In vitro Azole Susceptibility Testing of Japanese Isolates of Itraconazole-Resistant Dermatophytes.

We conducted antifungal susceptibility testing on itraconazole (ITCZ)-resistant isolates of Trichophyton interdigitale and Trichophyton rubrum collected from Japanese patients in 2021 and 2022. The aim of the present study was to determine the most effective drug against ITCZ-resistant strains of dermatophytes. In all isolates, the minimum inhibitory concentrations (MICs) were > 32 mg/l for ITCZ, < 0.03 to 0.5 mg/l for ravuconazole (RVCZ), and < 0.03 mg/l for efinaconazole (EFCZ), luliconazole (LUCZ), and terbinafine (TRBF). Thus, in tinea unguium cases with ITCZ-resistant strains, treatment should be switched to TRBF or other azoles with a stronger antifungal efficacy, such as EFCZ, LUCZ, or RVCZ, and treatment must continue until the infectious organisms are completely eliminated.

Anti-dermatophytic activity of cold atmospheric plasma against Trichophyton rubrum via affecting fungal growth, morphology, drug susceptibility and HSP90 gene expression.

Trichophyton rubrum, a major human pathogenic dermatophyte, is responsible for the most recurrent dermatophytoses as globally important superficial fungal infections. Typical chemotherapy is used to handle such infections; however, emerging drug resistance and side effects necessitate the new remedial method development. Cold atmospheric plasma (CAP) is an emerging technology, consisted of neutral and charged particles and photons newly developed as a potent and safe antimicrobial technique to combat drug-resistant microbial pathogens. In the present study, the vast effects of CAP irradiation containing oxygen (2%) and helium (98%) on T. rubrum growth and pathogenicity were explored. After exposure of T. rubrum to CAP jet for 90, 120, 150, 180, and 210 s in 96-well microtiter plates, cell morphology and viability, ergosterol content of fungal hyphae, HSP90 gene expression, and the pattern of drug susceptibility were studied by using electron microscopy, RT-qPCR, spectrophotometry, disk diffusion and CLSI microbroth dilution methods. CAP irradiation significantly inhibited the fungal growth by 25.83 to 89.10%, reduced fungal cell viability by 11.68 to 87.71%, disrupted cellular membranous organelles and structures of the fungal hyphae, and suppressed efficiently the expression of HSP90 gene by 2 folds in 210 s exposure. Taken together, our results demonstrated that CAP is an efficient tool with potential in-vivo therapeutic applications against chronic dermatophytosis caused by T. rubrum due to its effectiveness, harmless, and ease of access.

Nannizzia incurvata in Hue city - Viet Nam: Molecular identification and antifungal susceptibility testing.

BACKGROUND: Nannizzia incurvata, a species belonging to the Nannizzia gypsea complex, is considered a neglected pathogen. OBJECTIVE: To detected N. incurvata isolates from dermatophytosis patients in Hue city - Viet Nam, and test the antifungal susceptibility of this species. Moreover, fungal capability to produce hydrolytic enzymes was evaluated. METHODS: Patients' samples were collected and cultured on Sabouraud-chloramphenicol-cycloheximide medium. Dermatophytes isolates were initially macroscopically and microscopically identified. ITS PCR-RFLP and ITS rDNA sequences were performed to determine and confirm species. An ITS Neighbor-Joining phylogenetic tree evaluated the genetic relationship among isolates. Fungal hydrolytic enzymes were examined, including lipase, phospholipase and protease. Antifungal susceptibility testing was carried out by the disk diffusion method. MICs of itraconazole, voriconazole, and terbinafine against these isolates were determined by the broth microdilution method. RESULTS: Twelve isolates of N. gypsea complex were preliminary morphologically identified. PCR-RFLP and ITS-rDNA sequencing identified and confirmed dermatophytes as N. incurvata strains, respectively. An evident polymorphism among isolates was highlighted in the phylogenetic tree. All isolates showed the activity of lipase, phospholipase, and protease production. Overall, all N. incurvata isolates were susceptible to itraconazole, voriconazole, clotrimazole, miconazole, and terbinafine. Few isolates were susceptible to griseofulvin, and none of them were susceptible to fluconazole. CONCLUSIONS: There was a presence of polyclonal N. incurvata isolates in dermatophytosis patients from Hue city, identified by PCR-RLFP and confirmed by ITS sequencing. We confirmed PCR-RLFP as a reliable technique to identify this species. Azole and terbinafine are the optimal choices for N. incurvata treatment except for fluconazole.

Characterization and Antidermatophyte Activity of Henna Extracts: A Promising Therapy for Humans and Animals Dermatophytoses.

Dermatophytoses representing a major global health problem and dermatophyte species with reduced susceptibility to antifungals are increasingly reported. Therefore, we investigated for the first time the antidermatophyte activity and phytochemical properties of the sequential extracts of the Egyptian privet Henna (Lawsonia inermis) leaves. Total phenolic content (TPC), total flavonoids (TF), and antioxidant activity of chloroform, diethyl ether, acetone, ethanol 80%, and aqueous extracts were evaluated. The antifungal activity of henna leaves extracts (HLE) toward 30 clinical dermatophytes isolates, including Trichophyton mentagrophytes, Microsporum canis, and T. rubrum, was determined. Morphological changes in hyphae were investigated using scanning electron microscopy (SEM) analysis. Following the polarity of ethanol and acetone, they exhibited distinct efficiency for the solubility and extraction of polyphenolic polar antioxidants from henna leaves. Fraxetin, lawsone, and luteolin-3-O-glucoside were the major phenolic compounds of henna leaves, as assessed using high-performance liquid chromatography analysis. A high and significant positive correlation was found between TPC, TF, the antioxidants, and the antidermatophyte activities of HLE. Acetone and ethanol extracts exhibited the highest antifungal activity toward the tested dermatophyte species with minimum inhibitory concentration (MIC) ranges 12.5-37.5 and 25-62.5 µg/mL, respectively. Structural changes including collapsing, distortion, inflating, crushing of hyphae with corrugation of walls, and depressions on hyphal surfaces were observed in SEM analysis for dermatophyte species treated with MICs of griseofulvin, acetone, and ethanol extracts. In conclusion, acetone and ethanolic extracts of henna leaves with their major constituent fraxetin exhibited effective antifungal activity toward dermatophyte species and may be developed as an alternative for dermatophytosis treatment. These findings impart a useful insight into the development of an effective and safe antifungal agent for the treatment of superficial fungal infections caused by dermatophytes.

In vitro activities of 8 antifungal agents against geophilic dermatophyte isolates.

BACKGROUND: Members of the Nannizzia gypsea complex are globally the most common geophilic dermatophytes which cause infection in animals and human. Although the susceptibility patterns of anthropophilic or zoophilic dermatophyte species to antifungal agents are well documented, the effectiveness of such drugs against geophilic species have rarely been explored. OBJECTIVES: This study was aimed to evaluate the in vitro antifungal activity of common and new antifungals against a set of environmental and clinical geophilic dermatophyte isolates. METHODS: 108 soil and clinical geophilic isolates from two genera Nannizzia (N. fulva n = 59; N. gypsea n = 43) and Arthroderma (A. quadrifidum n = 4; A. gertleri n = 1; A. tuberculatum n = 1) were included in the study. The in vitro antifungal susceptibility patterns of eight common and new antifungals against the isolates were determined according to broth microdilution method and by CLSI M38-A3 (3rd edition) protocol. RESULTS: MIC values across all isolates from five species ranged as: luliconazole: 0.0002-0.002 µg/ml, terbinafine: 0.008-0.125 µg/ml, efinaconazole: 0.008-0.125 µg/ml, ciclopirox olamine: 0.03-0.5 µg/ml, itraconazole: 0.125-1 µg/ml, amorolfine hydrochloride: 0.125-4 µg/ml, griseofulvin: 0.25-2 µg/ml and tavaborole: 1-8 µg/ml, respectively. CONCLUSION: Luliconazole, terbinafine and efinaconazole exhibited the highest in vitro efficacy, regardless of the dermatophyte species. Further surveillance studies are recommended to confirm the implication of such in vitro data for the clinical recovery rate of dermatophytosis with geophilic species following antifungal therapy.

Overall Prevalence and Prevalence Compared among Psoriasis Treatments of Onychomycosis in Patients with Nail Psoriasis and Fungal Involvement.

BACKGROUND: Whether nail psoriasis can increase the risk of onychomycosis is still being debated, and data relating to the prevalence of onychomycosis among psoriasis patients receiving different treatments is limited. OBJECTIVES: To investigate the overall prevalence and prevalence compared among psoriasis treatments of onychomycosis in patients with nail psoriasis and fungal involvement. METHODS: A prospective study of three groups of nail psoriasis being treated with only topical medication, methotrexate, or biologics (25 patients per group, 150 nails) was conducted at Siriraj Hospital (Bangkok, Thailand) during November 2018 to September 2020. Demographic data, psoriasis severity, and nail psoriasis severity were recorded. The nail most severely affected with psoriasis on each hand was selected for mycological testing. Potassium hydroxide, periodic acid-Schiff stain, and fungal culture were performed. RESULTS: The prevalence of onychomycosis in nail psoriasis was 35.3%. Among the treatment groups, the prevalence of onychomycosis was significantly higher in the methotrexate group than in the topical treatment and biologic treatment groups (p = 0.014). Candida spp. was the main causative organism, followed by Trichophyton rubrum. Thumb was most commonly affected (59.3%). The most common abnormality of the nail matrix and the nail bed was pitted nail (71.3%) and onycholysis (91.3%), respectively. Multivariate analysis revealed diabetes, wet-work exposure, and methotrexate treatment to be predictors of onychomycosis. CONCLUSIONS: Several factors, including psoriasis treatment, were shown to increase the risk of onychomycosis in nail psoriasis. Further research is needed to determine whether biologic agents, especially interleukin-17 inhibitors, can increase risk of onychomycosis and Candida infection/colonization of the nails.

Isolation, identification, and antimycotic activity of plumbagin from Plumbago europaea L. roots, leaves and stems.

Plumbago europaea L. is a plant utilized in Palestinian ethnomedicine for the treatment of various dermatological diseases. The current investigation was designed to isolate plumbagin from P. europaea leaves, roots and for the first time from the stems. Moreover, it aimed to evaluate the antimycotic activity against three human fungal pathogens causing dermatophytosis, also against an animal fungal pathogen. The qualitative analysis of plumbagin from the leaves, stems, and roots was conducted using HPLC and spectrophotometer techniques, while the structure of plumbagin was established utilizing Proton and Carbon-13 Nuclear Magnetic Resonance (NMR) and Infrared (IR) techniques. The entire plant constituents were determined by GC-MS. Moreover, the antimycotic activity against Ascosphaera apis, Microsporum canis, Trichophyton rubrum, and Trichophyton mentagrophytes was assessed utilizing the poison food technique method. The percentage of plumbagin recorded in the leaves, stems, and roots was found to be 0.51±0.001%, 0.16±0.001%, and 1.65±0.015%, respectively. The GC-MS examination declared the presence of 59 molecules in the plant extract. The plant extract and pure plumbagin exhibited complete inhibition against all tested dermatophytes at 6.0mg/mL for the extracts and 0.2mg/mL for plumbagin. P. europaea root is the best source of plumbagin and the plant extract could represent a potential drug candidate for the treatment of dermatophytosis infections. Further studies required to design suitable dosage forms from the natural P. europaea root extracts or plumbagin alone, to be utilized for the treatment of dermatological and veterinary ailments.

Machine Learning Data Augmentation as a Tool to Enhance Quantitative Composition-Activity Relationships of Complex Mixtures. A New Application to Dissect the Role of Main Chemical Components in Bioactive Essential Oils.

Scientific investigation on essential oils composition and the related biological profile are continuously growing. Nevertheless, only a few studies have been performed on the relationships between chemical composition and biological data. Herein, the investigation of 61 assayed essential oils is reported focusing on their inhibition activity against Microsporum spp. including development of machine learning models with the aim of highlining the possible chemical components mainly related to the inhibitory potency. The application of machine learning and deep learning techniques for predictive and descriptive purposes have been applied successfully to many fields. Quantitative composition-activity relationships machine learning-based models were developed for the 61 essential oils tested as Microsporum spp. growth modulators. The models were built with in-house python scripts implementing data augmentation with the purpose of having a smoother flow between essential oils' chemical compositions and biological data. High statistical coefficient values (Accuracy, Matthews correlation coefficient and F1 score) were obtained and model inspection permitted to detect possible specific roles related to some components of essential oils' constituents. Robust machine learning models are far more useful tools to reveal data augmentation in comparison with raw data derived models. To the best of the authors knowledge this is the first report using data augmentation to highlight the role of complex mixture components, in particular a first application of these data will be for the development of ingredients in the dermo-cosmetic field investigating microbial species considering the urge for the use of natural preserving and acting antimicrobial agents.

Real World Analysis of Response Rate and Efficacy of Oral Ketoconazole in Patients with Recalcitrant Tinea Corporis and Cruris.

Recalcitrant dermatophytosis has had an alarming rise in India with concomitant decreased effectiveness of conventional antifungal agents. This has prompted the use of second-line agents for treatment. In this retrospective study, we aimed to analyze the response rate, efficacy, relapse rate, and side effects of oral ketoconazole (KZ) in the treatment of recalcitrant tinea corporis and cruris. Institutional records were reviewed for patients presenting with tinea cruris or corporis who had failed treatment with conventional antifungal drugs and treated with oral KZ. Potassium hydroxide (KOH) findings, culture reports, and response to treatment was noted based on the percentage improvement in lesions and reduction in itching compared with baseline. Fourty-three patients (mean age 31.3 years) with tinea corporis/cruris who had taken prior treatment with antifungals were recruited in the study. KOH mount and culture were positive in 76.7% patients. Trichophyton mentagrophytes was the commonest species, isolated in 62.8% of patients. Ketoconazole showed the lowest minimum inhibitory concentration on antifungal susceptibility tests with various antifungals. With a dose of 400 mg daily, 67.4% of patients were cured of disease with mean duration of 9.4 weeks. Patients having less than 40% clearance at 2 weeks had a 68.9% less probability of getting cured of disease. Of the 29 patients cured, 37.9% relapsed because of various predisposing factors. Two patients developed increase in liver enzymes on treatment. Our analysis suggests that KZ can be used as alternative drug in cases with failure to conventional antifungal drugs. Though there are relapses, these can be partially explained by various predisposing factors that support fungal survival and transmission.

The Chemical Profiling of Essential Oils from Different Tissues of Cinnamomum camphora L. and Their Antimicrobial Activities.

Cinnamomum camphora L. is grown as an ornamental plant, used as raw material for furniture, as a source of camphor, and its essential oil can be used as an important source for perfume as well as alternative medicine. A comparative investigation of essential oil compositions and antimicrobial activities of different tissues of C. camphora was carried out. The essential oils were extracted by hydrodistillation with a Clevenger apparatus and their compositions were evaluated through gas chromatography-mass spectrometry (GC-MS), enantiomeric composition by chiral GC-MS, and antimicrobial properties were assayed by measuring minimum inhibitory concentrations (MICs). Different plant tissues had different extraction yields, with the leaf having the highest yield. GC-MS analysis revealed the presence of 18, 75, 87, 67, 67, and 74 compounds in leaf, branch, wood, root, leaf/branch, and leaf/branch/wood, respectively. The significance of combining tissues is to enable extraction of commercial quality essential oils without the need to separate them. The oxygenated monoterpene camphor was the major component in all tissues of C. camphora except for safrole in the root. With chiral GC-MS, the enantiomeric distributions of 12, 12, 13, 14, and 14 chiral compounds in branch, wood, root, leaf/branch, and leaf/branch/wood, respectively, were determined. The variation in composition and enantiomeric distribution in the different tissues of C. camphora may be attributed to the different defense requirements of these tissues. The wood essential oil showed effective antibacterial activity against Serratia marcescens with an MIC of 39.1 µg/mL. Similarly, the mixture of leaf/branch/wood essential oils displayed good antifungal activity against Aspergillus niger and Aspergillus fumigatus while the leaf essential oil was notably active against Trichophyton rubrum. C. camphora essential oils showed variable antimicrobial activities against dermal and pulmonary-borne microbes.

Modulation of ERG gene expression in fluconazole-resistant human and animal isolates of Trichophyton verrucosum.

Dermatophytes are a group of eukaryotic microorganisms characterized by high capacity to colonize keratinized structures such as the skin, hair, and nails. Over the past years, the incidence of infections caused by zoophilic species, e.g., Trichophyton verrucosum, has been increasing in some parts of the world, especially in Europe. Moreover, the emergence of recalcitrant dermatophytoses and in vitro resistant dermatophytes has become a cause of concern worldwide. Here, we analyzed the mechanisms underlying resistance to fluconazole among clinical isolates of T. verrucosum. Quantitative RT-PCR was carried out to determine the relative expression levels of mRNA transcripts of ERG3, ERG6, and ERG11 genes in the fungal samples using the housekeeping gene GAPDH as a reference. Our results showed that the upregulation of the ERG gene expression is a possible mechanism of resistance to fluconazole in this species. Furthermore, ERG11 is the most statistically significantly overexpressed gene in the pool of fluconazole-resistant T. verrucosum isolates. Additionally, we have demonstrated that exposure to fluconazole increases the levels of expression of ERG genes in fluconazole-resistant isolates of T. verrucosum. In conclusion, this study has shown one of the possible mechanisms of resistance to fluconazole among zoophilic dermatophytes, which involves the maintenance of high levels of expression of ERG genes after drug exposure.

Pharmacological validation of Solanum mammosum L. as an anti-infective agent: Role of solamargine.

ETHNOPHARMACOLOGICAL RELEVANCE: Fungal and bacterial infections remain a major problem worldwide, requiring the development of effective therapeutic strategies. Solanum mammosum L. (Solanaceae) ("teta de vaca") is used in traditional medicine in Peru to treat fungal infections and respiratory disorders via topical application. However, the mechanism of action remains unknown, particularly in light of its chemical composition. MATERIALS AND METHODS: The antifungal activity of TDV was determined against Trichophyton mentagrophytes and Candida albicans using bioautography-TLC-HRMS to rapidly identify the active compounds. Then, the minimum inhibitory concentration (MIC) of the fruit crude extract and the active compound was determined to precisely evaluate the antifungal activity. Additionally, the effects of the most active compound on the formation of Pseudomonas aeruginosa biofilms and pyocyanin production were evaluated. Finally, a LC-HRMS profile and a molecular network of TDV extract were created to characterize the metabolites in the fruits' ethanolic extract. RESULTS: Bioautography-TLC-HRMS followed by isolation and confirmation of the structure of the active compound by 1D and 2D NMR allowed the identification solamargine as the main compound responsible for the anti-Trichophyton mentagrophytes (MIC = 64 µg mL-1) and anti-Candida albicans (MIC = 64 µg mL-1) activities. In addition, solamargine led to a significant reduction of about 20% of the Pseudomonas aeruginosa biofilm formation. This effect was observed at a very low concentration (1.6 µg mL-1) and remained fairly consistent regardless of the concentration. In addition, solamargine reduced pyocyanin production by about 20% at concentrations of 12.5 and 50 µg mL-1. Furthermore, the LC-HRMS profiling of TDV allowed us to annotate seven known compounds that were analyzed through a molecular network. CONCLUSIONS: Solamargine has been shown to be the most active compound against T. mentoagrophytes and C. albicans in vitro. In addition, our data show that this compound affects significantly P. aeruginosa pyocyanin production and biofilm formation in our conditions. Altogether, these results might explain the traditional use of S. mammosum fruits to treat a variety of fungal infections and respiratory disorders.

Variability of the Chemical Composition and Bioactivity between the Essential Oils Isolated from Male and Female Specimens of Hedyosmum racemosum (Ruiz & Pav.) G. Don.

Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography-gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the principal constituent in male (28.24 and 25.90%) and female (26.47 and 23.90%) essential oil. Other main compounds were methyl chavicol, germacrene D, methyl eugenol, and α-pinene. Female essential oil presented a strong activity against Klebsiella pneumoniae (ATCC 9997) with an minimum inhibitory concentration (MIC) of 500 µg/mL and a scavenging capacity SC50 of 800 µg/mL.

Antifungal Activities of cis-trans Citral Isomers against Trichophyton rubrum with ERG6 as a Potential Target.

Trichophyton rubrum causes ringworm worldwide. Citral (CIT), extracted from Pectis plants, is a monoterpene and naturally composed of geometric isomers neral (cis-citral) and geranial (trans-citral). CIT has promising antifungal activities and ergosterol biosynthesis inhibition effects against several pathogenic fungi. However, no study has focused on neral and geranial against T. rubrum, which hinders the clinical application of CIT. This study aimed to compare antifungal activities of neral and geranial and preliminarily elucidate their ergosterol biosynthesis inhibition mechanism against T. rubrum. Herein, the disc diffusion assays, cellular leakage measurement, flow cytometry, SEM/TEM observation, sterol quantification, and sterol pattern change analyses were employed. The results showed geranial exhibited larger inhibition zones (p < 0.01 or 0.05), higher cellular leakage rates (p < 0.01), increased conidia with damaged membranes (p < 0.01) within 24 h, more distinct shriveled mycelium in SEM, prominent cellular material leakage, membrane damage, and morphological changes in TEM. Furthermore, geranial possessed more promising ergosterol biosynthesis inhibition effects than neral, and both induced the synthesis of 7-Dehydrodesmosterol and Cholesta-5,7,22,24-tetraen-3ß-ol, which represented marker sterols when ERG6 was affected. These results suggest geranial is more potent than neral against T. rubrum, and both inhibit ergosterol biosynthesis by affecting ERG6.

Antimicrobial and anthelmintic activities of the ethanolic extract, fractions and isolated compounds from Manilkara zapota L. P. Royen (Sapotaceae).

OBJECTIVES: To evaluate the antibacterial, antifungal and anthelmintic activities of the ethanolic extract (EEMz), fractions (LPFMz and HPFMz) and compounds isolated from the leaves of Manilkara zapota L. P. Royen. METHODS: Extract and fractions were produced by turbolization. LPFMz fraction was analysed by gas chromatography-mass spectrometry. The isolated compounds from HPFMz were purified by flash and preparative chromatographic methods, and chemically characterised by UPLC-ESITOFMS, optical rotation, and one- and two-dimensional 1H and 13C NMR techniques. Anthelmintic against Strongyloides venezuelensis and antimicrobial activities against Candida albicans, Trichophyton rubrum and Staphylococcus aureus were evaluated. KEY FINDINGS: EEMz showed mainly phenolic compounds and pentacyclic triterpenes from Δ12-oleane/Δ12-ursane series. Chlorogenic acid, myricetin-3-O-ß-D-glucopyranoside, mearnsitrin, germanicol and germanicol acetate were reported to M. zapota leaves for the first time in this work. EEMz, HPFMz, LPFMz showed significative activity against C. albicans (16 µg/mL), while isolated flavonoids were active against S. aureus (<32 µg/mL). EEMz, phenolic-rich compounds (F2), and chlorogenic acid were potentially active against S. venezuelensis at 24 h. CONCLUSIONS: M. zapota and its bioactive compound can be eligible such as a potential phytomedicine for the treatment of microbial and strongyloidiasis drug-resistant infections.

Antibacterial and Antifungal Polyketides from the Fungus Aspergillus unguis PSU-MF16.

Seven new polyketides including a phenol (1), two diphenyl ethers (2 and 3), two depsidones (4 and 5), and two phthalides (6 and 7) were isolated from the fungus Aspergillus unguis PSU-MF16 along with 27 known compounds. Their structures were determined by extensive spectroscopic analysis. The absolute configurations of 1 and 4-7 were established using comparative analyses of calculated and experimental ECD spectra. Among the new metabolites, 2 exhibited the best antimicrobial activity against Staphylococcus aureus, methicillin-resistant S. aureus, and Microsporum gypseum with equal MIC values of 16 µg/mL. In addition, known emeguisin A displayed potent antimicrobial activity against S. aureus, methicillin-resistant S. aureus, and Cryptococcus neoformans with equal MIC values of 0.5 µg/mL, compared with the standard drugs, vancomycin and amphotericin B. The structure-activity relationship study of the isolated compounds for antimicrobial activity is discussed.

Itraconazole resistance of Trichophyton rubrum mediated by the ABC transporter TruMDR2.

BACKGROUND: Dermatophytes showing reduced sensitivity to antifungal agents have emerged in several countries. One terbinafine resistant strain of Trichophyton rubrum, TIMM20092, also showed reduced sensitivity to itraconazole (ITC) and voriconazole (VRC). The expression of two genes (TruMDR2 and TruMDR3) encoding multidrug transporters of the ABC family was found to be highly up-regulated in this strain. Deletion of TruMDR3 in TIMM20092 abolished its resistance to VRC but only slightly reduced its resistance to ITC. OBJECTIVES: We examined the potential of T rubrum to develop resistance to ITC by analysing the mechanism of ITC resistance in TIMM20092. METHODS: The deletion of TruMDR2 by gene replacement was performed in TIMM20092 and one TruMDR3-lacking mutant (∆TruMDR3) previously generated from TIMM20092. TruMDR2 single and TruMDR2/TruMDR3 double mutants (∆TruMDR2 and ∆TruMDR2/3) were successfully obtained, respectively. RESULTS: The suppression of TruMDR2 was shown to abolish resistance to ITC in TIMM20092 and the TruMDR3-lacking mutant, strongly suggesting that TruMDR2 is a major contributor to ITC resistance in TIMM20092. CONCLUSIONS: Our study highlights the possible role of the ABC transporter TruMDR2 in ITC resistance of T. rubrum.

Antifungal Activity of New Diterpenoid Alkaloids Isolated by Different Chromatographic Methods from Delphinium peregrinum L. var. eriocarpum Boiss.

This paper aimed to investigate the potential antifungal influences of new alkaloids from Delphinium peregrinum L. var. eriocarpum Boiss. New Diterpenoid alkaloids Delcarpum (1), Hydrodavisine (4) and known alkaloids Peregrine (2), Delphitisine (3) were isolated by different chromatographic methods from the aerial parts of D. Peregrinum eriocarpum Boiss, which grows in Syria. The structures of alkaloids were proposed based on 1D NMR spectroscopy 1H-NMR, 13C-NMR, DEPT-135, DEPT-90, 2D NMR spectroscopy DQF-COSY, HMQC, EI-Ms mass spectrum, and IR spectroscopic measurements. The antifungal activity of the isolated alkaloids was evaluated against different dermatophyte fungal isolates compared with fluconazole. In the case of Peregrine (2) the minimum inhibitory concentrations(MICs) recorded 128-256, 32-64, and 32 for Epidermophyton floccosum, Microsporum canis, and Trichophyton rubrum, respectively, compared to 32-64, 16, and 32 µg/mL in the case of fluconazole, respectively. The MICs recorded on application of the four alkaloids mixture were 64, 32, and 16 in the case of E. floccosum, M. canis, and T. rubrum, respectively, which were significantly lower than that measured for each of the individual alkaloid and were compatible for fluconazole. In conclusion, MICs of the tested alkaloids showed a variable potential effect on the investigated fungal isolates. Peregrine (2) was the most effective alkaloid, however, the application of the mixture of alkaloids induced significant synergistic activity that was more pronounced than the application of individual ones.

Therapeutic efficacy of topically used luliconazole vs. terbinafine 1% creams.

OBJECTIVES: Dermatomycoses of zoophilic origin, especially those caused by Trichophyton mentagrophytes, often pose considerable therapeutic problems. This is reflected in the growing number of strains of this species with resistance to terbinafine caused by a mutation in the squalene epoxidase (SQLE) gene. Therefore, it is reasonable to look for alternative therapies to the commonly used terbinafine. The aim of the present study was to assess the in vivo effectiveness of topical therapy with luliconazole or terbinafine 1% cream. METHODS: Therapeutic efficacy was assessed using direct examination in KOH with DMSO, qPCR analysis with pan-dermatophyte primers and culturing. Moreover, in vitro susceptibility tests for luliconazole and terbinafine were performed. RESULTS: The results demonstrated significantly higher antifungal activity of luliconazole than terbinafine against dermatomycoses caused by T. mentagrophytes. The geometric mean of the MIC value for luliconazole against all T. mentagrophytes strains was 0.002 µg/ml, while this value for terbinafine was 0.004 µg/ml. In all studied cases, 28-day local therapy with luliconazole contributed to complete eradication of the aetiological agent of infection. CONCLUSIONS: Given the increasingly frequent reports of difficult-to-treat dermatophytoses caused by zoophilic terbinafine-resistant strains, the 1% luliconazole cream can be alternative solution in topical therapy.

In vitro antifungal susceptibility patterns of Trichophyton benhamiae complex isolates from diverse origin.

BACKGROUND: Species from the Trichophyton benhamiae complex are mostly zoophilic dermatophytes which cause inflammatory dermatophytosis in animals and humans worldwide. OBJECTIVES: This study was purposed to (a) to identify 169 reference and clinical dermatophyte strains from the T benhamiae complex species by molecular method and adhering to the newest taxonomy in the complex (b) to evaluate the in vitro antifungal susceptibility profile of these strains against eight common and new antifungal agents that may be used for the treatment of dermatophytosis. METHODS: All isolates, mainly originated from Europe but also from Iran, Japan and USA, were subjected to ITS-rDNA sequencing. The in vitro antifungal susceptibility profiles of eight common and new antifungal drugs against the isolates were determined by CLSI M38-A2 protocol and according to microdilution method. RESULTS: Based on the ITS-rDNA sequencing, T benhamiae was the dominant species (n = 102), followed by T europaeum (n = 29), T erinacei (n = 23), T japonicum (n = 10), Trichophyton sp (n = 4) and T eriotrephon (n = 1). MIC ranges across all isolates were as follows: luliconazole: 0.0002-0.002 µg/ml, terbinafine: 0.008-0.125 µg/ml, efinaconazole: 0.008-0.125 µg/ml, ciclopirox olamine: 0.03-0.5 µg/ml, itraconazole: 0.06-2 µg/ml, griseofulvin: 0.25-4 µg/ml, amorolfine hydrochloride: 0.125-4 µg/ml and tavaborole: 1-16 µg/ml. CONCLUSION: Luliconazole, efinaconazole and terbinafine were the most potent antifungals against T benhamiae complex isolates, regardless of the geographic locations where strains were isolated. These data might help dermatologists to develop effective therapies for successful treatment of infections due to T benhamiae complex species.