The gliding arc discharge plasma reactors are known as a source of non-equilibrium plasma at atmospheric pressure. In the present study, generation of dominant reactive oxygen and nitrogen species in gaseous and liquid phase in water by the compact gliding arc device (mini-GAD) and corresponding bactericidal effects were investigated. Water and phosphate buffer solutions were used as model liquids. Mini-GAD is a strong source of nitrogen oxides (up to 800ppm NO and 200ppm NO2) that result in high concentrations of nitrites and nitrates in water solutions. The highest bactericidal efficacy towards Escherichia coli was achieved for non-buffered water solution.