Carum copticum and Thymus vulgaris oils inhibit virulence in Trichophyton rubrum and Aspergillus spp

Emergence of drug-resistant strains has demanded for alternative means of combating fungal infections. Oils of Carum copticum and Thymus vulgaris have long been used in ethnomedicine for ailments of various fungal infections. Since their activity has not been reported in particular against drug-resistant fungi, this study was aimed to evaluate the effects of oils of C. copticum and T. vulgaris on the growth and virulence of drug-resistant strains of Aspergillus spp. and Trichophyton rubrum. The gas chromatography-mass spectrometry analysis revealed thymol constituting 44.71% and 22.82% of T. vulgaris and C. copticum, respectively. Inhibition of mycelial growth by essential oils was recorded in the order of thymol > T. vulgaris > C. copticum against the tested strains. RBC lysis assay showed no tested oils to be toxic even up to concentration two folds higher than their respective MFCs. Thymol exhibited highest synergy in combination with fluconazole against Aspergillus fumigatus MTCC2550 (FICI value 0.187) and T. rubrum IOA9 (0.156) as determined by checkerboard method. Thymol and T. vulgaris essential oil were equally effective against both the macro and arthroconidia growth (MIC 72 µg/mL). A > 80% reduction in elastase activity was recorded for A. fumigatus MTCC2550 by C. copticum, T. vulgaris oils and thymol. The effectiveness of these oils against arthroconidia and synergistic interaction of thymol and T. vulgaris with fluconazole can be exploited to potentiate the antifungal effects of fluconazole against drug-resistant strains of T. rubrum and Aspergillus spp.

Isolation of flavonoids from Anemopaegma arvense (Vell) Stellf. ex de Souza and their antifungal activity against Trichophyton rubrum

Anemopaegma arvense (Vell) Stellf. ex de Souza belongs to the family Bignoniaceae, and is popularly known as catuaba. To evaluate the cytotoxic and antimicrobial activity of A. arvense, fraction F3 and flavonoids 1 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside) (rutin) and flavonoid 2 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside) were isolated from the leaves of this plant. Fraction F3 and flavonoids 1 and 2 exhibited no antibacterial activity. Furthermore, no cytotoxic activity of fraction 3 or flavonoids 1 and 2 was observed against the tumor cells tested. However, analysis of the antifungal activity of flavonoids 1 and 2 revealed minimum inhibitory concentrations of 0.5 and 0.25 mg/mL, respectively, against the Trichophyton rubrum strains tested (wild type and mutant). This study demonstrates for the first time the antifungal activity of isolated flavonoids, validating the same activity for A. arvense.

Anemopaegma arvense pertence à família Bignoniaceae, sendo conhecida popularmente como Catuaba. Para avaliação de sua atividade citotóxica e antimicrobiana, a fração cromatográfica F3 e os flavonoides 1 (quercetina 3-O-α-L-ramnopiranosil-(1→6)-β-D-glucopiranosídeo) (rutina) e flavonoide 2 (quercetina 3-O-α-L-ramnopiranosil-(1→6)-β-D-galactopiranosídeo) foram isolados das folhas de A. arvense. A fração 3 e os flavonoides não apresentaram atividade antibacteriana. Nenhuma atividade citotóxica foi observada para a fração F3 e para os flavonoides, quando avaliados contra as células tumorais em teste. Entretanto, e considerando a atividade antifúngica, o flavonóide 1 apresentou valor de concentração inibitória mínima (CIM) de 0,5 mg/mL, enquanto o flavonóide 2, CIM de 0,25 mg/mL contra as cepas selvagem e mutante de Trichophyton rubrum, demonstrando, pela primeira vez, que os flavonoides isolados possuem atividade antifúngica, o que valida a mesma atividade para A. arvense.

Biological control of dermatophytic fungus Trichophyton species by Bacillus subtilis.

A potent Bacillus subtilis-2 isolated from soil samples, showed 14 mm inhibition zone by spot inoculation method and 22 mm inhibition zone by well agar diffusion method against pathogenic test fungii. i.e. Trichophyton species. Among four media tested, the maximum growth and antibiotic production was found in trypticase soya broth (TSB) medium at 37 degrees C, pH 7 and 48 hrs of incubation. The MIC of antifungal substance was 35 microl/ml. The isolated Bacillus subtilis -2 has strong antifungal activity against dermatophytic fungi Trichophyton sp. and requires chemical characterization for its bioactive principle.

Frequencia dos agentes etiologicos de onicomicose em pacientes hansenianos / ?

A anestesia de extremidades e uma caracteristica da hanseniase; os danos neural e vascular levam a deformidade. Uma das consequencias comuns e o comprometimento ungueal, apresentando-se principalmente sob a forma de distrofia, que pode ser colonizada por fungos. A infeccao micotica facilita o aparecimento de infeccoes bacterianas secundarias, que podem desencadear reacoes hansenicas, comprometendo a qualidade de vida do paciente. Neste trabalho, estudou-se a frequencia de agentes de onicomicose em 104 pacientes hansenianos com lesoes clinicamente compativeis. Foram utilizados exame micologico direto e cultura, que foi repetida por tes vezes. Encontrou-se frequencia de 91,3 por cento de onicomicose, com predominio de leveduras (60,0 por cento). Houve discordancia entre exame micologico direto e cultura em 27,6 por cento dos casos. Em 21,6 por cento dos exames diretos microscopicamente positivos nao foi observado crescimento fungico na respectiva cultura e em 6 por cento dos casos verificou-se exame micologico direto negativo e cultura positiva. Os dermatofitos represemtam 26, 7 por cento dos isolamentos, sendo Trichophyton rubrum o mais frequente (15, 3 por cento). Os fungos filamentosos nao dermatofitos foram 13,3 por cento das cepas isoladas, com maior frequencia do genero Scytalidium (10,5 por cento). Candida parapsilosis foi a especie de levedura mais frequente (21,53) por cento), seguida de C. tropicalis (7,69 por cento) e C. albicans (7,69 por cento). Os achados surgerm que as unhas destes pacientes sao suscetiveis as onicomicoses, principalmente com predisposicao a infeccao por agentes oportunistas...