Isolation and characterization of a nitrobenzene-degrading bacterium Klebsiella ornithinolytica NB1 from aerobic granular sludge

► The strain, Klebsiella ornithinolytica NB1, was isolated from aerobic granular sludge. ► Strain NB1 could utilize nitrobenzene as a sole source of carbon, nitrogen and energy. ► Glucose or ammonium chloride could slightly enhance the biodegradation efficiency. ► Strain NB1 could degrade nitrobenzene in the presence of less than 3% NaCl.