Antifungal Profile Research Articles

Antifungal, Antioxidant Activity, and GC-MS Profiling of Diaporthe amygdali GWS39: A First Report Endophyte from Geranium wallichianum.

Endophytic fungi serve as vital reservoirs of natural products. This study investigates the role of the endophytic fungus, Diaporthe amygdali GWS39, isolated from Geranium wallichianum D. Don Ex Sweet aerial stem. Showing a notable resemblance to Diaporthe amygdali, as confirmed through microscopic, molecular and phylogenetic techniques, this fungal endophyte displays promising antifungal and antioxidant capabilities. Remarkably, the present research marks the first report of D. amygdali as a stem inhabiting endophyte in an herbaceous perennial, Geranium wallichianum D. Don Ex Sweet on a global scale. This study pioneers the documentation of broad-spectrum antifungal activity exhibited by endophyte D. amygdali GWS39 against some economically important pathogens. The antioxidant activity of D. amygdali GWS39 crude extracts showed strong positive correlation, with R2 values of 0.99 for the methanolic extract and 0.93 for the ethyl acetate extract, indicating high antioxidant potential. In addition, the current investigation likely signifies the initial record of the bioactive chemical constituents of the endophyte D. amygdali GWS39 using GC-MS. In the GC-MS chromatogram of ethyl acetate extract, cyclohexaneamine, phenol, 2,6, dimethoxy-, benzenesulphonamide, N-(2,6, dimethylphenyl)-2-ethoxy-5-(tetrazol-1-yl), morpholine, 1-, beta, -d-Ribofuranosyl-3-[5-tetraazolyl]-1,2,4, triazole were identified. These compounds are previously reported for potent antibacterial, antifungal, antioxidant, antiviral, anticancer activities. The analysis of methanolic crude extract uncovers the presence of compounds such as arsenous acid tris(trimethylsilyl) ester, n-Hexadecanoic acid, methyl 10,11-octadecadienoate with noted antibiotic, antifungal, anti-inflammatory, antiviral, antihistaminic and anticancer activities.

Antifungal, antibacterial and DNA binding profile of three novel Zn(II), Cd(II) and Hg(II) complexes of a pyrazole-based Schiff-base ligand: Synthesis, crystal structures, DFT studies and spectroscopic investigation

Three new mononuclear Zn(II), Cd(II) and Hg(II) complexes, [Zn(MPAFA)3](ClO4)2 (1), [Cd(MPAFA)3](ClO4)2 (2) and [Hg(MPAFA)Cl2] (3) of a pyrazole based ‘NN’ bidentate Schiff-base ligand, N-(furan-2-ylmethyl)-1-(5-methyl-1H-pyrazol-3-yl)methanimine, (MPAFA) (L) were synthesized and characterized by elemental analyses, conductance, IR, NMR (1H and 13C), UV-Vis and fluorescence spectral techniques. Molar conductance measurements identified both 1 and 2 as 1:2 electrolytes, while 3 as a non-electrolyte. Single crystal X-ray diffraction studies recognized complexes 1 and 2 as distorted octahedral species with a N6 donor set. The presence of strong non-covalent interactions, such as intramolecular hydrogen bonding and π···π stacking within the complex molecules has been found to contribute to the enhanced stability of the complexes. In absence of single crystal, the structural feature of complex 3 has been confirmed by DFT studies and it has been found to adopt a distorted square-planar geometry with a N2Cl2 coordination. DFT calculations have also been conducted for 1 and 2. The TD-DFT absorption spectral studies supported the experimental results, indicating that the simulated peaks aligned reasonably well with the experimentally resolved peaks. Furthermore, the ligand and all its complexes exhibited effective antifungal activity against Colletotrichum siamense (AP1) and Fusarium equisetum (F.E) fungi. They also displayed promising antibacterial activity against both the gram-negative bacterium Klebsiella sp. (KS) and the gram-positive bacterium Methicillin-resistant Staphylococcus aureus (MRSA). The binding interactions of 1, 2 and 3 with calf-thymus DNA (CT-DNA) have also been studied using a combination of UV-Vis and fluorescence spectroscopic methods.

The mammalian Ire1 inhibitor, 4µ8C, exhibits broad anti-Aspergillus activity in vitro and in a treatment model of fungal keratitis.

The fungal unfolded protein response consists of a two-component relay in which the ER-bound sensor, IreA, splices and activates the mRNA of the transcription factor, HacA. Previously, we demonstrated that hacA is essential for Aspergillus fumigatus virulence in a murine model of fungal keratitis (FK), suggesting the pathway could serve as a therapeutic target. Here we investigate the antifungal properties of known inhibitors of the mammalian Ire1 protein both in vitro and in a treatment model of FK. The antifungal activity of Ire1 inhibitors was tested against conidia of several A. fumigatus isolates by a broth microdilution assay and against fungal biofilm by XTT reduction. The influence of 4μ8C on hacA mRNA splicing in A. fumigatus was assessed through gel electrophoresis and qRT-PCR of UPR regulatory genes. The toxicity and antifungal profile of 4μ8C in the cornea was assessed by applying drops to uninfected or A. fumigatus-infected corneas 3 times daily starting 4 hours post-inoculation. Corneas were evaluated daily through slit-lamp imaging and optical coherence tomography, or at endpoint through histology or fungal burden quantification via colony forming units. Among six Ire1 inhibitors screened, the endonuclease inhibitor 4μ8C displayed the strongest antifungal profile with an apparent fungicidal action. The compound both blocked conidial germination and hyphal metabolism of A. fumigatus Af293 in the same concentration range that blocked hacA splicing and UPR gene induction (60-120 µM). Topical treatment of sham-inoculated corneas with 0.5 and 2.5 mM 4μ8C did not impact corneal clarity, but did transiently inhibit epithelialization of corneal ulcers. Relative to vehicle-treated Af293-infected corneas, treatment with 0.5 and 2.5 mM drug resulted in a 50% and >90% reduction in fungal load, respectively, the latter of which corresponded to an absence of clinical signs of infection or corneal pathology. The in vitro data suggest that 4μ8C displays antifungal activity against A. fumigatus through the specific inhibition of IreA. Topical application of the compound to the murine cornea can furthermore block the establishment of infection, suggesting this class of drugs can be developed as novel antifungals that improve visual outcomes in FK patients.

Spectrum and Antifungal Drug Resistance among Fungal Pathogens Isolated from Prison Inmates in Nairobi, Kenya

Background The emergence of antifungal resistance in fungal pathogens highlights the need for local epidemiological data to guide empirical therapy in clinical settings. Fungal research and anti-fungal drug resistance studies are limited in developing countries; hence, there is a need for burden estimation in low- and middle-income countries. This study aimed to determine the spectrum of fungal pathogens and the anti-fungal resistance profile of fungal pathogens isolated from the respiratory and urinary tracts of prison inmates in Nairobi, Kenya. Methods A cross-sectional study was conducted in which sputum and urine samples were obtained from inmates presenting with symptoms of respiratory and urogenital infections at a prison outpatient clinic. One hundred and sixty-two samples were collected and subjected to fungal investigation using standard protocols. Susceptibility to fluconazole, itraconazole, and voriconazole was assessed using standard broth microdilution. Clinical and sociodemographic data were obtained using a structured questionnaire. Results From the 162, 94 samples were positive for fungal pathogens, with an overall prevalence of 58%. Seventeen (18%) of the isolated fungi were Aspergillus fumigatus, Aspergillus flavus and Histoplasma. There was a statistically significant difference between fungal pathogens isolated from the respiratory and urogenital tracts in both sexes (p<0.05). Antifungal susceptibility testing against itraconazole showed 2 of Aspergillus flavus and Aspergillus fumigatus were resistant. Conclusion Mycological agents are significant causes of respiratory and UTI infections among prison inmates, which could be attributed to prison conditions and misdiagnosis as bacterial infections. This highlights the need for specific control measures to reduce exposure to fungal infections in prisons and in the general population.

Antifungal susceptibility, molecular epidemiology, and clinical risk factors of Candida glabrata in intensive care unit in a Chinese Tertiary Hospital.

The increasing incidence and high mortality rate of Candida glabrata infection in ICU patients is an important issue. Therefore, it is imperative to investigate the antifungal susceptibility profiles and epidemiological characteristics in local regions. Herein, antifungal susceptibility testing was conducted to determine the minimum inhibitory concentrations (MICs) of eight antifungal drugs. Multilocus sequence typing (MLST) was used to study the strain genotype, geographical distribution, and susceptibility to antifungal agents among C. glabrata isolates. The mechanism of echinocandin resistance was explored by sequencing the FKS1 and FKS2 genes (encoding 1,3-β-D-glucan synthases) of echinocandin-resistant C. glabrata strains. Moreover, we further investigated the clinical manifestations and the various risk factors of patients infected with C. glabrata in the ICU. We selected 234 C. glabrata isolates from 234 patients in the ICU randomly for the follow-up study. Cross-resistance was found among the ICU C. glabrata isolates. Analysis using MLST showed that the genetic diversity among the C. glabrata isolates was low. Furthermore, sequence type showed no correlation with the antifungal resistance profiles, but was associated with geographical distribution. We also revealed novel mutations in FKS1 (S629P) and FKS2 (W1497stop) that mediated high-level echinocandin resistance (MIC >8 µg/mL). More than 14 days' stay in ICU (P=0.007), Acute Physiology and Chronic Health Evaluation II (APACHE-II) score (P=0.024), prior antifungal exposure (P=0.039) and lung disease (P=0.036) were significantly associated with antifungal resistant/non-wild-type C. glabrata infection. Our study shed light on the antifungal susceptibility, molecular epidemiology, and clinical risk factors of C. glabrata in the ICU of a Chinese Tertiary Hospital. Importantly, we revealed the molecular mechanism of echinocandin resistance. These results highlight the significance of continued surveillance in ICUs and provide data support for the treatment of C. glabrata in clinics.

Snakes as sentinel of zoonotic yeasts and bio-indicators of environmental quality.

Reptiles in the wild or as pets may act as spreaders of bacteria, viruses, fungi and parasites. However, studies on the mycobiota of these animals are scanty. This study investigates the occurrence of yeasts from the cloacal swabs of snakes of different origins and the antifungal profile of the isolated strains. A total of 180 cloacal samples of snakes were collected from Morocco (Group I: n = 68) and Italy (Group II: n = 112). Yeast species were biochemically and molecularly identified. A total of 72 yeast strains belonging to 13 genera, 8 from snakes in Group I and five from snakes in Group II were identified. The most frequently isolated species were Trichosporon asahii (22.2%) and Candida tropicalis (15.3%) from snakes in Group I and Debaryomyces spp. (16.7%) and Metahyphopichia silvanorum (11.1%) from snakes in Group II. Multiple azole and amphotericin B (AmB) resistance phenomena were detected among isolated yeasts. Azole multi drug resistance phenomena were detected among yeasts from Group I and Rhodotorula mucilaginosa from Group II, whereas AmB resistance phenomena among those from Group II. Data suggest that snakes may harbor pathogenetic yeasts, being potential reservoirs and spreaders of these organisms in the environment. Since the yeast species community from different groups of animals as well as their antifungal profile reflects the epidemiology of human yeast infections in the same geographical areas, the results indicate that snakes may be considered as sentinels for human/animal pathogenic microorganisms and bio-indicators of environmental quality.

Antifungal resistance profile and genetic relatedness of moulds from rural groundwater sources

Antifungal resistance remains a significant public health threat, yet poorly investigated. This study for the first time investigated the antifungal profile of moulds isolated from groundwaters in a rural community of Osun State, Southwest Nigeria. Groundwater samples were collected during dry and rainy seasons, and processed for mould isolation using standard methods. The isolates were presumptively identified and screened for in vitro susceptibility using 4 antifungals conventionally employed in clinical cases. Multiple antifungal resistance phenotypes and indices were equally evaluated. Representative of each putatively identified species were confirmed using molecular techniques. A total of 29 and 27 moulds were obtained during the dry and rainy seasons, respectively. Genus Aspergillus was the most prevalent (30.4%). Of the 56 isolates subjected to antifungal susceptibility testing, 55(98%) were resistant to fluconazole, followed by flucytosine 49(88%), ketoconazole 45(80%) and amphotericin B 31(55%). Exactly 46 isolates were multidrug-resistant, 23(50%) each, to 3 and 4 drugs, respectively. The multiple antifungal resistance index (MARI) evaluated was 1 in all the samples A-Q, except C (0.75), transcending the threshold limit of 0.2, indicating the isolates to be of high antifungal usage origin. The molecularly identified species had 99–100% similarity with reference strains from GenBank and evolutionary relationship of taxa revealed 10 distinct clades. The outcome of this study reveals a rise in the frequency of antifungal resistance in moulds towards standard drugs, thus, advocating for adequate investigations targeted at monitoring antifungal resistance in groundwater milieus.

Evaluating the Candida albicans and non-Albicans candida species isolated in different clinical samples and their in vitro antifungal susceptibity profile

Evaluating the Candida albicans and non-Albicans candida species isolated in different clinical samples and their in vitro antifungal susceptibity profile

Genotyping of oral Candida albicans and Candida tropicalis strains in patients with orofacial clefts undergoing surgical rehabilitation by MALDI-TOF MS: Case-series study

Patients with orofacial clefts are more likely to develop oral fungal diseases due to anatomo-physiological changes and surgical rehabilitation treatment. This case-series study evaluated the genetic diversity and dynamics of oral colonization and spread of C. albicans and C. tropicalis in four patients with orofacial clefts, from the time of hospital admission, perioperative and outpatient follow-up, with specialized physician. Candida biotypes previously identified by CHROMagar Candida and PCR methods were studied by MALDI-TOF MS assays and clustering analyses. Possible correlations with pathogenicity characteristics were observed, including production of hydrolytic exoenzymes and the antifungal sensitivity profiles. Amphotericin B-sensitive and fluconazole-resistant (low frequency) C. tropicalis and C. albicans, including clinically compatible MIC of nystatin, were found in the oral cavity of these patients. Clusters of isolates revealed phenomena of (i) elimination in the operative phase, (ii) maintenance or (iii) acquisition of oral C. tropicalis in the perioperative period and specialized outpatient and medical follow-up. For C. albicans, these phenomena included (i) elimination in the operative phase, (ii) acquisition in the operative phase and propagation from the hospital environment, and (iii) maintenance during hospitalization and operative phase. Amphotericin B and nystatin were shown to be effective in cases of clinical treatment and/or prophylaxis, especially considering the pre-existence of fluconazole-resistant strains. This study confirmed the phenomena of septic maintenance, septic neocolonization and septic elimination involving the opportunistic pathogens. MALDI-TOF MS associated with clustering analysis may assist the monitoring of clinical isolates or groups of epidemiologically important microbial strains in the hospital setting.

The mammalian Ire1 inhibitor, 4μ8C, exhibits broad anti-Aspergillus activity in vitro and in a treatment model of fungal keratitis.

The fungal unfolded protein response consists of a two-component relay in which the ER-bound sensor, IreA, splices and activates the mRNA of the transcription factor, HacA. Previously, we demonstrated that hacA is essential for Aspergillus fumigatus virulence in a murine model of fungal keratitis (FK), suggesting the pathway could serve as a therapeutic target. Here we investigate the antifungal properties of known inhibitors of the mammalian Ire1 protein both in vitro and in a treatment model of FK. The antifungal activity of Ire1 inhibitors was tested against conidia of several A. fumigatus isolates by a microbroth dilution assay and against fungal biofilm by XTT reduction. The influence of 4μ8C on hacA mRNA splicing in A. fumigatus was assessed through gel electrophoresis and qRT-PCR of UPR regulatory genes. The toxicity and antifungal profile of 4μ8C in the cornea was assessed by applying drops to uninfected or A. fumigatus-infected corneas 3 times daily starting 4 hours post-inoculation. Corneas were evaluated daily through slit-lamp imaging and optical coherence tomography, or at endpoint through histology or fungal burden quantification via colony forming units. Among six Ire1 inhibitors screened, the endonuclease inhibitor 4μ8C displayed the strongest antifungal profile with an apparent fungicidal action. The compound both blocked conidial germination and hyphal metabolism of A. fumigatus Af293 in the same concentration range that blocked hacA splicing and UPR gene induction (60-120 μM). Topical treatment of sham-inoculated corneas with 0.5 and 2.5 mM 4μ8C did not impact corneal clarity, but did transiently inhibit epithelialization of corneal ulcers. Relative to vehicle-treated Af293-infected corneas, treatment with 0.5 and 2.5 mM drug resulted in a 50% and >90% reduction in fungal load, respectively, the latter of which corresponded to an absence of clinical signs of infection or corneal pathology. The in vitro data suggest that 4μ8C displays antifungal activity against A. fumigatus through the specific inhibition of IreA. Topical application of the compound to the murine cornea can furthermore block the establishment of infection, suggesting this class of drugs can be developed as novel antifungals that improve visual outcomes in FK patients.

Exophiala species in household environments and their antifungal resistance profile

The black fungus Exophiala causes a wide range of infections from superficial to subcutaneous, but also invasive fungal infections in immunocompromised patients as well as healthy individuals. In addition, Exophiala, is a common colonizer of the air ways of patients with cystic fibrosis. However, the source of infection and mode of transmission is still unclear. The aim of this study was to investigate the presence of Exophiala in samples collected from Swedish indoor environments. We found that the Exophiala species were commonly found in dishwashers and that Exophiala dermatitidis was the most common Exophiala species, being identified in 70% (26 out of the 37) of samples. Almost all E. dermatitidis isolates had the ability to grow at 42 °C (P = 0.0002) and were catalase positive. Voriconazole and posaconazole exhibited the lowest MICs, while caspofungin and anidulafungin lack the antifungal activities in vitro. Future studies are needed to illuminate the transmission mode of the fungi.

Expanding the Structural Diversity of Tubulin-Targeting Agents: Development of Highly Potent Benzimidazoles for Treating Fungal Diseases.

Benzimidazoles, the representative pharmacophore of fungicides, have excellent antifungal potency, but their simple structure and single site of action have hindered their wider application in agriculture. In order to extend the structural diversity of tubulin-targeted benzimidazoles, novel benzimidazole derivatives were prepared by introducing the attractive pyrimidine pharmacophore. 2-((6-(4-(trifluoromethyl)phenoxy)pyrimidin-4-yl)thio)-1H-benzo[d]imidazole (A25) exhibited optimal antifungal activity against Sclerotinia sclerotiorum (S. s.), affording an excellent half-maximal effective concentration (EC50) of 0.158 μg/mL, which was higher than that of the reference agent carbendazim (EC50 = 0.594 μg/mL). Pot experiments revealed that compound A25 (200 μg/mL) had acceptable protective activity (84.7%) and curative activity (78.1%), which were comparable with that of carbendazim (protective activity: 90.8%; curative activity: 69.9%). Molecular docking displayed that multiple hydrogen bonds and π-π interactions could be formed between A25 and β-tubulin, resulting in a stronger bonding effect than carbendazim. Fluorescence imaging revealed that the structure of intracellular microtubules can be changed significantly after A25 treatment. Overall, these remarkable antifungal profiles of constructed novel benzimidazole derivatives could facilitate the application of novel microtubule-targeting agents.

Candida albicans in the oral cavities of pets: biofilm formation, putative virulence, antifungal resistance profiles and classification of the isolates.

The study aimed to investigate Candida albicans presence, antifungal resistance, biofilm formation, putative virulence genes, and molecular characterization in oral samples of dogs and cats. A total of 239 oral samples were collected from cats and dogs of various breeds and ages at Erciyes University, Faculty of Veterinary Medicine Clinics, between May 2017 and April 2018. Among 216 isolates obtained, 15 (6.95%) were identified as C. albicans, while 8 (3.7%) were non-albicans Candida species. Antifungal susceptibility testing revealed sensitivities to caspofungin, fluconazole, and flucytosine in varying proportions. Molecular analysis indicated the presence of fluconazole and caspofungin resistance genes in all C. albicans isolates. Additionally, virulence genes ALS1, HWP1, and HSP90 showed variable presence. Biofilm formation varied among isolates, with 46.7% strong, 33.3% moderate, and 20% weak producers. PCA analysis categorized isolates into two main clusters, with some dog isolates grouped separately. The findings underscore the significance of oral care and protective measures in pets due to C. albicans prevalence, biofilm formation, virulence factors, and antifungal resistance in their oral cavity, thereby aiding clinical diagnosis and treatment in veterinary medicine.

Functional Surfaces for Passive Fungal Proliferation Control: Effect of Surface Micro- and Nanotopography, Material, and Wetting Properties.

Fungal proliferation can lead to adverse effects for human health, due to the production of pathogenic and allergenic toxins and also through the creation of fungal biofilms on sensitive surfaces (i.e., medical equipment). On top of that, food spoilage from fungal activity is a major issue, with food losses exceeding 30% annually. In this study, the effect of the surface micro- and nanotopography, material (aluminum, Al, and poly(methyl methacrylate), PMMA), and wettability against Aspergillus awamori is investigated. The fungal activity is monitored using dynamic conditions by immersing the surfaces inside fungal spore-containing suspensions and measuring the fungal biomass growth, while the surfaces with the optimum antifungal properties are also evaluated by placing them near spore suspensions of A. awamori on agar plates. Al- and PMMA-based superhydrophobic surfaces demonstrate a passive-like antifungal profile, and the fungal growth is significantly reduced (1.6-2.2 times lower biomass). On the other hand, superhydrophilic PMMA surfaces enhance fungal proliferation, resulting in a 2.6 times higher fungal total dry weight. In addition, superhydrophobic surfaces of both materials exhibit antifouling and antiadhesive properties, whereas both superhydrophobic surfaces also create an "inhibition" zone against the growth of A. awamori when tested on agar plates.

Multidimensional Optimization of R-LE001 for New Leads with Enhanced Antifungal Profiles.

Scaffold hopping and structural fine-tuning are important strategies for agrochemical innovation. Multidimensional optimization of the prevalidated antifungal lead R-LE001 was conducted via the design, synthesis, and bioevaluation of 53 new compounds differing in either scaffold or substituent. The antifungal structure-activity relationship (SAR) revealed that a number of amides containing 2-(2-oxazolinyl) aniline (NHPhOx) or 2-(2-thiazolinyl) aniline (NHPhthiOx) demonstrated a more promising antifungal effect than both R-LE001 and the positive control boscalid. Specifically, compound 10 (encoded LEX-K01) shows an excellent antifungal effect against Botrytis cinerea with an EC50 value lower than 0.11 μM. This small change leads to a significant improvement (over 1 order of magnitude) in bioactivity compared to that of either R-LE001 (EC50 = 1.41 μM) or boscalid (EC50 = 2.01 μM) and fluxapyroxad (EC50 = 4.35 μM). With much lower resistance factors, LEX-K01 (10) was more efficacious against the two boscalid-resistant strains of B. cinerea TZ01 and NJBH2017. A combination of LEX-K01 (10) and boscalid in a ratio of 1:3 showed synergistic effects against resistant B. cinerea TZ01 and NJBH2017, with SR values of 3.01 and 2.55, respectively. LEX-K01 (10) has a curative efficacy (70.3%) more prominent than that of boscalid (51.2%) in controlling disease caused by B. cinerea. The molecular docking simulation of LEX-K01 (10) with the SDH protein of B. cinerea displayed four hydrogen bonds with amino acid residues TYR144, ARG88, TRP81, and SER84, rationalizing a stronger affinity than boscalid. The scanning electron microscopy (SEM) characteristic revealed that it could cause an obvious collapse of B. cinerea mycelium. This work indicates that LEX-K01 (10) has the potential to be further explored as a new antifungal agent.

Fusarioid keratitis and other superficial infections: A 10-years prospective study from Northeastern Brazil.

Fusarium and allied genera (fusarioid) species are common colonizers of roots and aerial plant parts, or act as phytopathogens in forestry and horticultural or grain crops. However, they can also cause a wide range of infections in humans, including onychomycosis, cutaneous and invasive infections. Fusarioid keratitis is characterized by an infection of the cornea with a suppurative and ulcerative appearance, which may cause damage to vision and permanent blindness. The aim of the present study was to investigate the prevalence of fusarioid species, biofilm formation and antifungal susceptibility profiling of clinical isolates recovered from patients with keratitis and dermatomycoses. The study was performed between March, 2012-December, 2022. Demographic, clinical and epidemiological data of patients were also collected. In the present study, most of the patients with keratitis were male (74%), had a median age of 42 years old, worked with plant material or debris and 26% of them reported eye trauma. Regarding dermatomycosis, most of patients were female and exhibited toenail lesions. Forty-seven isolates belonged to the genus Neocosmospora (78.33%), nine to the Fusarium fujikuroi (15%) and four to the Fusarium oxysporum (6.66%) species complexes. Several strains were moderate biofilm producers, specifically among Fusarium annulatum. Most strains showed increased MICs to amphotericin B and ketoconazole and low MICs to itraconazole. MICs ranged from 0.25 to 16 μg/mL for amphotericin B, 0.0625 to >16 μg/mL for ketoconazole and 0.125 to 8 for itraconazole. It is possible to conclude that fusarioid keratitis in Northeastern Brazil is an important and neglected disease, given the high number of cases, increased need for keratoplasty and poor outcome of the disease.

Current Perspectives of Antifungal Therapy: A Special Focus on Candida auris.

Candida auris is an emerging Candida sp. that has rapidly spread all over the world. The evidence regarding its origin and emerging resistance is still unclear. The severe infection caused by this species results in significant mortality and morbidity among the elderly and immunocompromised individuals. The development of drug resistance is the major factor associated with the therapeutic failure of existing antifungal agents. Previous studies have addressed the antifungal resistance profile and drug discovery for C. auris. However, complete coverage of this information in a single investigation is not yet available. In this review, we have mainly focused on recent developments in therapeutic strategies against C. auris. Based on the available information, several different approaches were discussed, including existing antifungal drugs, chemical compounds, essential oils, natural products, antifungal peptides, immunotherapy, antimicrobial photodynamic therapy, drug repurposing, and drug delivery systems. Among them, synthetic chemicals, natural products, and antifungal peptides are the prime contributors. However, a limited number of resources are available to prove the efficiency of these potential therapies in clinical usage. Therefore, we anticipate that the findings gathered in this review will encourage further in vivo studies and clinical trials.

Distribution and antifungal resistance profile of Candida spp. isolated from patients living with HIV at the Yaoundé Central Hospital

Distribution and antifungal resistance profile of Candida spp. isolated from patients living with HIV at the Yaoundé Central Hospital

Distribution and Antifungal Resistance Profile of <i>Candida</i> spp. Isolated from Patients Living with HIV at the Yaoundé Central Hospital

Background and Purpose: Candidiasis are the most frequent fungal infection, especially in immunocompromised people such as patients living with the human immunodeficiency virus (PLHIV). Data on the fungal prevalence and antifungal resistance rate particularly in PLHIV in Cameroon are scarce. This study aimed to determine the distribution and the antifungal resistance profile of<i> Candida </i>spp. isolated from clinical samples of PLHIV visiting the laboratory service of the Yaoundé Central Hospital. Materials and Methods: A cross-sectional study was carried out on the PLHIV visiting the Central Hospital of Yaoundé laboratory service. Samples were collected according to the signs and symptoms recorded by the patient and inoculated onto Sabouraud + Chloramphenicol agar medium for 24 hours incubation at 35°C ± 2°C. Typical <i>Candida</i> colonies were subjected to a germ tube test to identify <i>Candida albicans</i> and the other species were identified biochemically using API Candida (BioMérieux). The antifungal susceptibility testing was carried out by the disk diffusion method and seven antifungal discs (Bioanalyse) were tested. Results: Overall, 106 unique samples were obtained from participants. The positivity rate of <i>Candida </i>spp. was 37.7%. <i>Candida</i> isolates were mostly recovered from sputum (n=15/40) followed by the oral swabs (n=10/40) and the vaginal swabs (n=08/40). Out of the 40 isolates, <i>Candida albicans</i> was the predominant species 57.5% followed by <i>Candida krusei </i>15%, <i>Candida glabrata </i>and <i>Candida guilliermondii</i> 10% each and <i>Candida famata </i>7.5%. The antifungal drug resistance profile of <i>Candida</i> spp. revealed the highest resistance rates to Amphotericin B (95.0%), Fluconazole (57.5%) and Nystatin (42.5%). Conversely, Clotrimazole, Miconazole and Econazole were the most effective against <i>Candida</i> spp. Conclusion: The high frequency of <i>Candida </i>spp. isolation, resistant to several commonly used antifungals among PLHIV in a hospital setting is a direct call for stakeholders, policymakers and clinicians about antifungal therapy awareness in this vulnerable population.

In vitro inhibitory activity of Riparins against Candida spp. strains and in silico interaction with multi-drug-resistance proteins

Candida spp. includes opportunistic pathogens that are responsible for superficial and invasive infections. These strains have mechanisms of resistance against antimicrobials. Riparin compounds isolated from the green fruit of the plant Aniba riparia (Nees) Mez, are alkaloids with alkamide function with notable antimicrobial properties. We evaluated the inhibitory effect (in vitro) of Riparins isolated and combined with Fluconazole against strains of Candida albicans, C. tropicalis, and C. krusei; and in an in silico test, the anti-Candida activity of the factors MdR1, CdR1, and CdR2. Riparins were identified by 1D NMR spectroscopy (1 H and 13 C), electrospray ionization mass spectrometry (ESI-MS), and compared with previously reported spectral data. For the antifungal activity profile, the broth microdilution technique was used (1–1024 µg/mL). For combined antifungal activity, Riparins were tested at fixed subinhibitory concentrations (RI, RII, and RIV of 256 µg/mL and RIII, 64 µg/mL), and FCZ, ranging from 1 to 1024 µg/mL. Minimum Fungicide Concentration was performed by microculture in Petri dishes. For molecular docking, protein sequences were obtained from GenBank; targets were analyzed for homology, and model reliability was assessed using the Ramachandran plot. Composite stratification was performed by the MolDock Score, Rerank Score, PLANTS Score, and Vina Score. The results demonstrated that Riparins I, II, III, and IV, isolated or combined with FCZ have an inhibitory effect on Candida spp. cells, and a high probability of inhibiting antifungal resistance mechanisms, MdR1, CdR1, and CdR2.