Antibacterial property of blue gum (Eucalyptus globulus ) essential oil against Staphylococcus aureus in Philippine native chicken

Abstract

<i>Staphylococcus aureus</i> is a gram-positive bacterium that can cause septicemia and affection of the skin, joints, as well as sepsis and death in poultry animals. It is the most common cause of bumblefoot in chickens. <i>Eucalyptus</i> is rich in substances such as 1,8 cineole, terpenes and phenolic compounds that are responsible for inhibiting bacterial growth. The study was conducted to assess the minimum inhibitory concentration and zone of inhibition as well as evaluation of the concentration of <i>eucalyptus</i> oil according to potency. This research involved a total of 30 Petri plates, 100µl <i>Staphylococcus aureus</i> bacteria, 500µl tylosin at higher dose, 250µl tylosin at lower dose, 500µl VCO, 500µl distilled water. The concentrations were laid out using a complete randomized design (CRD) and two-factor (CRD). The EEO assessed through MIC after 24 hours of post exposure revealed that 100% EEO concentration has the highest mean percentage (62.20%). In addition, treatments 85% to 100% EEO concentration had a wider ZOI. Furthermore, the results show that the antibacterial potency of Blue Gum (<i>Eucalyptus globulus</i>) against <i>Staphylococcus aureus</i> is 75.32%, which means that the antibacterial property of EEO is potent, based on standard potency of 60 to 150 percent. Thus, EEO can act as an alternative in controlling <i>Staphylococcus aureus</i> isolated from Philippine Native Chicken.