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Vitro Antifungal Activity (vitro + antifungal_activity)
Selected AbstractsIn Vitro antifungal activity of extract and plumbagin from the stem bark of Diospyros crassiflora Hiern (Ebenaceae)PHYTOTHERAPY RESEARCH, Issue 7 2007J. P. Dzoyem Abstract In this study the methanol/dichloromethane (1:1) extract and plumbagin isolated from extract of stem barks of Diospyros crassiflora were tested for their antifungal activity against 12 strains of yeast pathogens and filamentous fungi: Candida albicans, Candida glabrata, Candida krusei, Candida tropicalis, Cryptococcus neoformans, Aspergillus niger, Aspergillus flavus, Alternaria sp., Cladosporium sp., Geotrichum candidum, Fusarium sp. and Penicillium sp. The growth of all fungi strains tested was inhibited by the extract and plumbagin. The diameter of inhibition zones varied from 12 to 18 mm and from 21 to 35 mm for the extract and plumbagin, respectively. The MIC values ranged from 12.5 to 25 mg/mL for the extract and 0.78,3.12 µg/mL for plumbagin. It is therefore suggested that extracts from the stem bark of Diospyros crassiflora could be used traditionally in the treatment of fungal infections. Compared with ketoconazole used as a standard antifungal, plumbagin could be considered as a promising antifungal agent. Copyright © 2007 John Wiley & Sons, Ltd. [source] Agar sublimation test for the in vitro determination of the antifungal activity of morpholine derivativesMYCOSES, Issue 5-6 2004A. Polak Antimykotische Aktivität; Morpholine; Sublimation Summary We studied the in vitro antifungal activities of a wide range of antimycotic agents, including amorolfine, terbinafine, naftifine, five morpholine derivatives, ciclopiroxolamine, bifonazole, clotrimazole, ketoconazole, itraconazole, fluconazole, voriconazole, flucytosine, amphotericin B, nystatin, and caspofungin, against Candida albicans and Trichophyton rubrum by conventional agar diffusion tests and by a novel sublimation method. For the sublimation method, 6 mm filter paper disks were soaked with defined amounts of antimycotic drugs, air dried, placed in the center of the lids of 9 cm Petri dishes, and incubated upside down with inoculated agar plates 10 mm above the disks. The conventional disk diffusion tests produced inhibition zones as previously described. The disk sublimation tests produced large inhibition zones with amorolfine, five amorolfine derivatives, and terbinafine, but with none of the other antifungal agents. Possible therapeutic advantages of agents, which are able to overcome air cavities in mycotic lesions, e.g. in onychomycosis, are discussed. Zusammenfassung Wir untersuchten in vitro die antimykotische Aktivität eines breiten Spektrums von Antimykotika, einschließlich Amorolfin, Terbinafin, Naftifin, fünf Morpholin-Derivaten, Ciclopiroxolamin, Bifonazol, Clotrimazol, Ketoconazol, Itraconazol, Fluconazol, Voriconazol, 5-Fluorcytosin, Amphotericin B, Nystatin und Caspofungin, gegenüber Candida albicans und Trichophyton rubrum mit konventionellen Agardiffusionstesten und mit einer neuartigen Sublimationsmethode. Für die Sublimationsmethode wurden 6 mm-Filterpapier-Blättchen mit definierten Mengen von Antimykotika getränkt, luftgetrocknet, in die Mitte der Deckel von 9 cm-Petrischalen gelegt und mit der inokulierten Agarplatte 10 mm über den Blättchen umgedreht inkubiert. Die konventionellen Agardiffusionsteste produzierten Hemmhöfe wie früher beschrieben. Die Blättchen-Sublimationsteste produzierten große Hemmhöfe mit Amorolfin, fünf Morpholin-Derivaten und Terbinafin, nicht jedoch mit den anderen Antimykotika. Mögliche therapeutische Vorteile von Agentien, die luftgefüllte Hohlräume in mykotischen Läsionen überbrücken können, z. B. im Nagel bei Onychomykose, werden diskutiert. [source] Herbal medicines for treatment of fungal infections: a systematic review of controlled clinical trialsMYCOSES, Issue 3-4 2004Karen W. Martin Antimykotische Chemotherapie; Phytomedizin Summary Traditional medicine has made use of many different plant extracts for treatment of fungal infections and some of these have been tested for in vitro antifungal activity. This systematic review evaluates antifungal herbal preparations that have been tested in controlled clinical trials. Four electronic databases were searched for controlled clinical trials of antifungal herbal medicines. Data were extracted in a standardized manner by two independent reviewers and are reviewed narratively. Seven clinical trials met our inclusion criteria. Tea tree oil preparations were tested in four randomized clinical trials and some positive outcomes were attributed to the intervention in all trials. Solanum species (two trials) and oil of bitter orange preparations (one trial) were compared with conventional treatments. In all cases encouraging results were reported. There are few controlled clinical trials of herbal antifungal medicines. The most thoroughly clinically tested is tea tree oil, which holds some promise. All herbal remedies require further investigation in rigorous clinical trials. Zusammenfassung Die traditionelle Medizin nutzt eine Vielzahl unterschiedlicher Pflanzenextrakte zur Behandlung von Pilzinfektionen, die teilweise auf antimyzetische Wirksamkeit in vitro untersucht wurden. Dieser Überblick bewertet diejenigen antimyzetischen Zubereitungen pflanzlichen Ursprungs, die in kontrollierten klinischen Studien geprüft worden sind. Zu diesem Zweck wurden vier elektronische Datenbanken gesichtet. Die Daten wurden mit einer standardisierten Methode von zwei unabhängigen Gutachtern erhoben und werden im Folgenden bewertend dargestellt. Sieben klinische Studien erfüllten unsere Einschlusskriterien. Teebaumöl-Zubereitungen wurden in vier randomisierten klinischen Studien getestet, und einige positive Ergebnisse wurden in allen Studien auf den Wirkstoff zurückgeführt. Zubereitungen von Solanum -Arten (zwei Studien) und Orangenbitteröl wurden mit konventionellen Behandlungsmethoden verglichen. In allen Studien wurden ermutigende Resultate erzielt. Diese wenigen kontrollierten klinischen Studien mit antimyzetischen Zubereitungen pflanzlichen Ursprungs ergaben, dass Teebaumöl am vielversprechendsten ist. Alle pflanzlichen Zubereitungen erfordern jedoch weitere Studien unter kritischen klinischen Versuchbedingungen. [source] In vitro antifungal activity of brassinin, camalexin and two isothiocyanates against the crucifer pathogens Alternaria brassicicola and Alternaria brassicaePLANT PATHOLOGY, Issue 2 2007A. Sellam In vitro assays investigated the responses of Alternaria brassicicola and A. brassicae isolates towards two crucifer phytoalexins and two isothiocyanates (ITC) by evaluating their potential toxic effects on different fungal growth parameters. Although variable responses towards each compound was observed within the species A. brassicicola, the results obtained confirmed the antifungal effects of camalexin, brassinin, allyl- (AlITC) and benzyl- (BzITC) isothiocyanates, at different developmental stages of both Alternaria species. Irrespective of the tested isolate, the phytoalexin camalexin exhibited the greater inhibitory effect with mean EC50 values ranging from 34 µm (germ-tube elongation) to 183 µm (mycelial growth). Germ-tube elongation was more sensitive compared to conidial germination and mycelial growth, with mean EC50 values of the former of 81 µm, 520 µm and 870 µm for brassinin, BzITC and AlITC, respectively. [source] Enantioselectivity of inhibition of cytochrome P450 3A4 (CYP3A4) by ketoconazole: Testosterone and methadone as substratesCHIRALITY, Issue 2 2004Shahrzad Dilmaghanian Abstract Racemic ketoconazole (KTZ) was the first orally active azole antifungal agent used in clinical practice and has become widely used in the treatment of mucosal fungal infections associated with AIDS immunosuppression and cancer chemotherapy. However, the use of KTZ has been limited because of adverse drug,drug interactions. KTZ blocks ergosterol biosynthesis by inhibiting the fungal cytochrome P450 (CYP51). KTZ is also a potent inhibitor of human cytochrome P450 3A4 (CYP3A4) enzyme, the major drug-metabolizing CYP isozyme in the human liver. We examined the enantioselective differences of KTZ in the inhibition of human CYP3A4 and in antifungal action. Dextro - and levo -KTZ exhibited modest enantioselective differences with respect to CYP3A4 inhibition of testosterone and methadone metabolism. For both substrates levo -KTZ was approximately a 2-fold more potent inhibitor. We examined the enantioselective differences in the in vitro activity of KTZ against medically relevant species of Candida and Aspergillus, as well as Cryptococcus neoformans. Overall, levo -KTZ was 2,4-fold more active than dextro -KTZ. Therefore, levo -KTZ is a more potent inhibitor of CYP3A4 and has stronger in vitro antifungal activity. Chirality 16:79,85, 2004. © 2004 Wiley-Liss, Inc. [source] In vitro antifungal susceptibility patterns of dermatophyte strains causing tinea unguiumCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 6 2007E. Sarifakioglu Summary Background., Dermatophytes are the major responsible organisms in onychomycosis. Although recent antifungal agents have high success rates in treating this condition, lack of clinical response may occur in 20%. Antifungal drug resistance may be one of the causes of treatment failure. The need for in vitro antifungal drug resistance in daily practice is still under discussion. Objective., We aimed to determine the in vitro susceptibility patterns of dermatophytes causing onychomycosis, against the traditionally available systemic antifungal agents terbinafine, itraconazole and fluconazole. Methods., In total, 100 otherwise healthy patients with suspected onychomycosis were included. Nail clippings were cultured on Sabouraud dexrose agar, mycobiotic agar and dermatophyte test medium. Antifungal susceptibility tests were carried out, mainly following The National Committee for Clinical and Laboratory Standards (M38-P) protocol standard for filamentous fungi. Different concentrations of terbinafine (0.008,8 µg/mL), itraconazole (0.015,16 µg/mL) and fluconazole (0.06,64 µg/mL) were tested. Minimum inhibitory concentration end-point determination was chosen as 100% growth inhibition for terbinafine and 80% for azoles. Results., Of the 100 nail samples, 43% grew dermatophytes. The main causative organism was Trichophyton rubrum (91%) followed by Trichophyton mentagrophytes (9%). Terbinafine had the lowest minimum inhibitory concentration (0.008 µg/mL) followed by itraconazole. Fluconazole showed the greatest variation in minimum inhibitory concentration (0.03,2 µg/mL) and had different susceptibility patterns for the two species. Conclusions., Of the three antifungals tested, terbinafine had the most potent in vitro antifungal activity against dermatophytes. Antifungal susceptibility tests would be useful to screen antifungal-resistant dermatophyte strains. [source] Clinical and microbiological assessment of patients with a long-term diagnosis of human immunodeficiency virus infection and Candida oral colonizationCLINICAL MICROBIOLOGY AND INFECTION, Issue 4 2009A. C. D. Delgado Abstract The objective of this study was to evaluate Candida oral colonization in human immunodeficiency virus (HIV)-infected patients undergoing long-term highly active antiretroviral therapy (ARV). The cross-sectional study included 331 HIV patients, diagnosed from 1983 to 2003. Oral swabs were performed, and Candida species were determined using ID 32C. Isolates were tested for antifungal susceptibility. Clinical and laboratory data were collected to identify the association with Candida colonization. In total, 161 Candida isolates were detected among 147 of the 331 patients (44%), independently of the time when HIV infection was diagnosed. Candida albicans strains represented 137 (85%) of the isolates, and were susceptible to all of the tested antifungal drugs. Among the non- C. albicans strains, six isolates were dose-dependently susceptible to fluconazole, nine to itraconazole, and seven to ketoconazole. The isolation of Candida was significantly higher in patients with virological failure (83/147; p 0.0002) and CD4+ T-lymphocyte counts <200 cells/mm3 (30/83; p 0.0003). Recovery of Candida in the oral cavity was independent of protease inhibitor (PI) usage (p 0.60). Colonized patients typically underwent salvage therapy (p 0.003), and had more episodes of opportunistic fungal infections (p 0.046) and malignancies (p 0.004). Oral Candida colonization in patients under ARV therapy was associated with the immunosupressed status of HIV-infected patients, i.e. low number of CD4+ T-cells per cubic millimetre, failure of ARV therapy (salvage therapy), and higher number of opportunistic infections and malignancies. Despite the fact that PIs have in vitro antifungal activity, the use of this class of antiretroviral agent did not influence the presence of Candida in the oral cavity of AIDS patients. [source] | ||||||||||