Antifungal activity of Croton macrostachyus Leaf and Bark crude Extract against Trichophyton rubrum

<strong>Abstract</strong>: Dermatophytes are fungal pathogens of humans and animals infecting the keratinized tissues mainly skin, nails and hairs. Among dermatophytes, Trichophyton rubrum is the most common etiological agent of dermatophytosis which accounts for 70-90% of all reported dermatophytosis cases in humans. The spread of multidrug-resistant strains of fungus and the reduced number of drugs available make it necessary to discover new classes of antifungal from natural products. Therefore the present study aimed to investigate the efficiency of the crude extracts from the leaves and bark of Croton macrostachyus, against Trichophyton rubrum, since the plant is one of the most common traditional medicinal plants used in Ethiopia. Chloroform and ethanol were employed for subsequent extraction to get crude extracts from each of the plant samples. Antifungal activity of each crude extract was evaluated at a concentration of 100, 200 and 300 mg/ml by disk diffusion method. The standard drug (Terbinafine), at 2.5 mg/ml and 1 ml of Tween 20 were used as positive and negative control, respectively. Serial dilution starting from 300 to 9.375 mg/ml was used to determine minimum inhibitory concentration. The finding in this study indicated that the chloroform and ethanol crude extract of the leaf have antifungal activity at all concentrations (100, 200 and 300 mg/ml)on Trichophyton rubrum. The crude extracts showed significant difference in the antifungal activities, as compared to the negative control (P0.05). However, Trichophyton rubrum showed more sensitivity to the leaf chloroform extract than the ethanol. Zone of inhibition of Leaf chloroform extract and Leaf ethanol extract at 300 mg/ml was higher than the positive control with mean inhibition zone of 19.00 ± 0.57 and 16.66 ± 0.88 respectively. The Minimum inhibitory concentration value of leaf chloroform extract was 18.75 mg/ml, whereas on the ethanol extract, it was 37.5 mg/ml. On the other hand, crude extracts from the bark did not show any effect on Trichophyton rubrum, having no significant difference with the negative control. The study’s findings suggest that the leaves of Croton macrostachyus have antifungal characteristics, but more emphasis should be given on the other plant part of it too.