Efficiency of Fungal β-carotene Against Some Causative Agents of Dermatomycoses

Considering the increase of dermatomycoses and the emergence of new strains resistant to antifungal treatment, it is important to find an alternative treatment of natural origin. This study aimed to extract and purify β-carotenoid from two types of Rhodotorula diobovata and Rhodotorula mucilaginosa and test its reactivity toward some yeasts isolated from dermatomycoses infection.
Materials &

Rhodotorula samples were isolated from extreme environmental soils, and after cultivation, they were identified genetically and apparently. Then their pigments were extracted and purified. Beta-carotene was detected by ultraviolet and infrared regions. The activity of β-carotene was tested using three different concentrations using the agar diffusion method against four isolates of Candida and Cutaneotrichosporon dermatis pathogenic species by comparing its reactivity with the antifungal Nystatin.

All tested isolates, including Candida albicans HAM25, Candida dubliniensis, Candida tropicales HAM13, and Cutaneotrichosporon dermatis Judy 4, showed resistance against β-carotene purified from R. diobovata and Nystatin at the concentration 0.01mg/ml. However, β-carotene and Nystatin showed activity against all isolates with concentrations of 0.02 and 0.03mg/ml. The purified compound from R. mucilaginosa showed activity against all isolates in three concentrations, according to concentration and type. There was a significant difference between the antifungal activity of both purified β-carotene and Nystatin (p<0.0001).

Both isolates of Rhodotorula diobovata and Rhodotorula mucilaginosa produce β-carotene, and the preference quantitatively is to isolate R. diobovata first. The activity of β-carotene against all tested yeast isolates are higher than the antifungal Nystatin.