Elemental and metabolite profiling of nickel hyperaccumulators from New Caledonia

► Nine species were studied from New Caledonia with leaf Ni concentrations between 250-28,000 mg/kg dw. ► Elemental profiling using ICP-OES showed these plants maintain their metal ion homeostasis. ► GC-MS profiling found a number of correlations between nickel and small molecule metabolites. ► LC-MS detected a range of Ni-complexes with these metabolites. ► Psychotria douarrei had the highest malonic acid level and Ni-malonate was detected by LC-MS.