Then the medium was sterilized by autoclaving at 121 °C and at 15 lb for 15 min. After sterilization, the medium and sterile Petri plates were transferred into laminar air flow chamber. Approximately 15-20 mL of the sterile medium was poured in each sterile Petri plates. The medium was allowed to solidify in laminar flow and inoculated with the overnight bacterial cultures.