Antioxidant components of the three different varieties of Indonesian ginger essential oil: In vitro and computational studies

•Emprit, gajah and red ginger are three varieties of ginger cultivated in Indonesia.•Indonesian ginger essential oil generally contains low levels of zingiberene.•Zingiberene is the main antioxidant/antiradical component in ginger essential oil.•Geranyl acetate and some monoterpenes act as antioxidants when zingiberene is low.