic nature of QA-UDA combination and antivirulence effect against Candida spp. For the first time, synergistic antivirulence ability of quinic acid and undecanoic acid was explored against Candida spp. Thus, results obtained from the present study suggest that combination of phytochemicals might be used an alternate therapeutic strategy for the prevention and treatment of biofilm associated Candida infection.