Antibacterial activity of roselle calyx extracts, sodium hypochlorite, colloidal silver and acetic acid against multidrug-resistant salmonella serotypes isolated from coriander

Multidrug-resistant Salmonella serotypes (M-RSs) were isolated from coriander, and an analysis done of the antibacterial activity of roselle calyx extracts against any of the identified strains. One-hundred coriander samples were collected from markets. Salmonella was isolated from the coriander samples by culture procedure. Susceptibilities to sixteen antibiotics were determined for the isolated Salmonella strains by standard test. The antibacterial effect of four roselle extracts (water, methanol, acetone and ethyl acetate), sodium hypochlorite, acetic acid and colloidal silver against M-RS isolates was evaluated on contaminated coriander. Thirty-one Salmonella strains were isolated from 23% of coriander samples. Identified Salmonella serotypes were typhimurium, typhi and montevideo. All isolated strains exhibited resistance to at least three antibiotics. Roselle extracts caused a greater reduction in concentration of M-RSs than the sodium hypochlorite, colloidal silver and acetic acid on contaminated coriander. Roselle calyx extracts may be a potentially useful addition to disinfection procedures of coriander.