Candida Strains Research Articles

Enhancing the quality and safety of Nocellara del Belice green table olives produced using the Castelvetrano method

The Castelvetrano method is the most widely used among the various table olive processing styles in Sicily. After debittering, the product is stored at low temperatures to prevent the growth of undesirable microorganisms. In an effort to enhance the production process, yeast isolates underwent genotypic characterization and technological screening. The screening process identified two yeast strains Candida norvegica OC10 and Candida boidinii LC1, which can grow at low temperatures and tolerate high pH values (up to 10) and salinity [10% (w/v)]. During the monitoring period, the inoculated trials showed limited presence of spoilage/pathogenic microorganisms. Additionally, the yeasts limited oxidative phenomena and softening of the drupes. The organic compounds detected were higher in the inoculated trials than in the control, and cold storage induced aromatic decay, which was less pronounced in the trial inoculated with C. norvegica. Sensory analysis revealed that the inoculated trials scored higher in sweetness, hardness and crispness.

Vaginal prevention of Candida albicans: synergistic effect of lactobacilli and mannan oligosaccharides (MOS)

Vulvovaginal candidiasis (VVC) affects approximately 30–50% of women at least once during their lifetime, causing uncomfortable symptoms and limitations in their daily quality of life. Antifungal therapy is not very effective, does not prevent recurrencies and usually causes side effects. Therefore, alternative therapies are urgently needed. The goal of this work was to investigate the potential benefits of using mannan oligosaccharides (MOS) extracts together with a Lactobacillus sp. pool, composed by the most significant species present in the vaginal environment, to prevent infections by Candida albicans. Microbial growth of isolated strains of the main vaginal lactobacilli and Candida strains was assessed in the presence of MOS, to screen their impact upon growth. A pool of the lactobacilli was then tested against C. albicans in competition and prophylaxis studies; bacterial and yeast cell numbers were quantified in specific time points, and the above-mentioned studies were assessed in simulated vaginal fluid (SVF). Finally, adhesion to vaginal epithelial cells (HeLa) was also evaluated, once again resorting to simultaneous exposure (competition) or prophylaxis assays, aiming to measure the effect of MOS presence in pathogen adherence. Results demonstrated that MOS extracts have potential to prevent vaginal candidiasis in synergy with vaginal lactobacilli, with improved results than those obtained when using lactobacilli alone.Key pointsPotential benefits of MOS extracts with vaginal lactobacilli to prevent C. albicans infections.MOS impacts on growth of vaginal lactobacilli pool and C. albicans in SVF.MOS extracts in synergy with L. crispatus inhibit C. albicans adhesion in HeLa cells.Graphical

Virulence profile of Candida spp. isolated from an anaerobic biodigester supplied with dairy cattle waste

Anaerobic biodigesters play a crucial role in enhancing animal waste management. However, the presence of pathogens in the biodigestion process poses a significant concern. Candida spp., a widespread fungus known for its opportunistic nature and adaptability to diverse environmental conditions, including reciprocal transmission between humans and animals, is one such pathogen of concern. Therefore, it is imperative to assess the virulence profile of Candida spp. originating from anaerobic biodigestion processes. Here we demonstrate that strains isolated from the biodigestion process of dairy cattle waste exhibit noteworthy virulence mechanisms, surpassing the virulence of clinical control strains. After we identified strains from affluent, effluent, and biofertilizer, we observed that all analyzed isolates produced biofilm. Additionally, a substantial proportion of these isolates demonstrated phospholipase production, while only a few strains exhibited protease production. Furthermore, all strains exhibited resistance or dose-dependent responses to amphotericin B and itraconazole, with the majority displaying resistance to fluconazole. In the in vivo test, we observed a significant correlation (p < 0.05) between the LT50 and biofilm formation as well as hyphae/pseudohyphae production. Additionally, some isolates demonstrated a quicker nematode-killing capacity compared to clinical controls. Our findings underscore the considerable pathogenic potential of certain Candida species present in the dynamics of anaerobic biodigestion. Importantly, the anaerobic biodigester system did not eliminate Candida strains from dairy cattle waste, highlighting the need for caution in utilizing biodigester products. We advocate for further studies to explore the virulence of other microorganisms in various animal production contexts. Furthermore, our results emphasize the urgency of enhancing waste treatment methods to effectively eliminate pathogens and curb their potential dissemination.

Structure-activity relationship of anticancer and antiplasmodial gold bis(dithiolene) complexes.

Monoanionic gold bis(dithiolene) complexes were recently shown to display activity against ovarian cancer cells, Gram-positive bacteria, Candida strains and the rodent malaria parasite, P. berghei. To date, only monoanionic gold(III) bis(dithiolene) complexes with a thiazoline backbone substituted with small alkyl chains have been evaluated for biomedical applications. We now analyzed the influence of the length and the hydrophobicity vs. hydrophilicity of these complexes' alkyl chain on their anticancer and antiplasmodial properties. Isomer analogues of these monoanionic gold(III) bis(dithiolene) complexes, this time with a thiazole backbone, were also investigated in order to assess the influence of the nature of the heterocyclic ligand on their overall chemical and biological properties. In this report we present the total synthesis of four novel monoanionic gold(III) bis(dithiolene) complexes with a long alkyl chain and a polyoxygenated (PEG) chain aiming to improve their solubility and biological properties. Our results showed that the complexes with a PEG chain showed promising anticancer and antiplasmodial activities beside improved solubility, a key parameter in drug discovery and development.

Candidaemia: A 9-Year Retrospective Analysis of Epidemiology and Antimicrobial Susceptibility in Tertiary Care Hospitals in Western China.

This investigation endeavors to scrutinize the resistance profiles to antifungal agents, alongside the clinical distribution of Candida isolates that yielded positive results in blood cultures at Suining Central Hospital spanning the years 2015 to 2023. The objective is to provide crucial epidemiological insights that may aid in early clinical intervention and judicious deployment of antifungal therapies. This retrospective analysis analyses data on 182 different Candida strains with positive clinical blood cultures obtained from the Microbiology Laboratory of Suining Central Hospital over a period of nine consecutive years. The study involved identification of Candida species and assessment of resistance patterns to fungal drugs. Our analysis revealed that the median age of patients diagnosed with Candidaemia from the 182 strains was 62 years, with a distribution of 63.7% females and 36.3% males. Within the cohort of 182 Candida strains, Candida albicans constituted 32.4%, while non-albicans Candida species comprised 67.6% of the cases. Specifically, Candida tropicalis represented 37.4%, Candida glabrata 12.1%, Candida parapsilosis 11.0%,Candida guilliermondii 3.8%, and both Candida krusei and Candida Dublin accounted for 1.6% each. These Candida species were predominantly identified in intensive care units (ICU), hematology, gastroenterology, neurology centers, and endocrine metabolism units. The findings of this investigation suggest a shift in the prevalence of non-Candida albicans species, notably C. tropicalis, as the predominant cause of Candidaemia at Suining Central Hospital, surpassing C. albicans. Although instances of antifungal resistance are infrequent, there has been a notable rise in resistance to azoles. This study provides important insights into the local epidemiology, which will be essential for informing the selection of empirical antifungal therapy and contributing to the global surveillance of antifungal resistance.

Coriandrum sativum L., essential oil as a promising source of bioactive compounds with GC/MS, antioxidant, antimicrobial activities: in vitro and in silico predictions.

Introduction: Coriandrum sativum L. essential oil (CS-EO) is being evaluated in vitro for its antioxidant and antimicrobial properties, and its volatile compounds are to be identified as part of this exploratory study. Methods: The processes underlying the in vitro biological properties were explained using in silico simulations, including drug-likeness prediction, molecular docking, and pharmacokinetics (absorption, distribution, metabolism, excretion, and toxicity-ADMET). Chemical screening of CS-EO was conducted using gas chromatography-mass spectrometry (GC-MS). Five in vitro complementary techniques were used to assess the antioxidant activity of CS-EO: reducing power (RP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonate) (ABTS) radical scavenging activity, β-Carotene bleaching test (BCBT), and phosphomolybdenum assay (TAC). Results: According to GC-MS analysis, linalool (59.04%), γ-Terpinene (13.02%), and α-Pinene (6.83%) are the main constituents of CS-EO. Based on the in vitro antioxidant assay results, CS-EO has been found to have a superior antioxidant profile. Its estimated scavenging rates for ABTS+ are 0.51 ± 0.04mg/mL, BCBT is 9.02 ± 0.01mg/mL, and CS-EO is 1.52 ± 0.14mg/mL. C. sativum demonstrated 6.13 ± 0.00μg/mL for reducing power and 213.44 ± 0.45mg AAE/mL for total antioxidant activity. The in vitro antimicrobial activity of CS-EO was assessed against five strains, including two gram-positive bacteria, two gram-negative bacteria, and one fungal strain (Candida albicans). Significant antibacterial and antifungal activities against all strains were found using the disc-diffusion assay, with zones of inhibition larger than 15mm. The microdilution test highlighted the lowest MIC and MBC values with gram-positive bacteria, ranging from 0.0612 to 0.125% v/v for MIC and 0.125% v/v for MBC. The fungal strain's MFC was 1.0% v/v and its MIC was measured at 0.5%. Based on the MBC/MIC and MFC/MIC ratios, CS-EO exhibits bactericidal and fungicidal activity. The ADMET study indicates that the primary CS-EO compounds are good candidates for the development of pharmaceutical drugs due to their favorable pharmacokinetic properties. Conclusion: These results point to a potential application of this plant as a natural remedy and offer empirical backing for its traditional uses. It is a promising environmentally friendly preservative that can be used extensively in the food and agricultural industries to prevent aflatoxin contamination and fungal growth in stored goods.

Photocatalytic and Antimicrobial Properties of ZnO and Mg-Doped ZnO Nanoparticles Synthesized Using Lupinus albus Leaf Extract.

Dye effluents discharged from various industries contribute to environmental contamination, making their treatment highly necessary. Infectious diseases also pose a threat to public health worldwide. Nanomaterials have promising features and are potential candidates for overcoming the problems of drug resistance in microbes and environmental pollution. Therefore, this study aimed to synthesize zinc oxide (ZnO) and magnesium-doped zinc oxide (Mg-doped ZnO) nanoparticles (NPs) using the plant extract of Lupinus albus for applications in photocatalysis and antimicrobial activity. A sample of Lupinus albus leaves was collected from Motta, in the eastern Gojjam zone of Ethiopia. The leaves were air-dried and then ground into a powder. The powdered plant material was extracted using distilled water. The ZnO and Mg-doped ZnO NPs were synthesized using 0.1 M Zn(NO3)2·6H2O, 7.5% 0.1 M Mg(NO3)2.6H2O, and 10 mL of the leaf extract. The nanoparticles (NPs) were characterized using UV-vis, FT-IR, XRD, and SEM. The average crystallite sizes of ZnO and Mg-doped ZnO NPs were determined using the Debye-Scherrer formula and were found to be 28.1 and 34.4 nm, respectively. The antimicrobial activity of the synthesized NPs was evaluated against four bacterial strains (Escherichia coli, Bacillus cereus, Salmonella typhi, and Staphylococcus aureus) and one fungal strain (Candida albicans) by using the agar disk diffusion method. The Mg-doped ZnO NPs exhibited significant antimicrobial activity, with a maximum zone of inhibition measuring 24 and 22 mm against Escherichia coli and Salmonella typhi, respectively. The photocatalytic activity of ZnO and Mg-doped ZnO NPs was investigated by studying the degradation of methylene blue (MB) dye under sunlight irradiation for 120 min. The results showed that Mg-doped ZnO NPs exhibited higher photocatalytic activity (99.6%) than ZnO NPs (94.1%). In conclusion, the synthesized NPs could serve as viable alternatives for antimicrobial drugs and photocatalysts to mitigate the pollution of the environment caused by organic dyes.

The Combination of 3-Hydrazinoquinoxaline-2-Thiol with Thymoquinone Demonstrates Synergistic Activity Against Different Candida Strains.

Candida is the primary cause of invasive fungal disease, candidiasis, especially in developed nations. The increasing resistance observed in multiple antibiotics, coupled with the prolonged process of creating new antibiotics from the ground up, emphasizes the urgent requirement for innovative methods and new compounds to combat Candida infections. Employing a treatment strategy that combines antibiotics can improve efficacy, broaden the spectrum of targeted fungal, and reduce the chances of resistance emergence. This approach shows potential in tackling the escalating problem of antibiotic resistance. The objective of this research is to explore the potential synergistic effects of combining 3-hydrazinoquinoxaline-2-thiol and thymoquinone against a variety of Candida isolates. This investigation aims to offer an understanding of the collective antimicrobial action of these compounds. Broth microdilution was utilized to assess the Minimum Inhibitory Concentrations (MICs) of 3-hydrazinoquinoxaline-2-thiol and thymoquinone for 22 clinical Candida isolates. Following this, a checkerboard assay was employed to analyze the interaction between 3-hydrazinoquinoxaline-2-thiol and thymoquinone, with a specific focus on the Fractional Inhibitory Concentration Index (FICI). The MICs of thymoquinone and 3-hydrazinoquinoxaline-2-thiol were determined for 22 clinical Candida strains, with thymoquinone exhibiting MICs ranging from 64 to 8 µg/mL, and 3-hydrazinoquinoxaline-2-thiol displaying MICs varying from 64 to 8 µg/mL. Notably, the combination of 3-hydrazinoquinoxaline-2-thiol and thymoquinone resulted in a synergistic effect, leading to a significant reduction in MICs, with reductions of up to 64-fold with FICI below 0.5 against tested strains. The prospect of using 3-hydrazinoquinoxaline-2-thiol in combination with thymoquinone as an effective solution against Candida looks encouraging. Nevertheless, to validate its practical applicability, additional comprehensive testing and experiments are imperative.

CHANGING PATTERN OF NON ALBICANS CANDIDEMIA: OCCURENCE AND SUSCEPTIBILITY PROFILE IN AN INDONESIAN SECONDARY TEACHING HOSPITAL.

In recent years, bloodstream infections due to non-albicans Candida species have been reported significantly among hospitalized patients, mainly among immunocompromised patients with high morbidity and mortality rates. A better understanding and awareness regarding the shift of Candida albicans flora to non-albicans Candida species is essentially important to improve treatment outcomes. In this study, we evaluated the distribution of non-albicans Candida species and their susceptibility to various antifungals among candidemia patients. A total of 123 confirmed Candida blood culture episodes from January 2011 to June 2022 were analyzed by retrospective laboratory-based observation. Candida species identity and the in vitro activity against antifungal drugs determined by guidelines from the Clinical and Laboratory Standard Institute (CLSI). Most candidemia were caused by non-albicans Candida species, including Candida parapsilosis (37.4%), Candida tropicalis (17.1%), Candida glabrata (13.0%), Candida guilliermondii (3.2%) and others (4.8%). Meanwhile Candida albicans was found in 24.4% of cases. Among the patients, 57.7% were males and 68.3% were admitted to critical care with an age range of ≤ 28 days and 90 years. The pattern of in vitro susceptibility showed that 91.9% of the Candida strains were susceptible to amphotericin B, 89.3% to flucytosine, 97.3% to fluconazole, 98.3% to voriconazole, and 97.9% to echinocandins. Antifungal drug resistance was rare in our observation. The wide range of antifungal activities encourages management to carry out epidemiological surveillance in order to follow the dynamics of candidemia and influence the choice of therapeutic management for at-risk patients.

Limonene synergistically augments fluconazole susceptibility in clinical Candida isolates from cleft lip and palate patients.

Cleft lip and palate (CLP) patients are prone to Candida infections (oral thrush) mainly due to poor oral hygiene, repetitive surgeries, and orthodontic procedures. This study was undertaken to evaluate the antifungal efficacy of limonene against clinical Candida isolates from CLP patients. The antifungal efficacy of limonene was studied alone and in combination with fluconazole (FLC) against six standards, twenty nine FLC sensitive, and three FLC resistant clinical strains using broth dilution, checkerboard microdilution, agar disk diffusion, growth curves, and spot assays. This nontoxic monoterpene gave low minimum inhibitory concentration (MIC) values of 300-375 µg/mL and 500-520 µg/mL for FLC susceptible and FLC resistant strains, respectively. It showed synergistic interaction with FLC in all clinical and standard Candida strains (fractional inhibitory concentration (FIC) index ≤0.5). Significant chemosensitization of FLC was observed even against resistant clinical isolates. Complete suppression of fungal growth was observed when using combinations. Negligible toxicity, easy availability, and potent antifungal properties suggest that limonene and FLC combinations in appropriate doses can make excellent antifungal mouthwashes during CLP treatment pre and post surgery. Impending in vivo studies are needed to validate the present data.

Optimization of Antioxidant and Antimicrobial Activities by Fractionation of Artemisia judaica subsp. sahariensis Crude Extract from Ahaggar (Algerian Arid Region): UPLC-ESI-MS/MS Analysis of Fractions

Background: In recent years, medicinal plants have received considerable attention due to the search for novel bioactive compounds. In this optic, we have been interested in Artemisia judaica subsp. sahariensis, a Saharan species widely used in phytotherapy by the Tuaregs of the Ahaggar. Objective: This study aims to evaluate and optimize the biological activities of this plant in order to valorize its bioactive compounds. Methods: For this purpose, an extraction with methanol (70%) was carried out, then a liquid-liquid fractionation, using solvents with increasing polarity: diethyl ether, ethyl acetate, n-butanol and water. We realized an analysis of phenols, flavonoids and evaluation of antioxidant and antimicrobial activities in addition to the UPLC-ESI-MS/MS analysis of the fractions. Results: The reducing effect was proportional to the solvent polarity. The crude extract gave the best reducing power (17.55 ± 3.06 μg/mL), better phenols and flavonoids contents (20.35 ± 0.5 mgGAE/gTDM), (10.35 ± 0.56 mgGAE/gTDM) respectively compared to its fractions. The DPPH (2,2-Diphenyl-1-Picrylhydrazyl) radical scavenging assay showed that the ethyl acetate fraction was the most active with the lowest IC50 value (inhibitory concentration to 50% of DPPH) (41.43 ± 0.24 μg/ml) followed by n-butanol (58.53 ± 0.20 μg/mL), diethyl ether (135.07 ± 6.18 μg/mL) and aqueous (226.41 ± 1.51 μg/mL) fractions (p &lt;0.0001). Moreover, hydromethanolic extract gave an IC50 value of 114.05 ± 3.37 μg/mL. The antimicrobial effect was observed on all clinical multiresistant bacteria tested except Klebsiella pneumoniae, which was resistant. The most important effect was observed by the ethyl acetate fraction against the fungal strain Candida albicans. Various phenolic acids and flavonoids (flavones, flavonols, flavanones) were detected and could be responsible for these bioactivities. Conclusion: We can conclude that liquid-liquid extraction with solvents of increasing polarity plays a major role in optimizing the biological activity of this plant, which contains polyphenols and can therefore be valued as a source of natural antioxidants and antimicrobials.

Two cobaltous PCPs: rapid catalytic degradation of POPs coupled with remarkable antibacterial and antifungal properties.

In this work, we report the synthesis of two cobalt-based porous coordination polymers (PCPs): [Co3(BTC)2(H2O)12]n (1) and [Co3(BTC)2(DMP)8]n (2) [where BTC = 1,3,5-benzenetricarboxylate and DMP = 3,5-dimethylpyrazole]. These compounds were characterized using a range of physicochemical techniques, including UV-DRS, FT-IR, SCXRD, PXRD, TGA, and FE-SEM/EDX. The synthesized PCPs effectively catalyzed the degradation of various persistent organic pollutants (POPs) rapidly, which includes both cationic and anionic dyes such as Malachite Green (MG), Methylene Blue (MB), Indigo Carmine (IC), Methyl Orange (MO), Orange G (OG), and Eriochrome Black T (EBT). They also have excellent efficacy in degrading nitroaromatics viz. 4-nitrophenol (4-NP), 2,4-dinitrophenol (2,4-DNP), and 2,4,6-trinitrophenol (2,4,6-TNP) in the presence of NaBH4 as a reductant. In addition, these PCPs exhibited remarkable antibacterial and antifungal properties, demonstrating strong activity against bacterial strains such as Escherichia coli, Staphylococcus aureus, and Bacillus subtilis, as well as the fungal strain Candida albicans. These results indicate that these two PCPs have considerable potential for catalyzing the rapid degradation of POPs, while also showing promising biological activities, offering substantial opportunities for future research.

Antimicrobial mechanism of Limosilactobacillus fermentum SHY10 metabolites against pickle film-producing strain by metabolomic and transcriptomic analysis

The antimicrobial mechanism of Limosilactobacillus fermentum SHY10 metabolites on the pickle film-producing strain Candida parapsilosis B7 was investigated in this study. The results showed that SHY10 metabolites mainly consisted of peptides, alkaloids, nucleic acids, hormones and transmitters, and sterol lipids. Peptides and alkaloids accounted respectively for 15.5% and 22.7% of the total. The SHY10 metabolites induced pits on the cell membrane and death of film-producing strain, which were evidenced by scanning electron microscope and fluorescence. Metabolomic results showed that SHY10 metabolites had the most significant effect on the purine metabolic pathway of Candida parapsilosis B7. Transcriptome results showed that 505 genes of Candida parapsilosis B7 related to peroxisome, α-linolenic acid metabolism, ubiquinone and other terpenoid quinone biosynthesis were remarkably changed with the presence of SHY10 metabolites. The expression of PEX 3, PEX 12, ACOX 1 and wrbA determined by qRT-PCR were consistent with the transcriptome results. In summary, the SHY10 metabolites changed the expression of PEX 3, PEX 12, ACOX 1 and wrbA and affected peroxisome, α-linolenic acid metabolism, ubiquinone and other terpenoid quinone biosynthesis pathways, and eventually led to the death of Candida parapsilosis B7.

ROS mediated anticandidal efficacy of 3-Bromopyruvate prevents vulvovaginal candidiasis in mice model.

Candidal infections, particularly vulvovaginal candidiasis (VVC), necessitate effective therapeutic interventions in clinical settings owing to their intricate clinical nature and elusive understanding of their etiological mechanisms. Given the challenges in developing effective antifungal therapies, the strategy of repurposing existing pharmaceuticals has emerged as a promising approach to combat drug-resistant fungi. In this regard, the current study investigates molecular insights on the anti-candidal efficacy of a well-proven anticancer small molecule -3-bromopyruvate (3BP) against three clinically significant VVC causing Candida species viz., C. albicans, C. tropicalis and C. glabrata. Furthermore, the study validates 3BP's therapeutic application by developing it as a vaginal cream for the treatment of VVC. 3BP exhibited phenomenal antifungal efficacy (killing >99%) with minimum inhibitory concentrations (MIC) and minimum fungicidal concentrations (MFC) of 256 μg/mL against all tested Candida spp. Time killing kinetics experiment revealed 20 min as the minimum time required for 3BP at 2XMIC to achieve complete-killing (99.9%) in all Candida strains. Moreover, the ergosterol or sorbitol experiment explicated that the antifungal activity of 3BP does not stem from targeting the cell wall or the membrane component ergosterol. Instead, 3BP was observed to instigate a sequence of pre-apoptotic cascade events, such as phosphatidylserine (PS) externalization, nuclear condensation and ROS accumulations, as evidenced by PI, DAPI and DCFH-DA staining methods. Furthermore, 3BP demonstrated a remarkable efficacy in eradicating mature biofilms of Candida spp., achieving a maximum eradication level of 90%. Toxicity/safety profiling in both in vitro erythrocyte lysis and in vivo Galleria mellonella survival assay authenticated the non-toxic nature of 3BP up to 512 μg/mL. Finally, a vaginal cream formulated with 3BP was found to be effective in VVC-induced female mice model, as it significantly decreasing fungal load and protecting vaginal mucosa. Concomitantly, the present study serves as a clear demonstration of antifungal mechanistic action of anticancer drug -3BP, against Candida species. This finding holds significant potential for mitigating candidal infections, particularly VVC, within healthcare environments.

Phenol Biodegradation by Free and Immobilized Acinetobacter calcoaceticus K5 and Candida tropicalis YM2 Isolated from Persian Gulf

Phenols exhibit high solubility in water, leading to their potential to contaminate significant volumes of freshwater, wastewater, groundwater, oceans, and soil. The primary objective of this study is to isolate and identify bacterial and yeast isolates with optimal phenol degradation capabilities from Persian Gulf. Sea water and sediment samples were collected to isolate bacterial and yeast isolates, which were then evaluated for their ability to degrade phenol both in their single-cell form and when encapsulated in chitosan and alginate. The phenol-degrading strains were quantified using colony-forming unit (CFU) and most probable number (MPN) methods. The most promising microorganisms were selected and identified using phenotypic and polymerase chain reaction techniques. The selected isolates were immobilized in alginate and chitosan carriers, and their bioremediation potential was assessed at different phenol concentrations. The removal of phenol by the isolates was confirmed using Gas Chromatography. Through molecular techniques, Acinetobacter calcoaceticus K5 and Candida tropicalis YM2 were identified as the most efficient phenol-degrading strains. Acinetobacter calcoaceticus K5 exhibited the highest growth at phenol concentrations of 200 and 300 ppm, while Candida tropicalis YM2 showed optimal growth at a concentration of 700 pp. In case of Acinetobacter calcoaceticus, chitosan immobilization and a phenol concentration of 500 ppm proved to be the best conditions for phenol bioremediation. In the case of Candida tropicalis YM2, the highest percentage of phenol removal was achieved using the chitosan carrier at a concentration of 1000 ppm. Comparing the immobilized strains to their free counterparts, it was observed that the stabilized bacteria exhibited greater phenol removal efficiency, particularly at a concentration of 500 ppm, with a significant difference between the two conditions. This study demonstrates that the novel strains Acinetobacter calcoaceticus K5 and Candida tropicalis YM2 are efficient strains for the bioremediation of various phenol-contaminated seawater and this is the first report to show such rapid phenol degradation by these organisms isolated from sediment and seawater samples collected from Persian Gulf.

Formulation and characterization of polyvinyl alcohol/chitosan composite nanofiber co-loaded with silver nanoparticle & luliconazole encapsulated poly lactic-co-glycolic acid nanoparticle for treatment of diabetic foot ulcer

Chronic wounds are prone to fungal infections, possess a significant challenge, and result in substantial mortality. Diabetic wounds infected with Candida strains are extremely common. It can create biofilm at the wound site, which can lead to antibiotic resistance. As a result, developing innovative dressing materials that combat fungal infections while also providing wound healing is a viable strategy to treat infected wounds and address the issue of antibiotic resistance. Present work proposed anti-infective dressing material for the treatment of fungal strains Candida-infected diabetic foot ulcer (DFU). The nanofiber was fabricated using polyvinyl Alcohol/chitosan as hydrogel base and co-loaded with silver nanoparticles (AgNP) and luliconazole-nanoparticles (LZNP) nanoparticles, prepared using PLGA. Fabricated nanofibers had pH close to target area and exhibited hydrophilic surface suitable for adhesion to wound area. The nanofibers showed strong antifungal and antibiofilm properties against different strains of Candida; mainly C. albicans, C. auris, C. krusei, C. parapsilosis and C. tropicalis. Nanofibers exhibited excellent water retention potential and water vapour transmission rate. The nanofibers had sufficient payload capacity towards AgNP and LZNP, and provided controlled release of payload, which was also confirmed by in-vivo imaging. In-vitro studies confirmed the biocompatibility and enhanced proliferation of Human keratinocytes cells (HaCaT). In-vivo studies showed accelerated wound closure by providing ant-infective action, supporting cellular proliferation and improving blood flow, all collectively contributing in expedited wound healing.

Characterizing a novel antimicrobial molecule effective for drug-resistant pathogens and bacterial biofilm that augments keratinocyte migration

Hypervalent silver complexes, containing Ag(II) and Ag(III), have recently gained interest due to their potent antimicrobial efficacy. This work explores the synthesis and antimicrobial activity of a novel tribasic silver bisperiodate tetrahydrate (K3AgBP) complex containing both silver and iodine in hypervalent states: Ag(III) and I(VII). The antimicrobial efficacy of K3AgBP was evaluated and compared to hypervalent silver oxynitrate (Ag7NO11) and periodate salts, and conventional antibiotic drug compounds against methicillin-susceptible (MSSA) and resistant Staphylococcus aureus (USA-300 MRSA), susceptible (PAO1) and carbapenem-resistant blaVIM-2-positive (VIM-2) Pseudomonas aeruginosa, and drug-resistant strains of Candida. Minimum inhibitory concentrations for K3AgBP were equal or lower than silver oxynitrate and periodate salts for all species tested and significantly lower than antibiotics against MRSA, VIM-2 and antifungal efficacy against clinically isolated resistant C. albicans (Ca3917) was also shown. Hypervalent silvers, impregnated in a dressing at 0.4 mg Ag/cm2, were evaluated against 72-hour established biofilm. K3AgBP more effectively (P < 0.05) disrupted and eradicated S. aureus and P. aeruginosa biofilm, 6.72 ± 0.23 and 6.81 ± 0.23 log reduction within 4-hours and 2-hours respectively, versus 4.33 ± 0.23 and 4.97 ± 0.68 log CFU/ml respectively for silver oxynitrate. To assess possible cytotoxicity, viability of cultured HaCat keratinocytes treated with K3AgBP or hypervalent silver oxynitrate was determined using an MTT assay. Treatment with 1 or 10 µM K3AgBP or Ag7NO11 for 2 or 24 h did not cause a significant reduction in cell viability. Signficanty, 10 µM K3AgBP augmented HaCat cell migration. Absence of cytotoxicity along with the unexpected effects on migration, as well as stability and antimicrobial and antibiofilm efficacy support the potential application of K3AgBP as a topical antimicrobial.

Association between Candida albicans and childhood dental caries in Japanese children

IntroductionThe possible association between Candida carriage in children and childhood caries has not been elucidated in the Japanese population. This study aimed to investigate the prevalence, maternal relatedness, and genotypic distribution of Candida albicans in this population. Materials and methodsWe collected dental plaque samples from 55 mother-child pairs in the Caries group and 25 pairs in the caries-free (CF) group to analyze microbial data (carriage and viable counts), focusing on Streptococcus mutans and C. albicans. Clinically isolated 118 Candida strains were further evaluated using arbitrarily primed polymerase chain reaction. ResultsA higher C. albicans carriage rate was observed in the Caries pairs (25.5 % in children, 47.3 % in mothers) than in CF pairs (0 % in children, 24.0 % in mothers). The viable counts of S. mutans were significantly higher in the Caries group than in the CF group (p < 0.05). In addition, S. mutans counts positively correlated with C. albicans counts in the dental plaque of caries-affected children (r = 0.549). Almost all Candida-positive children (92.9 %) were diagnosed with severe early childhood caries, and 79.7 % of Candida isolates from the mother-child pairs were similar at the strain level. C. albicans genotype A was the most predominant (70.6 %) strain, followed by genotype D (17.6 %) in dental plaques from children in the Caries group. ConclusionsThe presence of C. albicans is a risk factor for childhood caries in a Japanese population. Our findings provide new insights into maternal-child oral health instructions based on microbial factors associated with dental caries.

Pluronic F-127 Enhances the Antifungal Activity of Fluconazole against Resistant Candida Strains.

Candida strains as the most frequent causes of infections, along with their increased drug resistance, pose significant clinical and financial challenges to the healthcare system. Some polymeric excipients were reported to interfere with the multidrug resistance mechanism. Bearing in mind that there are a limited number of marketed products with fluconazole (FLU) for the topical route of administration, Pluronic F-127 (PLX)/FLU formulations were investigated in this work. The aims of this study were to investigate (i) whether PLX-based formulations can increase the susceptibility of resistant Candida strains to FLU, (ii) whether there is a correlation between block polymer concentration and the antifungal efficacy of the FLU-loaded PLX formulations, and (iii) what the potential mode of action of PLX assisting FLU is. The yeast growth inhibition upon incubation with PLX formulations loaded with FLU was statistically significant. The highest efficacy of the azole agent was observed in the presence of 5.0 and 10.0% w/v of PLX. The upregulation of the CDR1/CDR2 genes was detected in the investigated Candida strains, indicating that the efflux of the drug from the fungal cell was the main mechanism of the resistance.

Antimicrobial and Antioxidant Activity of Rhamnolipids Biosurfactant is Produced by Pseudomonas aeruginosa

Rhamnolipids are the glycolipid biosurfactant produced by different Pseudomonas species; they show antimicrobial activity and antioxidant. The findings of antimicrobial activity showed the rhamnolipid biosurfactant had an antimicrobial effect against the microorganisms at different concentrations, such as toward Bacillus cereus and Klebsiella pneumoniae, while a lower inhibitory effect toward Staphylococcus aureus and Pseudomonas aeruginosa. The rhamnolipid biosurfactant was shown to have a lower inhibitory effect against fungal strains Candida albicans and Aspergillus niger. The lower minimum inhibitory concentration (MIC) values of rhamnolipid biosurfactant toward the investigated microorganisms were 2 mg/ml for E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa and 3 mg/ml for Staphylococcus aureus, Enterobacter cloacae, Bacillus cereus, Proteus mirabilis, Candida albicans and Aspergillus niger. Rhamnolipid biosurfactant was tested as an antioxidant agent; the results showed 22.7 %, 47.4 %, 79.8 %, 85 % and 91.4 % of antioxidant activity at concentrations 5, 10. 15, 20 and 25 mg/ml, respectively. Cytotoxicity of the rhamnolipid biosurfactant was also examined at different concentrations against human erythrocytes. Hemolysis of the erythrocytes was observed at concentrations 100, 75, 50, 40 and 35 mg/ml, whereas the results exhibited no hemolysis at concentrations 25 and 15 mg/ ml. The study concluded that rhamnolipid biosurfactant showed effective antioxidant activity, no hemolysis at lower concentrations and has a high antimicrobial effect. The rhamnolipid biosurfactant is a suitable and great alternative to be employed as an effective and safe therapeutic agent. Keywords: Antimicrobial; Antioxidant; Cytotoxicity; Rhamnolipid; Pseudomonas aeruginosa