Eugenol-acacia gum-based bifunctional nanofibers as a potent antifungal transdermal substitute

Biochemical insights into synergistic Candida biofilm disintegrating ability of p-cymene inclusion complex and miconazole

Phytoactive molecules emerge as a plentiful reservoir of adjuvant and antifungal agents. The resolution of solubility and stability issues has been facilitated by developing molecular complexes or inclusion complexes of phytoactive molecules. Miconazole (MCZ) is a favoured azole with low off-target impact, however, its pharmacological efficacy requires a revamp to enhance its suitability as an antifungal drug. Hence, the present investigation delves into the mechanism of action of the p-cymene/β-cyclodextrin inclusion complex (IC) along with MCZ against Candida albicans and Candidaglabrata biofilms. The synergy between IC and MCZ has been estimated at a concentration of 6.25 μg/mL IC + 0.5 μg/mL MCZ with a FICI of 0.19. The prepared IC + MCZ displayed remarkable antifungal properties against planktonic and sessile growth of Candida species. IC + MCZ exhibited a notable 80% biofilm eradication potential against both species, corroborated by morphological analysis using FE-SEM. The results indicated that IC/IC + MCZ acts by disrupting the biochemical composition of the ECM, altering the surface properties of the cells, reducing ergosterol, enhancing membrane permeability, and inducing oxidative stress. In conclusion, the study highlighted the synergistic antibiofilm activity of p-cymene IC with miconazole against Candida species. In summary, IC + MCZ has been established as a potent antifouling agent against Candida species, warranting further exploration for potential formulation with additional investigations.

Natural products in the treatment of diabetic foot infection

Diabetic foot infections (DFIs) are a significant complication in diabetes mellitus, leading to increased morbidity, hospitalizations, and healthcare burdens. The growing prevalence of antibiotic-resistant pathogens has reduced the efficacy of conventional treatments, highlighting the need for alternative therapeutic strategies. Natural products, known for their antimicrobial, anti-inflammatory, and wound-healing properties, have garnered attention as potential treatments for DFIs. This review examines key natural compounds, including eugenol, thymol, carvacrol, curcumin, and Aloe vera, and their mechanisms of action in combating diabetic infections. We analyze the antimicrobial efficacy of these compounds, their ability to inhibit biofilm formation, and their role in wound healing. The review also explores challenges in integrating natural products into clinical practice and the potential for their use alongside or in place of traditional antibiotic therapies. Our findings suggest that natural products could play a crucial role in developing sustainable and effective treatment strategies for DFIs, especially in the face of rising antimicrobial resistance.

Molecular Insights on Coffee Components as Chemical Antioxidants

Coffee is not only a delicious beverage but also an important dietary source of natural antioxidants. We live in a world where it is impossible to avoid pollution, stress, food additives, radiation, and other sources of oxidants that eventually lead to severe health disorders. Fortunately, there are chemicals in our diet that counteract the hazards posed by the reactive species that trigger oxidative stress. They are usually referred to as antioxidants; some of them can be versatile compounds that exert such a role in many ways. This review summarizes, from a chemical point of view, the antioxidant effects of relevant molecules found in coffee. Their mechanisms of action, trends in activity, and the influence of media and pH in aqueous solutions, are analyzed. Structure-activity relationships are discussed, and the protective roles of these compounds are examined. A particular section is devoted to derivatives of some coffee components, and another one to their bioactivity. The data used in the analysis come from theoretical and computational protocols, which have been proven to be very useful in this context. Hopefully, the information provided here will pro-mote further investigations into the amazing chemistry contained in our morning coffee cup.   Resumen. El café no solo es una bebida deliciosa, sino también una importante fuente dietética de antioxidantes naturales. Vivimos en un mundo donde es imposible evitar la contaminación, el estrés, los aditivos alimentarios, la radiación y otras fuentes de oxidantes que eventualmente conducen a trastornos de salud graves. Afortunadamente, existen sustancias químicas en nuestra dieta que contrarrestan los peligros planteados por las especies reactivas que desencadenan el estrés oxidativo. Por lo general, se les denomina antioxidantes; algunos de ellos pueden ser compuestos versátiles que ejercen dicho papel de muchas maneras. Este artículo de revisión resume, desde un punto de vista químico, los efectos antioxidantes de moléculas relevantes encontradas en el café. Se analizan sus mecanismos de acción, tendencias en la actividad y la influencia del medio y el pH en soluciones acuosas. Se discuten las relaciones estructura-actividad, y se examinan los roles protectores de estos compuestos. Se dedica una sección particular a los derivados de algunos componentes del café, y otra a su bioactividad. Los datos utilizados en el análisis provienen de protocolos teóricos y computacionales, que han demostrado ser muy útiles en este contexto. Se espera que la información proporcionada aquí promueva investigaciones futuras sobre la química contenida en nuestra taza de café matutina.

Nanoformulations for dismantling fungal biofilms: The latest arsenals of antifungal therapy

Globally, fungal infections have evolved as a strenuous challenge for clinicians, particularly in patients with compromised immunity in intensive care units. Fungal co-infection in Covid-19 patients has made the situation more formidable for healthcare practitioners. Surface adhered fungal population known as biofilm often develop at the diseased site to elicit antifungal tolerance and recalcitrant traits. Thus, an innovative strategy is required to impede/eradicate developed biofilm and avoid the formation of new colonies. The development of nanocomposite-based antibiofilm solutions is the most appropriate way to withstand and dismantle biofilm structures. Nanocomposites can be utilized as a drug delivery medium and for fabrication of anti-biofilm surfaces capable to resist fungal colonization. In this context, the present review comprehensively described different forms of nanocomposites and mode of their action against fungal biofilms. Amongst various nanocomposites, efficacy of metal/organic nanoparticles and nanofibers are particularly emphasized to highlight their role in the pursuit of antibiofilm strategies. Further, the inevitable concern of nanotoxicology has also been introduced and discussed with the exigent need of addressing it while developing nano-based therapies. Further, a list of FDA-approved nano-based antifungal formulations for therapeutic usage available to date has been described. Collectively, the review highlights the potential, scope, and future of nanocomposite-based antibiofilm therapeutics to address the fungal biofilm management issue.

Tyrosol-gold nanoparticle functionalized acacia gum-PVA nanofibers for mitigation of Candida biofilm

Increasing incidences of fungal infections and prevailing antifungal resistance in healthcare settings has given rise to an antifungal crisis on a global scale. The members of the genus Candida, owing to their ability to acquire sessile growth, are primarily associated with superficial to invasive fungal infections, including the implant-associated infections. The present study introduces a novel approach to combat the sessile/biofilm growth of Candida by fabricating nanofibers using a nanoencapsulation approach. This technique involves the synthesis of tyrosol (TYS) functionalized chitosan gold nanocomposite, which is then encapsulated into PVA/AG polymeric matrix using electrospinning. The FESEM, FTIR analysis of prepared TYS-AuNP@PVA/AG NF suggested the successful encapsulation of TYS into the nanofibers. Further, the sustained and long-term stability of TYS in the medium was confirmed by drug release and storage stability studies. The prepared nanomats can absorb the fluid, as evidenced by the swelling index of the nanofibers. The growth and biofilm inhibition, as well as the disintegration studies against Candida, showed 60-70 % biofilm disintegration when 10 mg of TYS-AuNP@PVA/AG NF was used, hence confirming its biological effectiveness. Subsequently, the nanofibers considerably reduced the hydrophobicity index and ergosterol content of the treated cells. Considering the challenges associated with the inhibition/disruption of fungal biofilm, the fabricated nanofibers prove their effectiveness against Candida biofilm. Therefore, nanocomposite-loaded nanofibers have emerged as potential materials that can control fungal colonization and could also promote healing.

Polysaccharide mediated nanodrug delivery: A review

Polysaccharides have drawn a lot of attention due to their potential as carriers for drugs and other bioactive chemicals. In drug delivery systems, natural macromolecules such as polysaccharides are widely utilized as polymers. This utilization extends to various polysaccharides employed in the development of nanoparticles for medicinal administration, with the goal of enhancing therapeutic efficacy while minimizing side effects. This study not only offers an overview of the existing challenges faced by these materials but also provides detailed information on key polysaccharides expertly engineered into nanoparticles. Noteworthy examples include Bael Fruit Gum, Guar Gum, Pectin, Agar, Cellulose, Alginate, Chitin, and Gum Acacia, each selected for their distinctive properties and strategically integrated into nanoparticles. The exploration of these natural macromolecules illuminates their diverse applications and underscores their potential as effective carriers in drug delivery systems. By delving into the unique attributes of each polysaccharide, this review aims to contribute valuable insights to the ongoing advancements in nanomedicine and pharmaceutical technologies. The overarching objective of this review research is to assess the utilization and comprehension of polysaccharides in nanoapplications, further striving to promote their continued integration in contemporary therapeutics and industrial practices.

Antibacterial aroma compounds as property modifiers for electrospun biopolymer nanofibers of proteins and polysaccharides: A review

Electrospinning is one of the most promising techniques for producing biopolymer nanofibers for various applications. Proteins and polysaccharides, among other biopolymers, are attractive substrates for electrospinning due to their favorable biocompatibility and biodegradability. However, there are still challenges to improve the mechanical properties, water sensitivity and biological activity of biopolymer nanofibers. Therefore, these strategies such as polymer blending, application of cross-linking agents, the addition of nanoparticles and bioactive components, and modification of biopolymer have been developed to enhance the properties of biopolymer nanofibers. Among them, antibacterial aroma compounds (AACs) from essential oils are widely used as bioactive components and property modifiers in various biopolymer nanofibers to enhance the functionality, hydrophobicity, thermal properties, and mechanical properties of nanofibers, which depends on the electrospun strategy of AACs. This review summarizes the recently reported antimicrobial activities and applications of AACs, and compares the effects of four electrospinning strategies for encapsulating AACs on the properties and applications of nanofibers. The authors focus on the correlation of the main characteristics of these biopolymer electrospun nanofibers with the encapsulation strategy of AACs in the nanofibers. Moreover, this review also particularly emphasizes the impact of the characteristics of these nanofibers on their application field of antimicrobial materials.

Biochemical and metabolomic insights into antifungal mechanism of berberine against Candida glabrata

An unprecedented expansion of antifungal therapy failure incidences in healthcare settings of Candida glabrata is the matter of global concern that needs to be addressed efficiently and effectively. In this pursuit, the present study has investigated the antifungal mechanism of benzylisoquinoline alkaloid berberine using biochemical, metabolic, and gene expression analysis, with the aim to delineate its therapeutic activity against C. glabrata and differentially fluconazole-responsive clinical isolates. Interestingly, the clinical isolates were found to be highly susceptible to berberine. Berberine was found to control the surface properties like hydrophobicity and charge of the cells. The cell membrane composition was altered by berberine, where the ergosterol and fatty acids were affected. The efflux pump activity was inhibited, and osmotic stress was generated in C. glabrata cells upon berberine exposure. The berberine has also generated oxidative stress and activated antioxidant system in C. glabrata cells. Furthermore, these observations were supported by the transcriptional expression study of C. glabrata cell genes (CDR1, RLM1, SLT2, SUR4, KRE1) and metabolomics analysis. Based on fold change analysis, the study identified 20 differential metabolites upon berberine treatment, which belong to central carbon, amino acids, and nucleotide pathways. The checkerboard analysis revealed the potentiation of some classically used antifungal drugs by berberine, thus suggesting it as a combinatorial nutraceutical adjuvant for the eradication of fungal infections. KEY POINTS: • Berberine exhibited better potency against azole-resistant clinical isolates • Berberine modulated metabolites of different pathways • Berberine generated oxidative stress and blocked efflux pump activity.

Exploration of Antibiofilm and In Vivo Wound Healing Activity of p-Cymene-Loaded Gellan/PVA Nanofibers

Wound dressings with outstanding biocompatibility, antimicrobial, and tissue regeneration activities are essential to manage emerging recalcitrant antifungal infections to speed up healing. In this study, we have engineered p-cymene-loaded gellan/PVA nanofibers using electrospinning. Morphological and physicochemical properties of the nanofibers were characterized using a multitude of techniques to validate the successful integration of p-cymene (p-cym). The fabricated nanomaterials exhibited strong antibiofilm activity against Candida albicans and Candida glabrata compared to pure p-cymene. In vitro biocompatibility assay demonstrated that nanofibers did not possess any cytotoxicity to the NIH3T3 cell lines. In vivo, full-thickness excision wound healing study showed that the nanofibers were able to heal skin lesions faster than the conventional clotrimazole gel in 24 days without forming any scar. These findings unraveled p-cymene-loaded gellan gum (GA)/poly(vinyl alcohol) (PVA) nanofibers as an effective biomaterial for cutaneous tissue regeneration.

Elucidating the lactic acid tolerance mechanism in vaginal clinical isolates of Candida glabrata

Incidence of vulvovaginal candidiasis are strikingly high and treatment options are limited with nearly 50% Candida glabrata cases left untreated or experience treatment failures. The vaginal microenvironment is rich in lactic acid, and the adaptation of C. glabrata to lactic acid (LA) is the main reason for clinical treatment failure. In the present study, C. glabrata and its vaginal clinical isolates were comprehensively investigated for their growth response, metabolic adaptation and altered cellular pathway to LA using different biochemical techniques, metabolic profiling and transcriptional studies. C. glabrata shown considerable variations in its topological and biochemical features without compromising growth in LA media. Chemical profiling data highlighted involvement of cell wall/membrane, ergosterol and oxidative stress related pathways in mediating adaptative response of C. glabrata towards LA. Further, one dimensional proton (1H) NMR spectroscopy based metabolic profiling revealed significant modulation in 19 metabolites of C. glabrata cells upon growth in LA. Interestingly myo-inositol, xylose, putrescine and betaine which are key metabolites for cell growth and viability were found to be differentially expressed by clinical isolates. These observations were supported by the transcriptional expression study of selected genes evidencing cell wall/membrane re-organisation, altered oxidative stress, and reprogramming of carbon metabolic pathways. Collectively, the study advances our understanding on adaptative response of C. glabrata in vaginal microenvironment to lactic acid for survival and virulence.

Anti-biofilm properties of eucalyptol in combination with antifungals against Candida albicans isolates in patients with hematological malignancy

Oral candidiasis is a fungal infection caused mainly by Candida albicans and it is a major problem among hematologic malignancy patients. Biofilm formation is an attributable factor to both virulence and drug resistance of Candida species. The aim of the study was to evaluate the biofilm-producing ability of oral C. albicans isolates and to evaluate the inhibitory activity of eucalyptol on Candida biofilm, alone and in combination with antifungal agents. Samples were collected from the oral cavity of 106 patients with hematologic malignancy. The isolated yeasts were identified by PCR-sequencing. Then C. albicans isolates were analyzed for their biofilm-producing ability by crystal violet staining and MTT assay. The minimum biofilm inhibition concentrations (MBIC) of eucalyptol, amphotericin B, itraconazole, and nystatin and the in vitro interaction of eucalyptol with these drugs were tested according to CLSI-M-27-A3 protocol and checkerboard methods, respectively. From 106 patients, 50 (47.2%) were confirmed for oral candidiasis [mean ± SD age 39 ± 14 years; female 31 (62%) and male 19 (38%)]. C. albicans was isolated from 40 of 50 (80%) patients. From 40 C. albicans isolates, 24 (60%) and 16 (40%) were moderate and weak biofilm producer, respectively. The geometric mean MBIC of amphotericin B, itraconazole, nystatin and eucalyptol were 3.93 µg/mL, 12.55 µg/mL, 0.75 µg/mL and 798 µg/mL, respectively. Eucalyptol interacted synergistically with amphotericin B, itraconazole and nystatin against 12.5, 10, and 22.5% of isolates, respectively. Eucalyptol demonstrated promising activity against biofilm of C. albicans when tested alone or combined with antifungal drugs.