Assessment of antifungal potentials of violacein extract from Chromobacterium violaceum isolated from domestic and recreational water sources in Owerri, Imo State, Nigeria

Abstract

Anti-Microbial Resistance (AMR) in superficial fungal infections are major worldwide public health problem that affects a large part of the human population globally. The antifungal potentials of violacein extracted from Chromobacterium violaceum isolated from domestic and recreational water sources in Owerri, Imo State, Nigeria, was assessed. Three water samples were collected from different locations of the Otamiri River, five from different swimming pools and three from different borehole locations in Owerri Metropolis. The samples were cultured on nutrient agar by pour plate method. The violet colonies of Chromobacterium violaceum were counted, characterized and identified. Water sample from Otamiri River station-1 had the highest bacteria count (20.00 × 101 CFU/Ml and 19.50 × 101 CFU/mL) respectively. Swimming pool 1 and 3 bacterial counts were (14.50 × 101 CFU/mL, 11.00 × 101 CFU/mL and 11.50 × 101 CFU/mL) respectively. For borehole 1, 2 and 3, swimming pool 2, 4 and 5 counts were (0.00 × 101 CFU/mL). The ethanolic extracts from the isolates (violacein) and the control drug (fluconazole 50µg/mL) both had inhibitory effects on the test organisms (Candida albicans and Aspergillus niger) at different concentrations. The MIC of Fluconazole on Candida albicans and A. niger were 25µg/ml and 50µg/Ml, respectively. Violacein from both swimming pools and Otamiri River isolates had MIC of 8.75mg/ml on A. niger and MIC of 4.375mg/ml on Candida albicans. Violacein which proved to have inhibitory effects on Candida albicans and Aspergillus niger can be harnessed for treatment of infections caused by these fungi.