The best advice is to not eat it. It was eaten by Aborigines after a long involved preparation process. But you need to remember that not all toxins are removed by these processes. One of the reasons they're free of pests and diseases is because of the toxins they contain, an evolutionary defence against things that try to eat them. You're better off going for some of the varieties of Alocasia macrorrhizos that have had most of the toxins bred out of them during thousands of years of cultivation. Burke and Wills hastened their deaths by eating some native foods they had no idea how to prepare properly.