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1.
BMC Microbiol ; 24(1): 196, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38849761

ABSTRACT

Biofilms produced by Candida albicans present a challenge in treatment with antifungal drug. Enhancing the sensitivity to fluconazole (FLC) is a reasonable method for treating FLC-resistant species. Moreover, several lines of evidence have demonstrated that berberine (BBR) can have antimicrobial effects. The aim of this study was to clarify the underlying mechanism of these effects. We conducted a comparative study of the inhibition of FLC-resistant strain growth by FLC treatment alone, BBR treatment alone, and the synergistic effect of combined FLC and BBR treatment. Twenty-four isolated strains showed distinct biofilm formation capabilities. The antifungal effect of combined FLC and BBR treatment in terms of the growth and biofilm formation of Candida albicans species was determined via checkerboard, time-kill, and fluorescence microscopy assays. The synergistic effect of BBR and FLC downregulated the expression of the efflux pump genes CDR1 and MDR, the hyphal gene HWP1, and the adhesion gene ALS3; however, the gene expression of the transcriptional repressor TUP1 was upregulated following treatment with this drug combination. Furthermore, the addition of BBR led to a marked reduction in cell surface hydrophobicity. To identify resistance-related genes and virulence factors through genome-wide sequencing analysis, we investigated the inhibition of related resistance gene expression by the combination of BBR and FLC, as well as the associated signaling pathways and metabolic pathways. The KEGG metabolic map showed that the metabolic genes in this strain are mainly involved in amino acid and carbon metabolism. The metabolic pathway map showed that several ergosterol (ERG) genes were involved in the synthesis of cell membrane sterols, which may be related to drug resistance. In this study, BBR + FLC combination treatment upregulated the expression of the ERG1, ERG3, ERG4, ERG5, ERG24, and ERG25 genes and downregulated the expression of the ERG6 and ERG9 genes compared with fluconazole treatment alone (p < 0.05).


Subject(s)
Antifungal Agents , Berberine , Biofilms , Candida albicans , Computational Biology , Drug Resistance, Fungal , Fluconazole , Microbial Sensitivity Tests , Berberine/pharmacology , Fluconazole/pharmacology , Candida albicans/drug effects , Candida albicans/genetics , Antifungal Agents/pharmacology , Drug Resistance, Fungal/genetics , Computational Biology/methods , Biofilms/drug effects , Biofilms/growth & development , Fungal Proteins/genetics , Fungal Proteins/metabolism , Drug Synergism , Gene Expression Regulation, Fungal/drug effects
2.
Food Microbiol ; 122: 104557, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38839221

ABSTRACT

To investigate the potential antifungal mechanisms of rhizosphere Actinobacteria against Ceratocystis fimbriata in sweet potato, a comprehensive approach combining biochemical analyses and multi-omics techniques was employed in this study. A total of 163 bacterial strains were isolated from the rhizosphere soil of sweet potato. Among them, strain MEPS155, identified as Streptomyces djakartensis, exhibited robust and consistent inhibition of C. fimbriata mycelial growth in in vitro dual culture assays, attributed to both cell-free supernatant and volatile organic compounds. Moreover, strain MEPS155 demonstrated diverse plant growth-promoting attributes, including the production of indole-3-acetic acid, 1-aminocyclopropane-1-carboxylate deaminase, phosphorus solubilization, nitrogen fixation, and enzymatic activities such as cellulase, chitinase, and protease. Notably, strain MEPS155 exhibited efficacy against various sweet potato pathogenic fungi. Following the inoculation of strain MEPS155, a significant reduction (P < 0.05) in malondialdehyde content was observed in sweet potato slices, indicating a potential protective effect. The whole genome of MEPS155 was characterized by a size of 8,030,375 bp, encompassing 7234 coding DNA sequences and 32 secondary metabolite biosynthetic gene clusters. Transcriptomic analysis revealed 1869 differentially expressed genes in the treated group that cultured with C. fimbriata, notably influencing pathways associated with porphyrin metabolism, fatty acid biosynthesis, and biosynthesis of type II polyketide products. These alterations in gene expression are hypothesized to be linked to the production of secondary metabolites contributing to the inhibition of C. fimbriata. Metabolomic analysis identified 1469 potential differently accumulated metabolites (PDAMs) when comparing MEPS155 and the control group. The up-regulated PDAMs were predominantly associated with the biosynthesis of various secondary metabolites, including vanillin, myristic acid, and protocatechuic acid, suggesting potential inhibitory effects on plant pathogenic fungi. Our study underscores the ability of strain S. djakartensis MEPS155 to inhibit C. fimbriata growth through the production of secretory enzymes or secondary metabolites. The findings contribute to a theoretical foundation for future investigations into the role of MEPS155 in postharvest black rot prevention in sweet potato.


Subject(s)
Ascomycota , Ipomoea batatas , Plant Diseases , Rhizosphere , Streptomyces , Ipomoea batatas/microbiology , Streptomyces/genetics , Streptomyces/metabolism , Streptomyces/isolation & purification , Plant Diseases/microbiology , Plant Diseases/prevention & control , Ascomycota/growth & development , Ascomycota/metabolism , Ascomycota/genetics , Soil Microbiology , Antifungal Agents/pharmacology , Antifungal Agents/metabolism , Multiomics
3.
Pak J Biol Sci ; 27(5): 256-267, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38840466

ABSTRACT

<b>Background and Objective:</b> The prioritisation of oil palm studies involves the exploration of novel bacterial isolates as possible agents for suppressing <i>Ganoderma boninense</i>. The objective of this study was to evaluate and characterise the potential of rhizospheric bacteria, obtained from the rhizosphere of oil palm plants, in terms of their ability to demonstrate anti-<i>Ganoderma </i>activity. <b>Materials and Methods:</b> The study began by employing a dual culture technique to select hostile bacteria. Qualitative detection was performed to assess the antifungal activity, as well as the synthesis of chitinase and glucanase, from certain isolates. The candidate strains were molecularly identified using 16S-rRNA ribosomal primers, specifically the 27F and 1492R primers. <b>Results:</b> The findings of the study indicated that the governmental plantation exhibited the highest ratio between diazotroph and indigenous bacterial populations in comparison to the other sites. Out of a pool of ninety bacterial isolates, a subset of twenty-one isolates demonstrated the ability to impede the development of <i>G. boninense</i>, as determined using a dual culture experiment. Twenty-one bacterial strains were found to exhibit antifungal activity. Nine possible bacteria were found based on the sequence analysis. These bacteria include <i>Burkholderia territorii</i> (RK2, RP2, RP3, RP5), <i>Burkholderia stagnalis</i> (RK3), <i>Burkholderia cenocepacia</i> (RP1), <i>Serratia marcescens</i> (RP13) and <i>Rhizobium multihospitium</i> (RU4). <b>Conclusion:</b> The findings of the study revealed that a significant proportion of the bacterial population exhibited the ability to perform nitrogen fixation, indole-3-acetic acid (IAA) production and phosphate solubilization. However, it is worth noting that <i>Rhizobium multihospitium</i> RU4 did not demonstrate the capacity for phosphate solubilization, while <i>B. territory</i> RK2 did not exhibit IAA production.


Subject(s)
Ganoderma , Rhizosphere , Ganoderma/metabolism , Ganoderma/growth & development , Biological Control Agents , Bioprospecting/methods , Soil Microbiology , Bacteria/metabolism , Bacteria/growth & development , Bacteria/genetics , Bacteria/isolation & purification , Arecaceae/microbiology , Plant Development , Palm Oil/metabolism , Antifungal Agents/metabolism , Antifungal Agents/pharmacology
4.
Med Mycol J ; 65(2): 33-38, 2024.
Article in English | MEDLINE | ID: mdl-38825528

ABSTRACT

Antifungal stewardship (AFS), compared with antimicrobial stewardship (AS), requires more advanced knowledge, skills, and multidisciplinary collaboration in its implementation. Therefore, fewer facilities are performing AFS compared with AS. At our hospital, we started AS and AFS in 2014. Our AFS programs include the following: i) interventions for patients with yeast-positive blood cultures, ii) introduction of a conditional antifungal notification system, and iii) commencement of AS team rounds. AFS for filamentous fungi includes bronchoscopy and microbial identification, including genetic and drug susceptibility testing. These AFS activities have improved several processes and outcome measures. However, our AFS team has faced several problems owing to the impact of COVID-19. This review introduces the practice of AFS, which we initiated at our hospital in 2014, and presents the current problems.


Subject(s)
Antifungal Agents , Antimicrobial Stewardship , Hospitals, University , Humans , Antifungal Agents/therapeutic use , Antifungal Agents/pharmacology , Antimicrobial Stewardship/methods , Japan , COVID-19 , SARS-CoV-2/drug effects , Mycoses/drug therapy
5.
Microb Cell Fact ; 23(1): 161, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38822407

ABSTRACT

Multi resistant fungi are on the rise, and our arsenal compounds are limited to few choices in the market such as polyenes, pyrimidine analogs, azoles, allylamines, and echinocandins. Although each of these drugs featured a unique mechanism, antifungal resistant strains did emerge and continued to arise against them worldwide. Moreover, the genetic variation between fungi and their host humans is small, which leads to significant challenges in new antifungal drug discovery. Endophytes are still an underexplored source of bioactive secondary metabolites. Many studies were conducted to isolate and screen endophytic pure compounds with efficacy against resistant yeasts and fungi; especially, Candida albicans, C. auris, Cryptococcus neoformans and Aspergillus fumigatus, which encouraged writing this review to critically analyze the chemical nature, potency, and fungal source of the isolated endophytic compounds as well as their novelty features and SAR when possible. Herein, we report a comprehensive list of around 320 assayed antifungal compounds against Candida albicans, C. auris, Cryptococcus neoformans and Aspergillus fumigatus in the period 1980-2024, the majority of which were isolated from fungi of orders Eurotiales and Hypocreales associated with terrestrial plants, probably due to the ease of laboratory cultivation of these strains. 46% of the reviewed compounds were active against C. albicans, 23% against C. neoformans, 29% against A. fumigatus and only 2% against C. auris. Coculturing was proved to be an effective technique to induce cryptic metabolites absent in other axenic cultures or host extract cultures, with Irperide as the most promising compounds MIC value 1 µg/mL. C. auris was susceptible to only persephacin and rubiginosin C. The latter showed potent inhibition against this recalcitrant strain in a non-fungicide way, which unveils the potential of fungal biofilm inhibition. Further development of culturing techniques and activation of silent metabolic pathways would be favorable to inspire the search for novel bioactive antifungals.


Subject(s)
Antifungal Agents , Endophytes , Antifungal Agents/pharmacology , Endophytes/metabolism , Humans , Microbial Sensitivity Tests , Cryptococcus neoformans/drug effects , Cryptococcus neoformans/metabolism , Fungi/drug effects , Fungi/metabolism , Aspergillus fumigatus/drug effects , Aspergillus fumigatus/metabolism , Candida albicans/drug effects
6.
Int J Nanomedicine ; 19: 4941-4956, 2024.
Article in English | MEDLINE | ID: mdl-38828194

ABSTRACT

Background: Due to its prevalence, recurrence, and the emergence of drug-resistance, Candida vaginitis significantly impacts the well-being of women. Although cinnamon essential oil (CEO) possesses antifungal activity, its hydrophobic properties limit its clinical application. Purpose: To overcome this challenge, a nanoemulsification technology was employed to prepare cinnamon essential oil-nanoemulsion (CEO@NE), and its therapeutic efficacy and action mechanism for Candida vaginitis was investigated in vivo and in vitro. Materials and Methods: CEO@NE, composed of 4% CEO, 78% distilled water, and 18% Tween 80, was prepared by ultrasonic nanoemulsification. The physical properties, anti-Candida activity, cytotoxicity, immunomodulatory potential and storage stability of CEO@NE were explored. Subsequently, the effect of intravaginal CEO@NE treatment on Candida vaginitis was investigated in mice. To comprehend the possible mechanism of CEO@NE, an analysis was conducted to ascertain the production of intracellular reactive oxygen species (ROS) in C. albicans. Results: CEO@NE, with the droplet size less than 100 nm and robust storage stability for up to 8 weeks, exhibited comparable anti-Candida activity with CEO. CEO@NE at the concentration lower than 400 µg/mL had no cytotoxic and immunomodulatory effects on murine splenocytes. Intravaginal treatment of CEO@NE (400 µg/mL, 20 µL/day/mouse for 5 consecutive days) curbed Candida colonization, ameliorated histopathological changes, and suppressed inflammatory cytokine production in mice intravaginally challenged with C. albicans. Notably, this treatment preserved the density of vaginal lactic acid bacteria (LAB) crucial for vaginal health. Co-culturing C. albicans with CEO@NE revealed concentration-dependent augmentation of intracellular ROS generation and ensuing cell death. In addition, co-culturing LPS-stimulated murine splenocytes with CEO@NE yielded a decrease in the generation of cytokines. Conclusion: This discovery provides insight into the conceivable antifungal and anti-inflammatory mechanisms of CEO@NE to tackle Candida vaginitis. CEO@NE offers a promising avenue to address the limitations of current treatments, providing novel strategy for treating Candida vaginitis.


Subject(s)
Antifungal Agents , Candida albicans , Candidiasis, Vulvovaginal , Cinnamomum zeylanicum , Emulsions , Oils, Volatile , Female , Animals , Oils, Volatile/chemistry , Oils, Volatile/pharmacology , Oils, Volatile/administration & dosage , Candidiasis, Vulvovaginal/drug therapy , Candida albicans/drug effects , Antifungal Agents/pharmacology , Antifungal Agents/chemistry , Antifungal Agents/administration & dosage , Mice , Administration, Intravaginal , Cinnamomum zeylanicum/chemistry , Emulsions/chemistry , Reactive Oxygen Species/metabolism , Humans , Nanoparticles/chemistry , Mice, Inbred BALB C
7.
Sci Rep ; 14(1): 12669, 2024 06 03.
Article in English | MEDLINE | ID: mdl-38830918

ABSTRACT

Dermatophytes show a wide geographic distribution and are the main causative agents of skin fungal infections in many regions of the world. Recently, their resistance to antifungal drugs has led to an obstacle to effective treatment. To address the lack of dermatophytosis data in Iraq, this study was designed to investigate the distribution and prevalence of dermatophytes in the human population and single point mutations in squalene epoxidase gene (SQLE) of terbinafine resistant isolates. The identification of 102 dermatophytes isolated from clinical human dermatophytosis was performed through morphological and microscopic characteristics followed by molecular analysis based on ITS and TEF-1α sequencing. Phylogeny was achieved through RAxML analysis. CLSI M38-A2 protocol was used to assess antifungal susceptibility of the isolates to four major antifungal drugs. Additionally, the presence of point mutations in SQLE gene, which are responsible for terbinafine resistance was investigated. Tinea corporis was the most prevalent clinical manifestation accounting for 37.24% of examined cases of dermatophytosis. Based on ITS, T. indotineae (50.98%), T. mentagrophytes (19.61%), and M. canis (29.41%) was identified as an etiologic species. T. indotineae and T. mentagrophytes strains were identified as T. interdigitale based on TEF-1α. Terbinafine showed the highest efficacy among the tested antifungal drugs. T. indotineae and T. mentagrophytes showed the highest resistance to antifungal drugs with MICs of 2-4 and 4 µg/mL, while M. canis was the most susceptible species. Three of T. indotineae isolates showed mutations in SQLE gene Phe397Leu substitution. A non-previously described point mutation, Phe311Leu was identified in T. indotineae and mutations Lys276Asn, Phe397Leu and Leu419Phe were diagnosed in T. mentagrophytes XVII. The results of mutation analysis showed that Phe397Leu was a destabilizing mutation; protein stability has decreased with variations in pH, and point mutations affected the interatomic interaction, resulting in bond disruption. These results could help to control the progression of disease effectively and make decisions regarding the selection of appropriate drugs for dermatophyte infections.


Subject(s)
Antifungal Agents , Arthrodermataceae , Drug Resistance, Fungal , Microbial Sensitivity Tests , Point Mutation , Squalene Monooxygenase , Tinea , Humans , Antifungal Agents/pharmacology , Iraq/epidemiology , Tinea/microbiology , Tinea/epidemiology , Tinea/drug therapy , Drug Resistance, Fungal/genetics , Male , Arthrodermataceae/genetics , Arthrodermataceae/drug effects , Arthrodermataceae/pathogenicity , Arthrodermataceae/isolation & purification , Female , Squalene Monooxygenase/genetics , Adult , Phylogeny , Terbinafine/pharmacology , Terbinafine/therapeutic use , Middle Aged , Adolescent , Young Adult , Child , Fungal Proteins/genetics , Aged
8.
Curr Microbiol ; 81(7): 213, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38847863

ABSTRACT

The antimalarial drug Mefloquine has demonstrated antifungal activity against growth and virulence factors of Candida albicans. The current study focused on the identification of Mefloquine's mode of action in C. albicans by performing cell susceptibility assay, biofilm assay, live and dead assay, propidium iodide uptake assay, ergosterol quantification assay, cell cycle study, and gene expression studies by RT-PCR. Mefloquine inhibited the virulence factors in C. albicans, such as germ tube formation and biofilm formation at 0.125 and 1 mg/ml, respectively. Mefloquine-treated cells showed a decrease in the quantity of ergosterol content of cell membrane in a concentration-dependent manner. Mefloquine (0.25 mg/ml) arrested C. albicans cells at the G2/M phase and S phase of the cell cycle thereby preventing the progression of the normal yeast cell cycle. ROS level was measured to find out oxidative stress in C. albicans in the presence of mefloquine. The study revealed that, mefloquine was found to enhance the ROS level and subsequently oxidative stress. Gene expression studies revealed that mefloquine treatment upregulates the expressions of SOD1, SOD2, and CAT1 genes in C. albicans. In vivo, the antifungal efficacy of mefloquine was confirmed in mice for systemic candidiasis and it was found that there was a decrease in the pathogenesis of C. albicans after the treatment of mefloquine in mice. In conclusion, mefloquine can be used as a repurposed drug as an alternative drug against Candidiasis.


Subject(s)
Antifungal Agents , Candida albicans , Candidiasis , Mefloquine , Virulence Factors , Antifungal Agents/pharmacology , Candida albicans/drug effects , Candida albicans/genetics , Candida albicans/pathogenicity , Candida albicans/growth & development , Animals , Mefloquine/pharmacology , Mice , Virulence Factors/genetics , Virulence Factors/metabolism , Candidiasis/microbiology , Candidiasis/drug therapy , Biofilms/drug effects , Biofilms/growth & development , Reactive Oxygen Species/metabolism , Microbial Sensitivity Tests , Oxidative Stress/drug effects , Cell Cycle/drug effects , Superoxide Dismutase-1/genetics , Superoxide Dismutase-1/metabolism , Ergosterol/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism
9.
Arch Microbiol ; 206(7): 290, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38847903

ABSTRACT

Clotrimazole is a type of antifungal medication developed from azole compounds. It exhibits several biological actions linked to oxidative stress. This study focuses on the oxidative effects of clotrimazole on the eukaryotic model yeast, Saccharomyces cerevisiae. Our results showed that although initial nitric oxide levels were above control in clotrimazole exposed cells, they showed decreasing tendencies from the beginning of incubation and dropped below control at 125 µM from the 60th min. The highest superoxide anion and hydrogen peroxide levels were 1.95- and 2.85-folds of controls at 125 µM after 15 and 60 min, respectively. Hydroxyl radical levels slightly increased throughout the incubation period in all concentrations and reached 1.3-fold of control, similarly at 110 and 125 µM in the 90th min. The highest level of reactive oxygen species was observed at 110 µM, 2.31-fold of control. Although NADH/NADPH oxidase activities showed similar tendencies for all conditions, the highest activities were found as 3.07- and 2.27-folds of control at 125 and 110 µM in the 15th and 30th min, respectively. The highest superoxide dismutase and catalase activities were 1.59- and 1.21-folds of controls at 110 µM clotrimazole in 30 and 90 min, respectively. While the drug generally induced glutathione-related enzyme activities, the ratios of glutathione to oxidized glutathione were above the control only at low concentrations of the drug. The levels of lipid peroxidation in all treated cells were significantly higher than the controls. The findings crucially demonstrate that this medicine can generate serious oxidative stress in organisms.


Subject(s)
Antifungal Agents , Catalase , Clotrimazole , Oxidative Stress , Saccharomyces cerevisiae , Superoxide Dismutase , Clotrimazole/pharmacology , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae/genetics , Antifungal Agents/pharmacology , Oxidative Stress/drug effects , Superoxide Dismutase/metabolism , Catalase/metabolism , Reactive Oxygen Species/metabolism , Hydrogen Peroxide/metabolism , Hydrogen Peroxide/pharmacology , Nitric Oxide/metabolism , Humans , Superoxides/metabolism , Oxidation-Reduction
11.
AAPS PharmSciTech ; 25(5): 130, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38844611

ABSTRACT

Naringenin (NRG) inhibits the fungal 17ß-hydroxysteroid dehydrogenase accountable for ergosterol synthesis in Candida albicans (C. albicans), a causative agent for cutaneous candidiasis. In present research, NRG was complexed with ZnO nanomaterial (NRG-Zn2+) to synthesize NRG-Zn2+ nanocomposites. The particle size and ζ-potential of NRG-Zn2+ nanocomposites were respectively estimated to be 180.33 ± 1.22-nm and - 3.92 ± 0.35-mV. In silico data predicted the greater affinity of NRG-Zn2+ nanocomposite for 14α-demethylase and ceramide in comparison to NRG alone. Later, NRG-Zn2+ nanocomposites solution was transformed in to naringenin-zinc oxide nanocomposites loaded chitosan gel (NRG-Zn-CS-Gel) with viscosity and firmness of 854806.7 ± 52386.43 cP and 698.27 ± 10.35 g, respectively. The ex-vivo skin permeation demonstrated 70.49 ± 5.22% skin retention, significantly greater (P < 0.05) than 44.48 ± 3.06% of naringenin loaded chitosan gel (NRG-CS-Gel) and 31.24 ± 3.28% of naringenin solution (NRG Solution). NRG-Zn-CS-Gel demonstrated 6.71 ± 0.84% permeation of NRG with a flux value of 0.046 ± 0.01-µg/cm2/h. The MIC50 of NRG-Zn-CS-Gel against C. albicans was estimated to be 0.156-µg/mL with FICI (fractional inhibitory concentration index) of 0.018 that consequently exhibited synergistic efficacy. Further, NRG-Zn-CS-Gel demonstrated superior antifungal efficacy in C. albicans induced cutaneous candidiasis infection in Balb/c mice. The fungal burden in NRG-Zn-CS-Gel treated group was 109 ± 25 CFU/mL, significantly lower (P < 0.05) than positive control (2260 ± 446 CFU/mL), naringenin loaded chitosan gel (NRG-CS-Gel; 928 ± 127 CFU/mL) and chitosan gel (CS-Gel; 2116 ± 186 CFU/mL) treated mice. Further, histopathology examination and cytokine profiling of TNF-α, IL-1ß and IL-10 revealed the healing of skin and inflammation associated with cutaneous candidiasis infection. In conclusion, NRG-Zn-CS-Gel may be a potential candidate for translating in to a clinical viable topical nanotherapeutic.


Subject(s)
Antifungal Agents , Candida albicans , Chitosan , Flavanones , Gels , Mice, Inbred BALB C , Nanocomposites , Zinc Oxide , Animals , Flavanones/administration & dosage , Flavanones/pharmacology , Mice , Candida albicans/drug effects , Chitosan/chemistry , Chitosan/administration & dosage , Nanocomposites/chemistry , Nanocomposites/administration & dosage , Antifungal Agents/administration & dosage , Antifungal Agents/pharmacology , Antifungal Agents/pharmacokinetics , Zinc Oxide/administration & dosage , Zinc Oxide/pharmacology , Zinc Oxide/chemistry , Drug Delivery Systems/methods , Skin/metabolism , Skin/drug effects , Skin/microbiology , Candidiasis/drug therapy , Polymers/chemistry , Skin Absorption/drug effects , Particle Size , Administration, Cutaneous
12.
Front Cell Infect Microbiol ; 14: 1375872, 2024.
Article in English | MEDLINE | ID: mdl-38846355

ABSTRACT

Introduction: Pseudomonas aeruginosa is notorious for its multidrug resistance and its involvement in hospital-acquired infections. In this study, 20 bacterial strains isolated from soil samples near the Hindan River in Ghaziabad, India, were investigated for their biochemical and morphological characteristics, with a focus on identifying strains with exceptional drug resistance and pyocyanin production. Methods: The isolated bacterial strains were subjected to biochemical and morphological analyses to characterize their properties, with a particular emphasis on exopolysaccharide production. Strain GZB16/CEES1, exhibiting remarkable drug resistance and pyocyanin production. Biochemical and molecular analyses, including sequencing of its 16S rRNA gene (accession number LN735036.1), plasmid-curing assays, and estimation of plasmid size, were conducted to elucidate its drug resistance mechanisms and further pyocynin based target the Candida albicans Strain GZB16/CEES1 demonstrated 100% resistance to various antibiotics used in the investigation, with plasmid-curing assays, suggesting plasmid-based resistance gene transmission. The plasmid in GZB16/CEES1 was estimated to be approximately 24 kb in size. The study focused on P. aeruginosa's pyocyanin production, revealing its association with anticandidal activity. The minimum inhibitory concentration (MIC) of the bacterial extract against Candida albicans was 50 µg/ml, with a slightly lower pyocyanin-based MIC of 38.5 µg/ml. Scanning electron microscopy illustrated direct interactions between P. aeruginosa strains and Candida albicans cells, leading to the destruction of the latter. Discussion: These findings underscore the potential of P. aeruginosa in understanding microbial interactions and developing strategies to combat fungal infections. The study highlights the importance of investigating bacterial-fungal interactions and the role of pyocyanin in antimicrobial activity. Further research in this area could lead to the development of novel therapeutic approaches for combating multidrug-resistant infections.


Subject(s)
Antifungal Agents , Candida albicans , Drug Resistance, Multiple, Bacterial , Microbial Sensitivity Tests , Plasmids , Pseudomonas aeruginosa , Pyocyanine , RNA, Ribosomal, 16S , Soil Microbiology , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/metabolism , Pyocyanine/metabolism , Drug Resistance, Multiple, Bacterial/genetics , Antifungal Agents/pharmacology , Candida albicans/drug effects , Candida albicans/genetics , Candida albicans/growth & development , RNA, Ribosomal, 16S/genetics , India , Plasmids/genetics , Anti-Bacterial Agents/pharmacology , Antibiosis
13.
BMC Microbiol ; 24(1): 200, 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38851702

ABSTRACT

There is an urgent need for new bioactive molecules with unique mechanisms of action and chemistry to address the issue of incorrect use of chemical fertilizers and pesticides, which hurts both the environment and the health of humans. In light of this, research was done for this work to isolate, identify, and evaluate the germination-promoting potential of various plant species' fungal endophytes. Zea mays L. (maize) seed germination was examined using spore suspension of 75 different endophytic strains that were identified. Three promising strains were identified through screening to possess the ability mentioned above. These strains Alternaria alternate, Aspergilus flavus, and Aspergillus terreus were isolated from the stem of Tecoma stans, Delonix regia, and Ricinus communis, respectively. The ability of the three endophytic fungal strains to produce siderophore and indole acetic acid (IAA) was also examined. Compared to both Aspergillus flavus as well as Aspergillus terreus, Alternaria alternata recorded the greatest rates of IAA, according to the data that was gathered. On CAS agar versus blue media, all three strains failed to produce siderophores. Moreover, the antioxidant and antifungal potentials of extracts from these fungi were tested against different plant pathogens. The obtained results indicated the antioxidant and antifungal activities of the three fungal strains. GC-Mass studies were carried out to determine the principal components in extracts of all three strains of fungi. The three strains' fungus extracts included both well-known and previously unidentified bioactive compounds. These results may aid in the development of novel plant growth promoters by suggesting three different fungal strains as sources of compounds that may improve seed germination. According to the study that has been given, as unexplored sources of bioactive compounds, fungal endophytes have great potential.


Subject(s)
Alternaria , Aspergillus , Bioprospecting , Endophytes , Germination , Seeds , Siderophores , Zea mays , Endophytes/metabolism , Endophytes/isolation & purification , Endophytes/physiology , Seeds/microbiology , Seeds/growth & development , Alternaria/growth & development , Alternaria/physiology , Zea mays/microbiology , Zea mays/growth & development , Aspergillus/metabolism , Aspergillus/growth & development , Siderophores/metabolism , Bioprospecting/methods , Indoleacetic Acids/metabolism , Antifungal Agents/pharmacology , Antifungal Agents/metabolism , Fungi/classification , Fungi/isolation & purification , Fungi/metabolism , Fungi/physiology , Antioxidants/metabolism , Aspergillus flavus/growth & development , Aspergillus flavus/metabolism
14.
Planta Med ; 90(7-08): 588-594, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38843798

ABSTRACT

Antimicrobial photodynamic therapy (aPDT) is an evolving treatment strategy against human pathogenic microbes such as the Candida species, including the emerging pathogen C. auris. Using a modified EUCAST protocol, the light-enhanced antifungal activity of the natural compound parietin was explored. The photoactivity was evaluated against three separate strains of five yeasts, and its molecular mode of action was analysed via several techniques, i.e., cellular uptake, reactive electrophilic species (RES), and singlet oxygen yield. Under experimental conditions (λ = 428 nm, H = 30 J/cm2, PI = 30 min), microbial growth was inhibited by more than 90% at parietin concentrations as low as c = 0.156 mg/L (0.55 µM) for C. tropicalis and Cryptococcus neoformans, c = 0.313 mg/L (1.10 µM) for C. auris, c = 0.625 mg/L (2.20 µM) for C. glabrata, and c = 1.250 mg/L (4.40 µM) for C. albicans. Mode-of-action analysis demonstrated fungicidal activity. Parietin targets the cell membrane and induces cell death via ROS-mediated lipid peroxidation after light irradiation. In summary, parietin exhibits light-enhanced fungicidal activity against all Candida species tested (including C. auris) and Cryptococcus neoformans, covering three of the four critical threats on the WHO's most recent fungal priority list.


Subject(s)
Antifungal Agents , Cryptococcus neoformans , Microbial Sensitivity Tests , Antifungal Agents/pharmacology , Cryptococcus neoformans/drug effects , Cryptococcus neoformans/radiation effects , Candida auris/drug effects , Light , Candida/drug effects , Reactive Oxygen Species/metabolism , Photochemotherapy/methods , Anthraquinones/pharmacology , Photosensitizing Agents/pharmacology
15.
Mycoses ; 67(5): e13728, 2024 May.
Article in English | MEDLINE | ID: mdl-38695201

ABSTRACT

BACKGROUND: Fungal keratitis is a severe eye infection that can result in blindness and visual impairment, particularly in developing countries. Fusarium spp. are the primary causative agents of this condition. Diagnosis of Fusarium keratitis (FK) is challenging, and delayed treatment can lead to serious complications. However, there is limited epidemiological data on FK, especially in tropical areas. OBJECTIVES: This study aimed to describe the clinical, laboratorial and epidemiological characteristics of FK in a tropical semi-arid region of Brazil. PATIENTS/METHODS: Adult patients with laboratory-confirmed FK diagnosed between October 2019 and March 2022 were evaluated. Fusarium isolates were characterized at molecular level and evaluated regarding antifungal susceptibility. RESULTS: A total of 226 clinical samples from patients suspected of keratitis were evaluated; fungal growth was detected in 50 samples (22.12%); out of which 42 were suggestive of Fusarium spp. (84%). Molecular analysis of a randomly selected set of 27 isolates identified F. solani species complex (n = 14); F. fujikuroi sensu lato (n = 6) and F. dimerum sensu lato (n = 7); a total of 10 haplotypes were identified among the strains. All but one Fusarium strains were inhibited by amphotericin B, natamycin and fluconazole. Most patients were male (71.42%; 30 out of 42), aged from 27 to 73 years old. Trauma was the most important risk factor for FK (40.47%; 17 out of 42). Patients were treated with antifungals, corticoids and antibiotics; keratoplasty and eye enucleation were also performed. CONCLUSIONS: The study provided insights into the characteristics of FK in tropical regions and emphasized the importance of enhanced surveillance and management strategies.


Subject(s)
Antifungal Agents , Eye Infections, Fungal , Fusariosis , Fusarium , Keratitis , Microbial Sensitivity Tests , Humans , Brazil/epidemiology , Fusarium/genetics , Fusarium/drug effects , Fusarium/isolation & purification , Fusarium/classification , Male , Female , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Adult , Keratitis/microbiology , Keratitis/epidemiology , Keratitis/drug therapy , Middle Aged , Fusariosis/microbiology , Fusariosis/epidemiology , Fusariosis/drug therapy , Eye Infections, Fungal/microbiology , Eye Infections, Fungal/epidemiology , Eye Infections, Fungal/drug therapy , Aged , Young Adult , Adolescent , Tropical Climate , Aged, 80 and over , Amphotericin B/pharmacology , Amphotericin B/therapeutic use
16.
Arch Microbiol ; 206(6): 251, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38727840

ABSTRACT

The prevalence of Candida albicans infection has increased during the past few years, which contributes to the need for new, effective treatments due to the increasing concerns regarding antifungal drug toxicity and multidrug resistance. Butyl isothiocyanate (butylITC) is a glucosinolate derivative, and has shown a significant antifungal effect contrary to Candida albicans. Additionally, how butylITC affects the virulence traits of C. albicans and molecular mode of actions are not well known. Present study shows that at 17.36 mM concentration butylITC inhibit planktonic growth. butylITC initially slowed the hyphal transition at 0.542 mM concentration. butylITC hampered biofilm development, and inhibits biofilm formation at 17.36 mM concentration which was analysed using metabolic assay (XTT assay) and Scanning Electron Microscopy (SEM). In addition, it was noted that butylITC inhibits ergosterol biosynthesis. The permeability of cell membranes was enhanced by butylITC treatment. Moreover, butylITC arrests cells at S-phase and induces intracellular Reactive Oxygen Species (ROS) accumulation in C. albicans. The results suggest that butylITC may have a dual mode of action, inhibit virulence factors and modulate cellular processes like inhibit ergosterol biosynthesis, cell cycle arrest, induces ROS production which leads to cell death in C. albicans.


Subject(s)
Antifungal Agents , Biofilms , Candida albicans , Cell Membrane , Isothiocyanates , Oxidative Stress , Reactive Oxygen Species , Candida albicans/drug effects , Candida albicans/physiology , Biofilms/drug effects , Antifungal Agents/pharmacology , Isothiocyanates/pharmacology , Oxidative Stress/drug effects , Cell Membrane/drug effects , Cell Membrane/metabolism , Reactive Oxygen Species/metabolism , Microbial Sensitivity Tests , Cell Cycle/drug effects , Hyphae/drug effects , Hyphae/growth & development , Ergosterol/metabolism
17.
Molecules ; 29(9)2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38731545

ABSTRACT

Functional Lyocell fibers gain interest in garments and technical textiles, especially when equipped with inherently bioactive features. In this study, Lyocell fibers are modified with an ion exchange resin and subsequently loaded with copper (Cu) ions. The modified Lyocell process enables high amounts of the resin additive (>10%) through intensive dispersion and subsequently, high uptake of 2.7% Cu throughout the whole cross-section of the fiber. Fixation by Na2CO3 increases the washing and dyeing resistance considerably. Cu content after dyeing compared to the original fiber value amounts to approx. 65% for reactive, 75% for direct, and 77% for HT dyeing, respectively. Even after 50 household washes, a recovery of 43% for reactive, 47% for direct and 26% for HT dyeing is proved. XRD measurements reveal ionic bonding of Cu fixation inside the cellulose/ion exchange resin composite. A combination of the fixation process with a change in Cu valence state by glucose/NaOH leads to the formation of Cu2O crystallites, which is proved by XRD. Cu fiber shows a strong antibacterial effect against Staphylococcus aureus and Klebsiella pneumonia bacteria, even after 50 household washing cycles of both >5 log CFU. In nonwoven blends with a share of only 6% Cu fiber, a strong antimicrobial (CFU > log 5) and full antiviral effectiveness (>log 4) was received even after 50 washing cycles. Time-dependent measurements already show strong antiviral behavior after 30 s. Further, the fibers show an increased die off of the fungal isolate Candida auris with CFU log 4.4, and nonwovens made from 6% Cu fiber share a CFU log of 1.7. Findings of the study predestines the fiber for advanced textile processing and applications in areas with high germ loads.


Subject(s)
Anti-Bacterial Agents , Antifungal Agents , Antiviral Agents , Copper , Antifungal Agents/pharmacology , Antifungal Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Copper/chemistry , Copper/pharmacology , Cellulose/chemistry , Cellulose/pharmacology , Staphylococcus aureus/drug effects , Textiles , Microbial Sensitivity Tests , Klebsiella pneumoniae/drug effects , Lignin/chemistry , Lignin/pharmacology , Humans
18.
Pak J Pharm Sci ; 37(2): 257-263, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38767092

ABSTRACT

The objective of this study was to identify the major compounds present in Cedar tar obtained by distillation of Cedrus atlantica wood from the Taza forest (Morocco) and to evaluate its antidermatophytic activity in vitro against the three strains of dermatophytes most widespread in Morocco, considered the main prevailing causes of fungal infections of the skin, hair and nails. GC/MS analysis revealed that cedar tar is composed mainly of hydrocarbon sesquiterpenes and oxygenated sesquiterpenes, with nine major compounds identified, including α-Cedrene, ß-Cadinene, γ-Cadinene, ß-Himachelene, α-Turmerone, ß-Turmerone, Ar-tumerone, α-Atlantone and Himachalol. The evaluation of antifungal activity was carried out by the micro dilution technique. The MIC values found were 100µg/mL, 2µg/mL and 0.1µg/mL on Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum canis strains respectively. The observed strong antifungal activity of cedar tar is attributed to the prevalence of oxygenated and hydrocarbon sesquiterpenes, known for their established antidermatophytic properties. This study highlights the potential of the Atlas Cedar tar as an effective antifungal agent for the treatment of superficial mycoses, particularly dermatophytoses.


Subject(s)
Antifungal Agents , Arthrodermataceae , Cedrus , Microbial Sensitivity Tests , Microsporum , Microsporum/drug effects , Antifungal Agents/pharmacology , Antifungal Agents/isolation & purification , Arthrodermataceae/drug effects , Cedrus/chemistry , Sesquiterpenes/pharmacology , Sesquiterpenes/isolation & purification , Plant Extracts/pharmacology , Plant Extracts/chemistry , Gas Chromatography-Mass Spectrometry , Phytochemicals/pharmacology , Phytochemicals/isolation & purification , Phytochemicals/analysis , Phytochemicals/chemistry , Morocco
19.
Nat Commun ; 15(1): 3770, 2024 May 04.
Article in English | MEDLINE | ID: mdl-38704366

ABSTRACT

Aspergillus fumigatus is the leading causative agent of life-threatening invasive aspergillosis in immunocompromised individuals. One antifungal class used to treat Aspergillus infections is the fungistatic echinocandins, semisynthetic drugs derived from naturally occurring fungal lipopeptides. By inhibiting beta-1,3-glucan synthesis, echinocandins cause both fungistatic stunting of hyphal growth and repeated fungicidal lysis of apical tip compartments. Here, we uncover an endogenous mechanism of echinocandin tolerance in A. fumigatus whereby the inducible oxylipin signal 5,8-diHODE confers protection against tip lysis via the transcription factor ZfpA. Treatment of A. fumigatus with echinocandins induces 5,8-diHODE synthesis by the fungal oxygenase PpoA in a ZfpA dependent manner resulting in a positive feedback loop. This protective 5,8-diHODE/ZfpA signaling relay is conserved among diverse isolates of A. fumigatus and in two other Aspergillus pathogens. Our findings reveal an oxylipin-directed growth program-possibly arisen through natural encounters with native echinocandin producing fungi-that enables echinocandin tolerance in pathogenic aspergilli.


Subject(s)
Antifungal Agents , Aspergillosis , Aspergillus fumigatus , Echinocandins , Fungal Proteins , Oxylipins , Antifungal Agents/pharmacology , Echinocandins/pharmacology , Aspergillus fumigatus/drug effects , Aspergillus fumigatus/metabolism , Fungal Proteins/metabolism , Fungal Proteins/genetics , Fungal Proteins/antagonists & inhibitors , Oxylipins/metabolism , Oxylipins/pharmacology , Aspergillosis/drug therapy , Aspergillosis/microbiology , Signal Transduction/drug effects , Gene Expression Regulation, Fungal/drug effects , Hyphae/drug effects , Hyphae/growth & development , Hyphae/metabolism , Transcription Factors/metabolism , Transcription Factors/genetics
20.
BMC Microbiol ; 24(1): 154, 2024 May 04.
Article in English | MEDLINE | ID: mdl-38704559

ABSTRACT

BACKGROUND: Side effects associated with antimicrobial drugs, as well as their high cost, have prompted a search for low-cost herbal medicinal substances with fewer side effects. These substances can be used as supplements to medicine or to strengthen their effects. The current study investigated the effect of oleuropein on the inhibition of fungal and bacterial biofilm in-vitro and at the molecular level. MATERIALS AND METHODS: In this experimental study, antimicrobial properties were evaluated using microbroth dilution method. The effect of oleuropein on the formation and eradication of biofilm was assessed on 96-well flat bottom microtiter plates and their effects were observed through scanning electron microscopy (SEM). Its effect on key genes (Hwp1, Als3, Epa1, Epa6, LuxS, Pfs) involved in biofilm formation was investigated using the quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) method. RESULTS: The minimum inhibitory concentration (MIC) and minimum fungicidal/bactericidal concentration (MFC/MBC) for oleuropein were found to be 65 mg/ml and 130 mg/ml, respectively. Oleuropein significantly inhibited biofilm formation at MIC/2 (32.5 mg/ml), MIC/4 (16.25 mg/ml), MIC/8 (8.125 mg/ml) and MIC/16 (4.062 mg/ml) (p < 0.0001). The anti-biofilm effect of oleuropein was confirmed by SEM. RT-qPCR indicated significant down regulation of expression genes involved in biofilm formation in Candida albicans (Hwp1, Als3) and Candida glabrata (Epa1, Epa6) as well as Escherichia coli (LuxS, Pfs) genes after culture with a MIC/2 of oleuropein (p < 0.0001). CONCLUSIONS: The results indicate that oleuropein has antifungal and antibacterial properties that enable it to inhibit or destroy the formation of fungal and bacterial biofilm.


Subject(s)
Antifungal Agents , Biofilms , Candida albicans , Candida glabrata , Escherichia coli , Fluconazole , Iridoid Glucosides , Iridoids , Microbial Sensitivity Tests , Biofilms/drug effects , Biofilms/growth & development , Iridoid Glucosides/pharmacology , Candida glabrata/drug effects , Candida glabrata/physiology , Candida glabrata/genetics , Candida albicans/drug effects , Candida albicans/genetics , Candida albicans/physiology , Escherichia coli/drug effects , Escherichia coli/genetics , Iridoids/pharmacology , Fluconazole/pharmacology , Antifungal Agents/pharmacology , Drug Resistance, Fungal , Anti-Bacterial Agents/pharmacology , Microscopy, Electron, Scanning
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