Evaluation of minimum inhibitory concentration and minimum bactericidal concentration of royal jelly against Enterococcus faecalis, Staphylococcus aureus, and Candida albicans.

Objective: The objective of this study was to ascertain the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of royal jelly (RJ) against three microorganisms frequently linked with endodontic infections: Staphylococcus aureus, Enterococcus faecalis, and Candida albicans. Materials and Methods: Freshly harvested RJ was prepared at different concentrations (20%, 10%, 5%, 2.5%, and 1.25%) in distilled water. The microbial cultures of the target organisms were prepared. MIC was determined using a broth dilution technique, monitoring microbial growth. MBC was determined by inoculating agar plates with samples from tubes showing no apparent growth and evaluating the presence of bacterial or fungal growth following the incubation period. Results: For S. aureus, the MIC and MBC were 5 mg/ml of RJ. For E. faecalis, the MIC and MBC were 10 mg/ml of RJ. For C. albicans, both MIC and MBC were 10 mg/ml of RJ. The findings demonstrated RJ's potential to inhibit and eliminate these pathogenic microorganisms, making it a potential candidate for endodontic infection control. Conclusion: The antimicrobial properties of RJ against S. aureus, E. faecalis, and C. albicans present a promising avenue for enhancing infection control in endodontics. Additional investigations are needed to refine its use in clinical settings, especially in cases with mixed microbial infections.

Artemisinin May Disrupt Hyphae Formation by Suppressing Biofilm-Related Genes of Candida albicans: In Vitro and In Silico Approaches.

This study aimed to assess the antifungal and antibiofilm efficacy of artemisinin against Candida (C.) species, analyze its impact on gene expression levels within C. albicans biofilms, and investigate the molecular interactions through molecular docking. The antifungal efficacy of artemisinin on a variety of Candida species, including fluconazole-resistant and -susceptible species, was evaluated by the microdilution method. The effect of artemisinin on C. albicans biofilm formation was investigated by MTT and FESEM. The mRNA expression of the genes related to biofilm was analyzed by qRT-PCR. In addition, molecular docking analysis was used to understand the interaction between artemisinin and C. albicans at the molecular level with RAS1-cAMP-EFG1 and EFG1-regulated genes. Artemisinin showed higher sensitivity against non-albicans Candida strains. Furthermore, artemisinin was strongly inhibitory against C. albicans biofilms at 640 µg/mL. Artemisinin downregulated adhesion-related genes ALS3, HWP1, and ECE1, hyphal development genes UME6 and HGC1, and hyphal CAMP-dependent protein kinase regulators CYR1, RAS1, and EFG1. Furthermore, molecular docking analysis revealed that artemisinin and EFG1 had the highest affinity, followed by UME6. FESEM analysis showed that the fluconazole- and artemisinin-treated groups exhibited a reduced hyphal network, unusual surface bulges, and the formation of pores on the cell surfaces. Our study suggests that artemisinin may have antifungal potential and showed a remarkable antibiofilm activity by significantly suppressing adhesion and hyphal development through interaction with key proteins involved in biofilm formation, such as EFG1.

Combination of Systemic and Lock-Therapies with Micafungin Eradicate Catheter-Based Biofilms and Infections Caused by Candida albicans and Candida parapsilosis in Neutropenic Rabbit Models.

Vascular catheter-related infections, primarily caused by Candida albicans and Candida parapsilosis, pose significant challenges due to the formation of biofilms on catheters, leading to refractory disease and considerable morbidity. We studied the efficacy of micafungin in systemic and lock therapies to eliminate catheter-based biofilms and deep tissue infections in experimental central venous catheter (CVC)-related candidemia in neutropenic rabbits. Silastic CVCs in rabbits were inoculated with 1 × 103 CFU/mL of C. albicans or C. parapsilosis, establishing catheter-based biofilm, and subjected to various treatments. Neutropenic rabbits treated with a combination of lock therapy and systemic micafungin demonstrated the most significant reduction in fungal burden, from 5.0 × 104 to 1.8 × 102 CFU/mL of C. albicans and from 5.9 × 104 to 2.7 × 102 CFU/mL of C. parapsilosis (p ≤ 0.001), in the CVC after 24 h, with full clearance of blood cultures after 72 h from treatment initiation. The combination of lock and systemic micafungin therapy achieved eradication of C. albicans from all studied tissues (0.0 ± 0.0 log CFU/g) vs. untreated controls (liver 7.5 ± 0.22, spleen 8.3 ± 0.25, kidney 8.6 ± 0.07, cerebrum 6.3 ± 0.31, vena cava 6.6 ± 0.29, and CVC wash 2.3 ± 0.68 log CFU/g) (p ≤ 0.001). Rabbits treated with a combination of lock and systemic micafungin therapy demonstrated a ≥2 log reduction in C. parapsilosis in all treated tissues (p ≤ 0.05) except kidney. Serum (1→3)-ß-D-glucan levels demonstrated significant decreases in response to treatment. The study demonstrates that combining systemic and lock therapies with micafungin effectively eradicates catheter-based biofilms and infections caused by C. albicans or C. parapsilosis, particularly in persistently neutropenic conditions, offering promising implications for managing vascular catheter-related candidemia and providing clinical benefits in cases where catheter removal is not feasible.

Association between sleep pattern, salivary cariogenic bacteria and fungi populations, pH and buffering capacity in children: A comparative study.

BACKGROUND: Sleep quality has a significant impact on a child's health and is linked to oral and systemic diseases. It affects the circadian rhythm, which plays a crucial role in regulating the balance of the endocrine and hormonal systems. Current research has focused on exploring its role in the development of caries, which is influenced by inherent oral factors such as the composition of the oral microbiome and pH levels. OBJECTIVES: This study aimed to investigate the relationship between bacterial population, pH, and buffering properties of saliva and sleep patterns in 8- to 12-year-old children. MATERIAL AND METHODS: This cross-sectional study was conducted on 85 elementary school children aged 8-12 years. After obtaining written consent, non-stimulating saliva samples were collected using the spitting method. The participants' sleep pattern information was obtained with the use of the Persian version of the Children's Sleep Habits Questionnaire (CSHQ). Based on the results of the CSHQ, the participants were divided into 2 groups: those with appropriate sleep patterns; and those with inappropriate sleep patterns. The study compared the bacterial population of Streptococcus mutans, Lactobacillus spp. and Candida albicans, as well as the buffering capacity and pH of the saliva between the 2 groups. The statistical analysis employed the χ2 test, the independent samples t-test and Spearman's correlation. RESULTS: The group with inappropriate sleep patterns had significantly lower pH and buffering capacity (p < 0.001) and significantly higher colony counts of Lactobacillus and S. mutans (p < 0.001 and p = 0.012, respectively). There was no association between C. albicans and sleep patterns (p = 0.121). CONCLUSIONS: Inappropriate sleep patterns increase the population of caries-causing bacteria and reduce salivary pH and buffering capacity. This can be a significant factor in the development of dental caries in children aged 8-12 years.

Systemic inflammatory Th1 cytokines during Trypanosoma cruzi infection disrupt the typical anatomical cell distribution and phenotypic/functional characteristics of various cell subsets within the thymus.

The thymus plays a crucial role in T cell differentiation, a complex process influenced by various factors such as antigens, the microenvironment and thymic architecture. The way the thymus resolves infections is critical, as chronic persistence of microbes or inflammatory mediators can obstruct the differentiation. Here, we illustrate that following inflammatory T helper 1 infectious processes like those caused by Candida albicans or Trypanosoma cruzi, single positive thymocytes adopt a mature phenotype. Further investigations focused on T. cruzi infection, reveal a substantial existence of CD44+ cells in both the cortical and medullary areas of the thymus at the onset of infection. This disturbance coincides with heightened interferon gamma (IFNγ) production by thymocytes and an increased cytotoxic capacity against T. cruzi-infected macrophages. Additionally, we observe a reduced exportation capacity in T. cruzi-infected mice. Some alterations can be reversed in IFNγ knockout mice (KO). Notably, the majority of these effects can be replicated by systemic expression of interleukin (IL)-12+IL-18, underlining the predominantly inflammatory rather than pathogen-specific nature of these phenomena. Understanding the mechanisms through which systemic inflammation disrupts normal T cell development, as well as subsequent T cell exportation to secondary lymphoid organs (SLO) is pivotal for comprehending susceptibility to diseases in different pathological scenarios.

Immune response to colonization of Candida albicans in mice treated with Cefoperazone.

Candida species are a normal human flora in humans' digestive and reproductive systems, oral cavity, skin, and mucosal surfaces. This study aimed to detect the immunological role of Candida infection by using some immunological markers. The results of levels in serum showed high concentrations of IgA (56.20 ± 12 pg/ml,29.55 ± 4.5 pg/ml respectively) and IgG (12.05 ± 3.218 pg/ml, 3.836 ± 1.23 pg/ml respectively) in mice infected with C. albicans and mice treated with Cefoperazone and infected with Candida with significant differences (P value < 0.05). The results showed high serum levels of IL-17(191.5 ± 42.81 pg/ml) and TLR2(7.651 ± 1.5 pg/ml) in group mice infected with C. albicans compared with negative control and group mice treated with Cefoperazone. Also, high levels of IL-17 (91.33 ± 4.816 pg/ml) and TLR2 (2.630 ± 0.5 pg/ml) in group mice treated with Cefoperazone and infected with Candida compared with negative control and group mice treated with Cefoperazone (P value < 0.05). The results of antibodies and immunological markers in the intestine showed high levels of IgA and IgG in mice infected with C.albicans (55.7 ± 4.9 pg/ml, 18.19 ± 0.63 pg/ml respectively).Also,IgA and IgG in mice treated with Cefoperazone and infected with Candida were high level (43.04 ± 2.1 pg/ml, 2.927 ± 0.2 pg/ml respectively) in mice infected with C. albicans with significant differences (P value < 0.05). The results levels of IL-17 and TLR2 were increased in mice infected with C. albicans (191.5 ± 42.81 pg/ml, 7.651 ± 1.5 pg/ml respectively) and mice treated with Cefoperazone and infected with Candida (91.33 ± 4.816 pg/ml,2.630 ± 0.5 pg/ml respectively) with significant differences (P < 0.05). In conclusion, this study demonstrated that cefoperazone treatment and infection by Candida albicans changed the microbiome components in the gut and finally can change host immune responses. It was observed that elevated levels of the antibodies production (IgA and IgG) and immunological markers (IL-17, and TLR2) in serum and the gut.

Effect of ozone gas on cultures of Candida albicans and Aspergillus fumigatus: evaluation of two ozonation devices.

INTRODUCTION: Candida albicans and Aspergillus fumigatus are two important agents of Healthcare-associated infections. This study aimed to evaluate the antifungal activity of ozone (O3) gas produced by two commercial devices against cultures of these two species. METHODOLOGY: Sterile plastic plates were inoculated with C. albicans and A. fumigatus and placed on a countertop at three distances (30 cm, 1 m, and 2 m) and three positions in relation to the wall (near, middle, and away), considering the source of O3. Plates were exposed to O3 for one hour and incubated. After incubation, the counting of colony-forming units was performed. As a control, an inoculated plate was incubated, without being exposed to O3. Tests were carried out with two different devices (namely, Mod.I and Mod.II), with the air conditioner on and off, in triplicate. RESULTS: Both devices showed antifungal activity. Mod. I presented better results, due to a higher flow rate. The best activity was on plates at 30 cm, middle position. Contrarily, on plates at 2m, near the wall, the inhibition activity was lower. The best results were obtained with the air conditioner off. Candida albicans was more sensitive to O3 than A. fumigatus. CONCLUSIONS: This method of decontamination by O3 gas shows potential due to its fast and easy execution. The establishment of new protocols for hygiene and hospital disinfection using this approach should be considered, which may reduce environmental contamination by fungi and, consequently, the burden of fungal infections.

Candida albicans overgrowth disrupts the gut microbiota in mice bearing oral cancer.

Candida albicans is one of the most common opportunistic fungi in cancer patients. This study explored the influence of C. albicans on gut microbiota in oral tumour-bearing mice by means of 16S rRNA sequencing and ITS sequencing. It was found that C. albicans infection induced the decrease of alpha diversity of bacteria and fungi in the gut microbiome. For the bacteria, C. albicans caused the reduction of Ralstonia, Alistipes, Clostridia UCG-014, Ruminococcus, and Lachnospiraceae NK4A136 group. For the fungi, C. albicans inhibited the growth of other fungi including Aspergillus, Cladosporium, and Bipolaris. The neutralisation of γδT cells partly alleviated the out-of-balance of Firmicutes/Bacteroidota (F/B) ratio in the gut caused by C. albicans infection. However, γδT cell neutralisation boosted the overgrowth of C. albicans. Additionally, IL-17A neutralisation aggravated the microbial dysbiosis of bacteria and fungi caused by C. albicans infection. Further analysis indicated that C. albicans overgrowth might influence the correlations between fungal and bacterial kingdoms. In conclusion, C. albicans infection disturbed the gut microbiota of both bacteria and fungi in oral tumour-bearing mice, which may be associated with the intestinal immune components including γδT cells and IL-17A.

Microbiological Evaluation of Herbal Extracts against Candida albicans in Early Childhood Caries Patients: An In Vitro Study.

Purpose: The current literature proposes a probable role of Candida albicans (C. albicans) in its etiopathogenesis in early childhood caries (ECC). This study aimed to isolate C. albicans species in children with and without ECC and compare the antifungal efficacy of neem, miswak, cinnamon, clove, stevia, and ketoconazole. This study also aimed to assess and compare salivary pH in children with and without ECC. Materials and methods: A total of 60 children were included in the study, who were divided into two groups-group I (children with ECC) and group II (children without ECC). Plaque samples were collected and streaked on Sabouraud dextrose agar (SDA). C. albicans isolates were evaluated, and their susceptibility to herbal agents was tested and compared. Saliva samples were collected, and salivary pH was tested and compared. Results: The presence of C. albicans was significantly higher in group I (76.7%) as compared to group II (23.3%). The mean zone of inhibition for neem was 4.9 mm, whereas, for miswak, it was 4.5 mm; for cinnamon, 9.3 mm; for clove, 3.8 mm; for stevia, 10.9 mm; and for ketoconazole it was 21.09 mm. The mean salivary pH for group I was 6.7, and that for group II was 7.3. Conclusion: Candida albicans (C. albicans) carriage in children with ECC was significantly higher than in children without ECC. All herbal agents showed significant antifungal activity, with stevia showing the highest activity. The average salivary pH of children without ECC was slightly higher than that of children with ECC. How to cite this article: Siddaiah SB, Sinha S, BR A. Microbiological Evaluation of Herbal Extracts against Candida albicans in Early Childhood Caries Patients: An In Vitro Study. Int J Clin Pediatr Dent 2024;17(1):26-30.

Evaluation of antifungal activity of visible light-activated doped TiO2 nanoparticles.

Titanium dioxide (TiO2) is a well-known material for its biomedical applications, among which its implementation as a photosensitizer in photodynamic therapy has attracted considerable interest due to its photocatalytic properties, biocompatibility, high chemical stability, and low toxicity. However, the photoactivation of TiO2 requires ultraviolet light, which may lead to cell mutation and consequently cancer. To address these challenges, recent research has focused on the incorporation of metal dopants into the TiO2 lattice to shift the band gap to lower energies by introducing allowed energy states within the band gap, thus ensuring the harnessing of visible light. This study presents the synthesis, characterization, and application of TiO2 nanoparticles (NPs) in their undoped, doped, and co-doped forms for antimicrobial photodynamic therapy (APDT) against Candida albicans. Blue light with a wavelength of 450 nm was used, with doses ranging from 20 to 60 J/cm2 and an NP concentration of 500 µg/ml. It was observed that doping TiO2 with Cu, Fe, Ag ions, and co-doping Cu:Fe into the TiO2 nanostructure enhanced the visible light photoactivity of TiO2 NPs. Experimental studies were done to investigate the effects of different ions doped into the TiO2 crystal lattice on their structural, optical, morphological, and chemical composition for APDT applications. In particular, Ag-doped TiO2 emerged as the best candidate, achieving 90-100% eradication of C. albicans.

Insights into betulinic acid as a promising molecule to fight the interkingdom biofilm Staphylococcus aureus-Candida albicans.

The demand for antibiofilm molecules has increased for several years due to their potential to fight biofilm-associated infections such as those including the interkingdom Staphylococcus aureus - Candida albicans occurring in clinical settings worldwide. Recently, we have identified a pentacyclic triterpenoid compound identified as betulinic acid (BA) from invasive macrophytes with interesting antibiofilm properties. Our study aimed at providing insights into the mechanism of action of BA against the clinically relevant bi-species S. aureus-C. albicans biofilms. Microscopy examinations, flow cytometry and crystal violet assays confirmed that BA was effective for damaging mature S. aureus-C. albicans biofilms or inhibiting their formation, reducing biofilm biomass by 70% on average and without microbicidal activity. Results suggested an action of BA on cell membranes, inducing changes in properties such as composition, hydrophobicity and fluidity as observed in C. albicans, which may hinder the early adhesion step, the biofilm growth and the physical interactions of both microbial species. Further results of real-time PCR argued in favor of a reduction of S. aureus-C. albicans physical interaction due to BA by the modulation of biofilm-related gene expression as observed in early stages of biofilm formation. This study revealed the potential of BA as candidate agent for the prevention and treatment of S. aureus-C. albicans biofilm-related infections.

Synergistic activity of crocin and crocin loaded in niosomes alone and in combination with fluconazole against Candida albicans isolates: In vitro and in silico study.

INTRODUCTION: Since the drug resistance in Candida species is becoming a serious clinical challenge, novel alternative therapeutic options, particularly herbal medicine, have attracted increasing interest. This study aimed to pinpoint the potential antifungal activity of crocin (Cro), the efficacy of the niosomal formulation of Cro (NCro), and the synergistic activity of both formulations in combination with fluconazole (FLC) against susceptible and resistant C. albicans isolates. MATERIAL AND METHODS: NCro was formulated using the heating method. The in vitro antimycotic activity of Cro, NCro, and FLC was evaluated. Checkerboard and isobologram assays evaluated the interaction between both formulations of Cro and FLC. Necrotic and apoptotic effects of different agents were analyzed using the flow cytometry method. In silico study was performed to examine the interactions between Lanosterol 14 alpha-demethylase and Cro as a part of our screening compounds with antifungal properties. RESULTS: NCro exhibited high entrapment efficiency up to 99.73 ± 0.54, and the mean size at 5.224 ± 0.618 µm (mean ± SD, n = 3). Both formulations of Cro were shown to display good anticandidal activity against isolates. The synergistic effect of the NCro in combination with FLC is comparable to Cro (P-value =0.03). Apoptotic indicators confirmed that tested compounds caused cell death in isolates. The docking study indicated that Cro has interactivity with the protein residue of 14α-demethylase. CONCLUSION: The results showed a remarkable antifungal effect by NCro combined with FLC. Natural compounds, particularly nano-sized carrier systems, can act as an effective therapeutic option for further optimizing fungal infection treatment.

Candida albicans cDNA library screening reveals novel potential diagnostic targets for invasive candidiasis.

The detection of patterns associated with the invasive form of Candida albicans, such as Candida albicans germ tube antibodies (CAGTA), is a useful complement to blood culture for Invasive Candidiasis (IC) diagnosis. As CAGTA are detected by a non-standardisable and non-automatable technique, a Candida albicans cDNA expression library was screened with CAGTA isolated from serum of an animal model of invasive candidiasis, and five protein targets were identified: hyphally regulated cell wall protein 1 (Hyr1), enolase 1 (Eno1), coatomer subunit gamma (Sec21), a metallo-aminopeptidase (Ape2) and cystathionine gamma-lyase (Cys3). Homology with proteins from other organisms rules out Cys3 as a good biomarker while Sec21 results suggest that it is not in the germ tubes surface but secreted to the external environment. Our analysis propose Ape2, Sec21 and a region of Hyr1 different from the one currently being studied for immunoprotection as potential biomarker candidates for the diagnosis of IC.

Controlling Candida: immune regulation of commensal fungi in the gut.

The intestinal microbiome harbors fungi that pose a significant risk to human health as opportunistic pathogens and drivers of inflammation. Inflammatory and autoimmune diseases are associated with dysbiotic fungal communities and the expansion of potentially pathogenic fungi. The gut is also the main reservoir for disseminated fungal infections. Immune interactions are critical for preventing commensal fungi from becoming pathogenic. Significant strides have been made in defining innate and adaptive immune pathways that regulate intestinal fungi, and these discoveries have coincided with advancements in our understanding of the fungal molecular pathways and effectors involved in both commensal colonization and pathogenesis within the gut. In this review, we will discuss immune interactions important for regulating commensal fungi, with a focus on how specific cell types and effectors interact with fungi to limit their colonization or pathogenic potential. This will include how innate and adaptive immune pathways target fungi and orchestrate antifungal immune responses, in addition to how secreted immune effectors, such as mucus and antimicrobial peptides, regulate fungal colonization and inhibit pathogenic potential. These immune interactions will be framed around our current understanding of the fungal effectors and pathways regulating colonization and pathogenesis within this niche. Finally, we highlight important unexplored mechanisms by which the immune system regulates commensal fungi in the gut.

From plants to particles: herbal solutions and nanotechnology combating resistant vulvovaginal candidiasis.

Despite having current advanced therapy, vulvovaginal candidiasis (VVC) remains a common yet debated healthcare-associated topic worldwide due to multi-drug resistance Candida species. In our review, we outlined and highlighted upcoming values with scope of existing and emerging information regarding the possibility of using various natural molecules combined with modern technology that shows promising anti-candida activity in VVC. Furthermore, in this review, we compiled herbal drug molecules and their nanocarriers approach for enhancing the efficacy and stability of herbal molecules. We have also summarized the patent literature available on herbal drug molecules and their nanoformulation techniques that could alternatively become a new innovative era to combat resistance VVC.

There is a type of fungi called Candida that is responsible for infections like vulvovaginal candidiasis in the human vagina. Due to resistance of currently available antifungal medicines, there are side effects on the body. Therefore, researchers are studying and preparing natural-based medicine from plants which may provide very good effects on human health. Also, herbal-based medicines have shown evidence based good antifungal activity. Combinations of herbal drugs with very small-sized particles called nanomaterials have added advantage as it helps herbs (drug) to reach their target. Its activity is enhanced as it stays for longer time in the body. So, in the future more research is needed to make sure plant medicines are safe and work well on vaginal infections and its uses should be promoted so that could be a good solution for treating vaginal candidiasis.

Anti-Candida activity and biocompatibility of silver nanoparticles associated with denture glaze: a new approach to the management of denture stomatitis.

The association of silver nanoparticles (AgNps) to sealant agent Palaseal® can be a promising alternative for complete denture wearers who may develop denture stomatitis (DS). The study aimed to evaluate the anti-Candida and biocompatible potential of silver nanoparticles synthesized by three routes associated with denture glaze to prevent and/or treat oral candidiasis. Surface acrylic resin specimens were treated with different associations of glaze with AgNps (VER+AgUV, VER+AgTurk and VER+AgGm). As controls, specimens were treated with glaze+nystatin (VER+Nyst), glaze only (VER) or submerged in PBS (PBS). Afterwards, Candida albicans biofilm was developed for 24 h, 15 d and 30 d. Subsequently, the biofilm was quantified by CFU/mL, XTT assay and confocal laser scanning microscopy. Fibroblasts were submitted to conditioned medium with the same associations for 24, 48 and 72 h and LIVE/DEAD® viability test was carried out. Regardless of the period, there was a significant reduction (p < 0.01) of viable fungal cells load, as well as inhibition of fungal metabolic activity, in specimens treated with glaze+AgNps associations, compared to VER and PBS. The anti-Candida effects of the associations were similar to the VER+Nyst group, with emphasis on VER+AgGm, which showed the highest percentage values of non-viable fungal cells maintained over time. The associations did not prove toxicity to fibroblasts. The AgNps exerted antimicrobial activity against C. albicans biofilms and are biocompatible. The most effective results were achieved with the association of glaze+silver nanoparticles synthesized by the green chemistry method (AgGm), proving to be an innovative alternative in the management of DS.

Antifungal drug discovery for targeting Candida albicans morphogenesis through structural dynamics study.

In response to the escalating threat of drug-resistant fungi to human health, there is an urgent need for innovative strategies. Our focus is on addressing this challenge by exploring a previously untapped target, yeast casein kinase (Yck2), as a potential space for antifungal development. To identify promising antifungal candidates, we conducted a thorough screening of the diverse-lib drug-like molecule library, comprising 99,288 molecules. Five notable drug-like compounds with diverse-lib IDs 24334243, 24342416, 17516746, 17407455, and 24360740 were selected based on their binding energy scores surpassing 11 Kcal/mol. Our investigation delved into the interaction studies and dynamic stability of these compounds. Remarkably, all selected molecules demonstrated acceptable RMSD values during the 200 ns simulation, indicating their stable nature. Further analysis through Principal Component Analysis (PCA)-based Free Energy Landscape (FEL) revealed minimal energy transitions for most compounds, signifying dynamic stability. Notably, the two compounds exhibited slightly different behaviour in terms of energy transitions. These findings mark a significant breakthrough in the realm of antifungal drugs against C. albicans by targeting the Yck2 protein. However, it is crucial to note that additional experimental validation is imperative to assess the efficacy of these molecules as potential antifungal candidates. This study serves as a promising starting point for further exploration and development in the quest for effective antifungal solutions.Communicated by Ramaswamy H. Sarma.

Water Extracts from Industrial Hemp Waste Inhibit the Adhesion and Development of Candida Biofilm and Showed Antioxidant Activity on HT-29 Colon Cancer Cells.

The evolution of regulatory perspectives regarding the health and nutritional properties of industrial hemp-based products (Cannabis sativa L.) has pushed research to focus on the development of new methods for both the extraction and formulation of the bioactive compounds present in hemp extracts. While the psychoactive and medicinal properties of hemp-derived cannabinoid extracts are well known, much less has been investigated on the functional and antimicrobial properties of hemp extracts. Within the hemp value chain, various agricultural wastes and by-products are generated. These materials can be valorised through eco-innovations, ultimately promoting sustainable economic development. In this study, we explored the use of waste from industrial light cannabis production for the extraction of bioactive compounds without the addition of chemicals. The five extracts obtained were tested for their antimicrobial activity on both planktonic and sessile cells of pathogenic strains of the Candida albicans, Candida parapsilosis, and Candida tropicalis species and for their antioxidant activity on HT-29 colon cancer cells under oxidative stress. Our results demonstrated that these extracts display interesting properties both as antioxidants and in hindering the development of fungal biofilm, paving the way for further investigations into the sustainable valorisation of hemp waste for different biomedical applications.

Pore-forming peptide C14R exhibits potent antifungal activity against clinical isolates of Candida albicans and Candida auris.

Introduction: Invasive candidiasis is a global public health problem as it poses a significant threat in hospital-settings. The aim of this study was to evaluate C14R, an analog derived from peptide BP100, as a potential antimicrobial peptide against the prevalent opportunistic yeast Candida albicans and the emergent multidrug-resistant yeast Candida auris. Methods: Antifungal susceptibility testing of C14R against 99 C. albicans and 105 C. auris clinical isolates from Colombia, was determined by broth microdilution. Fluconazole was used as a control antifungal. The synergy between C14R and fluconazole was assessed in resistant isolates. Assays against fungal biofilm and growth curves were also carried out. Morphological alterations of yeast cell surface were evaluated by scanning electron microscopy. A permeability assay verified the pore-forming ability of C14R. Results: C. albicans and C. auris isolates had a geometric mean MIC against C14R of 4.42 µg/ml and 5.34 µg/ml, respectively. Notably, none of the isolates of any species exhibited growth at the highest evaluated peptide concentration (200 µg/ml). Synergistic effects were observed when combining the peptide and fluconazole. C14R affects biofilm and growth of C. albicans and C. auris. Cell membrane disruptions were observed in both species after treatment with the peptide. It was confirmed that C14R form pores in C. albicans' membrane. Discussion: C14R has a potent antifungal activity against a large set of clinical isolates of both C. albicans and C. auris, showing its capacity to disrupt Candida membranes. This antifungal activity remains consistent across isolates regardless of their clinical source. Furthermore, the absence of correlation between MICs to C14R and resistance to fluconazole indicates the peptide's potential effectiveness against fluconazole-resistant strains. Our results suggest the potential of C14R, a pore-forming peptide, as a treatment option for fungal infections, such as invasive candidiasis, including fluconazole and amphotericin B -resistant strains.

Fabrication and evaluation of ribavirin-loaded electrospun nanofibers as an antimicrobial wound dressing.

Background: Skin is regarded as an essential first line of defense against harmful pathogens and it hosts an ecosystem of microorganisms that create a widely diverse skin microbiome. In chronic wounds, alterations in the host-microbe interactions occur forming polymicrobial biofilms that hinder the process of wound healing. Ribavirin, an antiviral drug, possesses antimicrobial activity, especially against Pseudomonas aeruginosa and Candida albicans, which are known as the main opportunistic pathogens in chronic wounds. Rationale: In this study, electrospun nanofiber systems loaded with ribavirin were developed as a potential wound dressing for topical application in chronic wounds. Ribavirin was chosen in this study owing to the emerging cases of antimicrobial (antibiotics and antifungal) resistance and the low attempts to discover new antimicrobial agents, which encouraged the repurposing use of current medication as an alternative solution in case of resistance to the available agents. Additionally, the unique mechanism of action of ribavirin, i.e., perturbing the bacterial virulence system without killing or stopping their growth and rendering the pathogens disarmed, might be a promising choice to prevent drug resistance. Cyclodextrin (CD) was utilized to formulate ribavirin as an electrospun nanofibers delivery system to enhance the absorption and accelerate the release of ribavirin for topical use. Results: The results demonstrated a successful ribavirin nanofibers fabrication that lacked beads and pores on the nanofibrous surfaces. Ribavirin underwent a physical transformation from crystalline to amorphous form, as confirmed by X-ray diffraction analysis. This change occurred due to the molecular dispersion after the electrospinning process. Additionally, the CD enhanced the encapsulation efficiency of ribavirin in the nanofibers as observed from the drug-loading results. Polyvinylpyrrolidone (PVP) and CD increased ribavirin released into the solution and the disintegration of fibrous mats which shrank and eventually dissolved into a gel-like substance as the ribavirin-loaded fibers began to break down from their border toward the midpoint. Cytotoxicity of ribavirin and CD was evaluated against human dermal fibroblasts (HFF-1) and the results showed a relatively safe profile of ribavirin upon 24-hour cell exposure, while CD was safe within 24- and 48-hour. Conclusion: This study provides valuable insights into the potential application of our nanofibrous system for treating chronic wounds; however, further antimicrobial and in-vivo studies are required to confirm its safety and effectiveness.