 The laccase, a polyphenol oxidase and an enzyme oxidating urishiol and laccol obtained from the lacquer tree, was first studied by Gabriel Bertrand in 1894.Bertrand's rule refers to the fact that the dose–response curve for many micronutrients is non-monotonic, having an initial stage of increasing benefits with increased intake, followed by increasing costs as excesses become toxic.In 2005, Raubenheimer et al.