The antibacterial activity from non-hydrogen peroxide of honey was determined by the addition of catalase. Hydrogen peroxide in the honey was decomposed into water and oxygen by catalase. Firstly, the catalase solution was prepared by adding the 20 mg catalase (Sigma, USA) into 10-mL sterile deionized water, and then the solution was properly mixed. Stock solution of 50% honey sample was prepared by weighing 5g of honey and was added into 10mL of sterile distilled water.[23 (link)] Two clean test tubes were labeled as A for catalase-treated honey and B for catalase-untreated honey. Subsequently, 1mL of 50% honey and 1mL of catalase solution were added into tube A to produce 25% catalase-treated honey. Meanwhile, 1mL of sterile distilled water was added into tube B to produce 25% catalase-untreated honey.