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.

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.

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.

Insights into the anti-Candida albicans properties of natural phytochemicals: An in vitro and in vivo investigation.

Invasive candidiasis, attributed to Candida albicans, has long been a formidable threat to human health. Despite the advent of effective therapeutics in recent decades, the mortality rate in affected patient populations remains discouraging. This is exacerbated by the emergence of multidrug resistance, significantly limiting the utility of conventional antifungals. Consequently, researchers are compelled to continuously explore novel solutions. Natural phytochemicals present a potential adjunct to the existing arsenal of agents. Previous studies have substantiated the efficacy of phytochemicals against C. albicans. Emerging evidence also underscores the promising application of phytochemicals in the realm of antifungal treatment. This review systematically delineates the inhibitory activity of phytochemicals, both in monotherapy and combination therapy, against C. albicans in both in vivo and in vitro settings. Moreover, it elucidates the mechanisms underpinning the antifungal properties, encompassing (i) cell wall and plasma membrane damage, (ii) inhibition of efflux pumps, (iii) induction of mitochondrial dysfunction, and (iv) inhibition of virulence factors. Subsequently, the review introduces the substantial potential of nanotechnology and photodynamic technology in enhancing the bioavailability of phytochemicals. Lastly, it discusses current limitations and outlines future research priorities, emphasizing the need for high-quality research to comprehensively establish the clinical efficacy and safety of phytochemicals in treating fungal infections. This review aims to inspire further contemplation and recommendations for the effective integration of natural phytochemicals in the development of new medicines for patients afflicted with C. albicans.

Effect of Pulsatilla decoction on vulvovaginal candidiasis in mice. Evidences for its mechanisms of action.

BACKGROUND: Vulvovaginal candidiasis (VVC) is a common infection that affects the female reproductive tract. Pulsatilla decoction (PD), a traditional Chinese herbal medicine, is a classic and effective prescription for VVC. However, its mechanism of action remains unclear. PURPOSE: This study aimed to evaluate the efficacy and potential mechanism of action of the n-butanol extract of Pulsatilla decoction (BEPD) in VVC treatment. METHODS: High performance liquid chromatography (HPLC) was used to detect the main active ingredients in BEPD. A VVC-mouse model was constructed using an estrogen-dependent method to evaluate the efficacy of BEPD in VVC treatment. Fungal burden and morphology in the vaginal cavity were comprehensively assessed. Candida albicans-induced inflammation was examined in vivo and in vitro. The effects of BEPD on the Protein kinase Cδ (PKCδ) /NLR family CARD domain-containing protein 4 (NLRC4)/Interleukin-1 receptor antagonist (IL-1Ra) axis were analyzed using by immunohistochemistry (IHC), immunofluorescence (IF), western blot (WB), and reverse transcription-quantitative polymerase chain reaction (qRT-PCR). RESULTS: BEPD inhibited fungal growth in the vagina of VVC mice, preserved the integrity of the vaginal mucosa, and suppressed inflammatory responses. Most importantly, BEPD activated the "silent" PKCδ/NLRC4/IL-1Ra axis and negatively regulated NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome, thereby exerting a therapeutic efficacy on VVC. CONCLUSIONS: BEPD effects on mice with VVC were dose-dependent. BEPD protects against VVC by inhibiting inflammatory response and NLRP3 inflammasome via the activation of the PKCδ/NLRC4/IL-1Ra axis. This study revealed the pharmacological mechanism of BEPD in VVC treatment and provided further evidence for the application of BEPD in VVC treatment.

Essential oil and plant extract of oregano as agents influencing the virulence factors of Candida albicans.

Candida albicans, a polymorphic yeast, is a physiological component of the human and animal commensal microbiome. It is an etiological factor of candidiasis, which is treated by azole antifungals. Growing resistance to azoles is a reason to look for other alternative treatment options. The pharmacotherapeutic use of plant extracts and essential oils has become increasingly important. In our experiment, C. albicans showed susceptibility to four observed plant extracts and essential oils from peppermint ( Mentha piperita), thyme ( Thymus vulgaris), sage ( Salvia officinalis), and oregano ( Origanum vulgare). Oregano plant extract and essential oil showed the highest antifungal activity, at MIC values of 4.9 mg/mL and 0.4 mg/mL respectively. Therefore, it was subjected to further research on the influence of virulence factors - biofilm formation, extracellular phospholipase production and germ tube formation. Oregano plant extract and essential oil showed an inhibitory effect on the observed C. albicans virulence factors at relatively low concentrations. The extract inhibited the adherence of cells at MIC 12.5 mg/mL and essential oil at MIC 0.25 mg/mL. Degradation of the formed biofilm was detected at MIC 14.1 mg/mL for plant extract and at MIC 0.4 mg/mL for essential oil. Extracellular phospholipase production was most effectively inhibited by the essential oil. In particular, the number of isolates with intensive extracellular phospholipase production decreased significantly. Of the 12 isolates intensively producing extracellular phospholipase, only 1 isolate (4.5%) retained intense production. Essential oil caused up to a 100 % reduction in germ tubes formation and plant extract reduced their formation depending on the concentration as follows: 2.6% (0.8 mg/mL), 21.2 % (6.25 mg/mL), and 64.5 % (12.5 mg/mL) compared to the control.

Copper Sulfate Combined with Photodynamic Therapy Enhances Antifungal Effect by Downregulating AIF1.

Candida albicans is a clinically significant opportunistic fungus that is generally treated with antifungal drugs such as itraconazole and fluconazole. However, the recent emergence of fungal resistance has made treatment increasingly difficult. Therefore, novel antifungal treatment methods are urgently required. Hexanol ethosome photodynamic therapy (HE-PDT) is a method that uses photosensitizers (PS), such as hexanol ethosome, to exert antifungal effects, and can be used to treat resistant fungal strains. However, due to the high dose of PS required for antifungal treatment, excess photosensitizers may remain. Furthermore, once exposed to light, normal tissues or cells are damaged after photodynamic therapy, which limits the clinical application of HE-PDT. Therefore, improving the efficacy without increasing the dose is the key to this treatment. In this study, the antifungal effect of copper sulfate combined with HE-PDT was investigated, and its mechanism was explored. The results suggested that exogenous copper sulfate significantly increased the antifungal effect of HE-PDT by enhancing the rate of C. albicans inhibition, increasing reactive oxygen species (ROS) accumulation, increasing the rate of apoptosis, and altering the mitochondrial membrane potential (MMP) and ATP concentration, which is related to the downregulation of apoptosis-inducing factor (AIF1) expression. In conclusion, copper sulfate combined with photodynamic therapy significantly inhibited the activity of C. albicans by inducing apoptosis. The combined approach reported herein provides new insights for future antifungal therapy.

Physical impediment to sodium houttuyfonate conversely reinforces ß-glucan exposure stimulated innate immune response to Candida albicans.

Candida albicans is a dimorphic opportunistic pathogen in immunocompromised individuals. We have previously demonstrated that sodium houttuyfonate (SH), a derivative of medicinal herb Houttuynia cordata Thunb, was effective for antifungal purposes. However, the physical impediment of SH by C. albicans ß-glucan may weaken the antifungal activity of SH. In this study, the interactions of SH with cell wall (CW), extracellular matrix (EM), CW ß-glucan, and a commercial ß-glucan zymosan A (ZY) were inspected by XTT assay and total plate count in a standard reference C. albicans SC5314 as well as two clinical fluconazole-resistant strains Z4935 and Z5172. After treatment with SH, the content and exposure of CW ß-glucan, chitin, and mannan were detected, the fungal clearance by phagocytosis of RAW264.7 and THP-1 was examined, and the gene expressions and levels of cytokines TNF-ɑ and IL-10 were also monitored. The results showed that SH could be physically impeded by ß-glucan in CW, EM, and ZY. This impediment subsequently triggered the exposure of CW ß-glucan and chitin with mannan masked in a time-dependent manner. SH-induced ß-glucan exposure could significantly enhance the phagocytosis and inhibit the growth of C. albicans. Meanwhile, the SH-pretreated fungal cells could greatly stimulate the cytokine gene expressions and levels of TNF-ɑ and IL-10 in the macrophages. In sum, the strategy that the instant physical impediment of C. albicans CW to SH, which can induce the exposure of CW ß-glucan may be universal for C. albicans in response to physical deterrent by antifungal drugs.

'Green' silver nanoparticles combined with tyrosol as potential oral antimicrobial therapy.

OBJECTIVES: This study aimed to evaluate silver nanoparticles (AgNPs) obtained by a 'green' route associated or not to tyrosol (TYR) against Streptococcus mutans and Candida albicans in planktonic and biofilms states. METHODS: AgNPs were obtained by a 'green' route using pomegranate extract. The minimum inhibitory concentration (MIC) against S. mutans and C. albicans was determined for AgNPs and TYR combined and alone, and fractional inhibitory concentration index (FICI) was calculated. Single biofilms of C. albicans and S. mutans were cultivated for 24 h and then treated with drugs alone or in combination for 24 h. RESULTS: AgNPs and TYR were effective against C. albicans and S. mutans considering planktonic cells alone and combined. The MIC values obtained for C. albicans was 312.5 µg/mL (AgNPs) and 50 mM (TYR) and for S. mutans was 78.1 µg/mL (AgNPs) and 90 mM (TYR). The combination of these antimicrobial agents was also effective against both microorganisms: 2.44 µg/mL/0.08 mM (AgNPs/TYR) for C. albicans and 39.05 µg/mL /1.25 mM (AgNPs/TYR) for S. mutans. However, synergism was observed only for C. albicans (FICI 0.008). When biofilm was evaluated, a reduction of 4.62 log10 was observed for S. mutans biofilm cells treated with AgNPs (p < 0.05, Tukey test). However, the addition of TYR to AgNPs did not improve their action against biofilm cells (p > 0.05). AgNPs combined with TYR demonstrated a synergistic effect against C. albicans biofilms. CONCLUSIONS: These findings suggest the potential use of AgNPs with or without TYR against C. albicans and S. mutans, important oral pathogens. CLINICAL SIGNIFICANCE: AgNPs obtained by a 'green' route combined or not with TYR can be an alternative to develop several types of oral antimicrobial therapies and biomaterials.

Cryptocarya moschata extract decreases single and mixed biofilms on acrylic resins.

OBJECTIVE: This study proposed to assess the effect of Cryptocarya moschata extract on single and mixed biofilms formed on denture base and reline acrylic resin. MATERIALS AND METHODS: Single and mixed biofilms of Candida albicans and Streptococcus mutans were formed on the samples and treated with C. moschata extract; Nystatin solution at 100,000 IU/mL or Penicillin antibiotic solution at 100,000 IU/mL; or PBS solution. Antimicrobial activity was analyzed by counting colony-forming units, metabolism assay, assessment of protein components of the biofilm matrix, and of cell viability using confocal laser scanning microscopy (CLSM). Data were submitted to ANOVA and Tukey's post-test (α = 0.05). RESULTS: Cryptocarya moschata extract reduced cell viability of C. albicans and S. mutans single and mixed biofilms formed on samples. For all types of biofilms in the C. moschata group, there was a log reduction of the biofilm, proven by the Alamar Blue assay. Analyzing the extracellular matrix protein components, groups treated with the extract exhibited a lower level of fluorescence compared to the PBS groups. Reduction in thickness biofilm and viable cells was perceptible in the C. moschata group when assessing through CLSM. CONCLUSION: Cryptocarya moschata extract reduced the single and mixed biofilms of C. albicans and S. mutans on acrylic resins.

Antibiofilm activity of lawsone against polymicrobial enterohemorrhagic Escherichia coli O157:H7 and Candida albicans by suppression of curli production and hyphal growth.

BACKGROUND: Most bacteria and fungi form biofilms that attach to living or abiotic surfaces. These biofilms diminish the efficacy of antimicrobial agents and contribute to chronic infections. Furthermore, multispecies biofilms composed of bacteria and fungi are often found at chronic infection sites. PURPOSE: In this study, lawsone (2­hydroxy-1,4-naphthoquinone) and its parent 1,4-naphthoquinone were studied for antimicrobial and antibiofilm activities against single-species and multispecies biofilms of enterohemorrhagic Escherichia coli O157:H7 (EHEC) and Candida albicans. METHODS: Biofilm formation assays, biofilm eradication assays, antimicrobial assays, live cell imaging microscopy, confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM), extracellular polymeric substances and indole production, cell surface hydrophilicity assay, cell motility, cell aggregation, hyphal growth, dual species biofilm formation, quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), and toxicity assays on plant seed germination and nematode model were utilized to investigate how lawsone affect biofilm development. RESULTS: Sub-inhibitory concentrations of lawsone (35 µg/ml) significantly inhibited single-and multispecies biofilm development. Lawsone reduced the production of curli and indole, and the swarming motility of EHEC, efficiently inhibited C. albicans cell aggregation and hyphal formation, and increased the cell surface hydrophilicity of C. albicans. Transcriptomic analysis showed that lawsone suppressed the expression of the curli-related genes csgA and csgB in EHEC, and the expression of several hypha- and biofilm-related genes (ALS3, ECE1, HWP1, and UME6) in C. albicans. In addition, lawsone up to 100 µg/ml was nontoxic to the nematode Caenorhabditis elegans and to the seed growth of Brassica rapa and Triticum aestivum. CONCLUSION: These results show that lawsone inhibits dual biofilm development and suggest that it might be useful for controlling bacterial or fungal infections and multispecies biofilms.

Questioning the 14-day dogma in candidemia treatment duration.

The growing threat of antimicrobial resistance (AMR) is a global concern. With AMR directly causing 1.27 million deaths in 2019 and projections of up to 10 million annual deaths by 2050, optimising infectious disease treatments is imperative. Prudent antimicrobial use, including treatment duration, can mitigate AMR emergence. This is particularly critical in candidemia, a severe condition with a 45% crude mortality rate, as the 14-day minimum treatment period has not been challenged in randomised comparison. A comprehensive literature search was conducted in August 2023, revealing seven original articles and two case series discussing treatment durations of less than 14 days for candidemia. No interventional trials or prospective observational studies assessing shorter durations were found. Historical studies showed varying candidemia treatment durations, questioning the current 14-day minimum recommendation. Recent research observed no significant survival differences between patients receiving shorter or longer treatment, emphasising the need for evidence-based guidance. Treatment duration reduction post-blood culture clearance could decrease exposure to antifungal drugs, limiting selection pressure, especially in the context of emerging multiresistant Candida species. Candidemia's complexity, emerging resistance and potential for shorter in-hospital stays underscore the urgency of refining treatment strategies. Evidence-driven candidemia treatment durations are imperative to balance efficacy with resistance prevention and ensure the longevity of antifungal therapies. Further research and clinical trials are needed to establish evidence-based guidelines for candidemia treatment duration.

Amphotericin B-loaded natural latex dressing for treating Candida albicans wound infections using Galleria mellonella model.

Amphotericin B (AmB) is the gold standard for antifungal drugs. However, AmB systemic administration is restricted because of its side effects. Here, we report AmB loaded in natural rubber latex (NRL), a sustained delivery system with low toxicity, which stimulates angiogenesis, cell adhesion and accelerates wound healing. Physicochemical characterizations showed that AmB did not bind chemically to the polymeric matrix. Electronic and topographical images showed small crystalline aggregates from AmB crystals on the polymer surface. About 56.6% of AmB was released by the NRL in 120 h. However, 33.6% of this antifungal was delivered in the first 24 h due to the presence of AmB on the polymer surface. The biomaterial's excellent hemo- and cytocompatibility with erythrocytes and human dermal fibroblasts (HDF) confirmed its safety for dermal wound application. Antifungal assay against Candida albicans showed that AmB-NRL presented a dose-dependent behavior with an inhibition halo of 30.0 ± 1.0 mm. Galleria mellonella was employed as an in vivo model for C. albicans infection. Survival rates of 60% were observed following the injection of AmB (0.5 mg.mL-1) in G. mellonella larvae infected by C. albicans. Likewise, AmB-NRL (0.5 mg.mL-1) presented survival rates of 40%, inferring antifungal activity against fungus. Thus, NRL adequately acts as an AmB-sustained release matrix, which is an exciting approach, since this antifungal is toxic at high concentrations. Our findings suggest that AmB-NRL is an efficient, safe, and reasonably priced ($0.15) dressing for the treatment of cutaneous fungal infections.

Revealing anti-fungal potential of plant-derived bioactive therapeutics in targeting secreted aspartyl proteinase (SAP) of Candida albicans: a molecular dynamics approach.

Candida species have established themselves as a major source of nosocomial infections. Increased expression of secreted aspartyl proteinases (SAP5) plays a crucial role in the pathogenesis of Candida species. Phytotherapeutics continue to serve as a viable resource for discovering novel antifungal agents. Hence the main aim of the present investigation is to explore the possible inhibitory role of the selected bioactive molecules against the SAP5 enzyme of C. albicans using in silico approach. Molecular docking and dynamic simulations were utilized to predict the binding affinity of the lead molecules using the AutoDock and Gromacs in-silico screening tools. Results of preliminary docking simulations show that the compounds hesperidin, vitexin, berberine, adhatodine, piperine, and chlorogenic acid exhibit significant interactions with the core catalytic residues of the target protein. The best binding ligands (hesperidin, vitexin, fluconazole) were subjected to molecular dynamics (MD) and essential dynamics of the trajectories. Results of the MD simulation confirm that the ligand-protein complexes became more stable from 20 ns until 100 ns. The calculated residue-level contributions to the interaction energy along a steady simulation trajectory of all three hits (hesperidin (-132.720 kJ/mol), vitexin (-83.963 kJ/mol) and fluconazole (-98.864 kJ/mol)) ensure greater stability of the leads near the catalytic region. Essential dynamics of PCA and DCCM analysis signifies that the binding of hesperidin and vitexin created a more structurally stable environment in the protein target. The overall outcomes of this study clearly emphasize that the bioactive therapeutics found in medicinal herbs may have remarkable scope in managing Candida infection.

Efeito de extratos vegetais de Hamamelis virginiana, Persea americana, Cynara scolymus L e Stryphnodendron barbatiman Msobre a expressão fenotípica dos fatores de virulência em biofilmes de Candida albicans / Effect of Hamamelis virginiana, Persea americana, Cynara scolymus L and Stryphnodendron barbatiman M plant extracts on the phenotypic expression of virulence factors in biofilms of the Candida albicans

Objetivo: Analisar a expressão fenotípica de fatores de virulência em biofilmes de Candida albicans frente a extratos glicólicos de plantas. Material e Métodos: Os biofilmes de Candida albicans (ATCC 18804) obtidos a partir de incubação de 48 horas foram expostos por 5 minutos e 24 horas a diferentes concentrações de extratos glicólicos de Hamamelis virginiana e Persea americana, Cynara scolymus L e Stryphnodendron barbatiman M, a fim de verificar a ação antifúngica da proteinase, fosfolipase e hemolisina. Resultados: Todos os extratos foram eficazes na redução do biofilme. Em contato por 5 minutos. os extratos reduziram 50% do biofilme. Após 24 horas. o extrato de Persea americana apresentou o biofilme em 90%, seguido de Cynara scolymus, que o interrompeu em 85%. Houve mudança na intensidade da proteinase após 5 minutos e 24 horas, com uma atividade enzimática média de 0,69 em comparação com o controle de 0,49. Cynara scolymus foi o extrato com maior concentração média de 100 mg/ml; a intensidade da fosfolipase foi alterada com Stryphnodendron barbatiman sendo mais efetivo em 24 horas em relação ao controle (p< 0,0001). A secreção de hemolisina foi modificada por Hamamelis virginiana (12,5 mg/ml) após 5 minutos de exposição e em 24 horas. todos os extratos foram capazes de causar alterações na secreção. Conclusão: Os extratos testados apresentam potencial antifúngico em biofilmes de Candida albicans, implicando em redução significativa dos fatores de virulência. Assim, estes podem ser indicados como uma ferramenta terapêutica alternativa para reduzir a morbidade dessas infecções, já que em ambos os tempos de exposição investigados, eles foram capazes de reduzir a secreção enzimática do fungo (AU)

Objective: Analyze the phenotypic expression of virulence factors in Candida albicans biofilms against plant glycolicextracts. Material and Methods: The biofilms of Candida albicans (ATCC 18804) obtained from incubation for 48 hours were exposed for 5 minutes and 24 hours to different concentrations of glycolic extracts of Hamamelis virginiana and Persea americana, Cynara scolymus L and Stryphnodendron barbatiman M, in order to verify the antifungal activity of the proteinase, phospholipase and hemolysin. Results: All extracts were effective in reducing biofilm. In contact for 5 minutes. the extracts reduced 50% of the biofilm. After 24 hours, the Persea americanaextract showed the biofilm at 90%, followed by Cynara scolymus, which interrupted it at 85%, There was a change in proteinase intensity after 5 minutes and 24 hours. with an average enzymatic activity of 0.69 compared to the control of 0.49. Cynara scolymus was the extract with the highest mean concentration of 100 mg/ml; the phospholipase intensity was changed with Stryphnodendron barbatiman being more effective in 24 hours compared to the control (p< 0.0001). The hemolysin secretion was modified by Hamamelis virginiana (12.5 mg/ml) after 5 minutes of exposure, and in 24 hours. all extracts were capable to cause changes in secretion. Conclusion: The tested extracts have antifungal potential in Candida albicans biofilms, implying a significant reduction in virulence factors. Thus, these can be indicated as an alternative therapeutic tool to reduce the morbidity of these infections, as in both investigated exposure times. they were able to reduce theenzymatic secretion of the fungus (AU)

Evaluation of Physical Properties of Denture Base Resins Containing Silver Nanoparticles of Aloe barbadensis Miller, Morinda citrifolia, and Boesenbergia rotunda and Its Anti-microbial Effect: An In Vitro Study.

Introduction The denture bases fabricated from polymethylmethacrylate (PMMA) have some disadvantages, such as surface prone to microbial growth and biofilm accumulation, which contributes to the onset and dissemination of infections among denture wearers. Therefore, the purpose of this in vitro study was to evaluate the flexural strength, hardness, and antimicrobial effect of denture base resin incorporated with 0.05% and 0.1% silver nanoparticles (AgNPs) of Aloe barbadensis miller (aloe vera), Morinda citrifolia (noni), and Boesenbergia rotunda (finger root). Materials and methods A total of 84 PMMA samples were used and were divided into three groups. Flexural strength tests were performed on Group 1 PMMA blocks. Group 2 involved hardness testing of PMMA blocks, whereas Group 3 involved antimicrobial activity. Each group was subsequently split into seven subgroups with differing concentrations of AgNPs: Sub Group 1: control (no AgNPs), Sub Group 2: 0.05% aloe vera AgNPs, Sub Group 3: 0.1% aloe vera AgNPs, Sub Group 4: 0.05% noni AgNPs, Sub Group 5: 0.1% of noni AgNPs, Sub Group 6: 0.05% finger root AgNPs, and Sub Group 7: 0.1% finger root AgNPs. The flexural strength was evaluated using a universal testing machine (Instron 8801). Surface hardness was measured using a Vickers tester (Tukon 1102). For the antimicrobial activity analysis, the samples were incubated in a suitable culture broth containing Candida albicans for 24 hours. Microbial colony count (colony-forming unit (CFU)/mL) was estimated to evaluate the microbial adhesion to the surface of the denture base materials. Statistical analysis The flexural strength, hardness, and CFU between the groups were analyzed using one-way analysis of variance (ANOVA) followed by multiple comparisons with Tukey's honest significant difference (HSD) test (α=0.05). The level of statistical significance was determined at p<0.05. Results It was observed that the mean flexural strength was maximum in PMMA incorporated with 0.05% of aloe vera AgNPs and least in PMMA incorporated with 0.1% noni AgNPs. It was seen that a steady loss in flexural strength is observed from 0.05% to 0.1%. The mean hardness was maximum in PMMA incorporated with 0.1% of noni AgNPs and least in PMMA incorporated with 0.05% aloe vera AgNPs. It was also found that the hardness was directly proportional to the number of nanoparticles. With an increase in the weight percentage of nanoparticles, a steady increase in hardness was seen in all the test groups. In our study, the results showed that finger root 0.1% showed the least CFU with a significant reduction of C. albicans adherence; therefore, it indicates higher anti-fungal activity. Aloe vera 0.05% showed the lowest inhibition of C. albicans, suggesting the least anti-fungal activity. Conclusion Within the limitations of this study, It can thus be concluded that the addition of AgNPs incorporated with plant extracts of Aloe barbadensis miller (aloe vera), Morinda citrifolia (noni), and Boesenbergia rotunda (finger root) can alter the flexural strength, hardness, and microbial adhesion of PMMA. In our study, it can be concluded that flexural strength increases with the addition of AgNPs of 0.5% concentration after which a steady loss is seen. However, the hardness and antimicrobial activity increased with an increase in the concentration of AgNPs in all three plant extracts.

Histatin-5 interacts with cellular copper to promote antifungal activity against Candida albicans.

Histatin-5 (Hist-5) is an antimicrobial peptide found in human saliva that functions to defend the oral cavity from microbial infections, such as those caused by the fungal pathogen Candida albicans (C. albicans). Hist-5 can bind Cu in multiple oxidation states, Cu2+ and Cu+in vitro, and supplemental Cu2+ has been shown to improve the fungicidal activity of the peptide against C. albicans in culture. However, the exact role of Cu on the antifungal activity of Hist-5 and whether direct peptide-Cu interactions occur intracellularly has yet to be fully determined. Here, we used a combination of fluorescence spectroscopy and confocal microscopy experiments to show reversible Cu-dependent quenching of a fluorescent Hist-5 analogue, Hist-5*, indicating a direct interaction between Hist-5 and intracellular Cu. X-ray fluorescence microscopy images revealed peptide-induced changes to cellular Cu distribution and cell-associated Cu content. These data support a model in which Hist-5 can facilitate the hyperaccumulation of Cu in C. albicans and directly interact with Cu intracellularly to increase the fungicidal activity of Hist-5.

A Systematic Evaluation of Curcumin Concentrations and Blue Light Parameters towards Antimicrobial Photodynamic Therapy against Cariogenic Microorganisms.

Dental caries is a highly preventable and costly disease. Unfortunately, the current management strategies are inadequate at reducing the incidence and new minimally invasive strategies are needed. In this study, a systematic evaluation of specific light parameters and aqueous curcumin concentrations for antimicrobial photodynamic therapy (aPDT) was conducted. Aqueous solutions of curcumin were first prepared and evaluated for their light absorbance after applying different ~56 mW/cm2 blue light treatments in a continuous application mode. Next, these same light treatments as well as different application modes were applied to the curcumin solutions and the molar absorptivity coefficient, reactive oxygen species (ROS) release, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) for Streptococcus mutans and the MIC and minimum fungicidal concentration (MFC) for Candida albicans were measured. After up to 1 min of light treatment, the molar absorptivity of curcumin when added to culture media was lower than that for water only; however, at higher energy levels, this difference was not apparent. There was a noted dependence on both ROS type and cariogenic microorganism species on the sensitivity to both blue light treatment and application mode. In conclusion, this study provides new information towards improving the agonistic potential of aPDT associated with curcumin against cariogenic microorganisms.

Antimicrobial and antibiofilm effects of shikonin with tea tree oil nanoemulsion against Candida albicans and Staphylococcus aureus.

The current work aims to develop a shikonin and tea tree oil loaded nanoemulsion system stabilized by a mixture of GRAS grade surfactants (Tween 20 and monoolein) and a cosurfactant (Transcutol P). This system was designed to address the poor aqueous solubility and photostability issues of shikonin. The authenticity of shikonin employed in this study was confirmed using nuclear magnetic resonance (NMR) spectroscopy. The optimized nanoemulsion exhibited highly favorable characteristics in terms of zeta potential (-23.8 mV), polydispersity index (0.216) and particle size (22.97 nm). These findings were corroborated by transmission electron microscopy (TEM) micrographs which confirmed the spherical and uniform nature of the nanoemulsion globules. Moreover, attenuated total reflectance (ATR) and X-ray diffraction analysis (XRD) analysis affirmed improved chemical stability and amorphization, respectively. Photodegradation studies were performed by exposing pure shikonin and the developed nanoemulsion to ultraviolet light for 1 h using a UV lamp, followed by high performance liquid chromatography (HPLC) analysis. The results confirmed that the developed nanoemulsion system imparts photoprotection to pure shikonin in the encapsulated system. Furthermore, the research investigated the effect of the nanoemulsion on biofilms formed by Candida albicans and methicillin resistant Staphylococcus aureus (MRSA). Scanning electron microscopy, florescence microscopy and phase contrast microscopy unveiled a remarkable reduction in biofilm area, accompanied by disruptions in the cell wall and abnormalities on the cell surface of the tested microorganisms. In conclusion, the nanoencapsulation of shikonin with tea tree oil as the lipid phase showcased significantly enhanced antimicrobial and antibiofilm potential compared to pure shikonin against resistant strains of Candida albicans and Staphylococcus aureus.

The Impact of Berberine Loaded Selenium Nanoparticles on K. pneumoniae and Candida albicans Antibiotics Resistance Isolates.

This study aimed to investigate the antibacterial and antifungal activities of selenium nanoparticles (SeNPs) and berberine (BBR) despite antibiotic resistance against Klebsiella pneumoniae and Candida albicans. Cells of K. pneumoniae and C. albicans were treated with solutions of different concentrations of each bare SeNPs, BBR, and BBR-loaded SeNPs (BLS) using the disk diffusion method. The results indicated that the activities of SeNPs, BBR, and BLS were statistically significant (P<0.05) when the concentration of all agents increased. Moreover, it was found that BLS had a statistically significant effect against K. pneumoniae and C. albicans, compared to SeNPs and BBR alone (P<0.05). The largest zones of inhibition of SeNPs were 14 and 16 mm toward K. pneumoniae and C. albicans, respectively, at the concentration of 20 Mml, compared to the concentrations of 10 and 15 Mml. Furthermore, BBR showed a maximum zone of inhibition at the concentration of 1,200 mg (15 mm for K. pneumoniae and 18 mm for C. albicans) and it was statistically significant in comparison with other concentrations of 400 and 800 mg. In addition, the BLS underwent a statistically significant increase (P<0.05) when the concentration increased and it registered a large zone of inhibition of 22 and 25 mm against K. pneumoniae and C. albicans, respectively, at 20 Mml of SeNPs: 1,200 mg BBR, compared to 10 Mml of SeNPs: 400 mg BBR and 15 Mml of SeNPs: 800 mg BBR. Based on the results of the current study, there was a statistically synergistic effect of BBR-loaded SeNPs, compared to that of BBR and Se nanoparticles, only in the case of both K. pneumoniae and C. albicans. This study is promising as a blueprint for the enhancement of weak antimicrobial agents and their return to their previous role as antibiotics.