In this work, a laccase from Cerrena Unicolor (CuL) supplied by Fungal Bioproducts® was firstly applied in combination with VA in Eucalyptus globulus in order to compare its biobleaching effect with the well-known laccase from Trametes villosa supplied by Novozymes®. However, the main purpose of this work was to apply the CuL in presence of two different mediators like VA (as synthetic compound) or p-coumaric acid (PCA), acetosyringone (AS) or syringaldehide (SA) (as natural compounds). Each compound was applied alone or in combination with another one in order to find a possible biobleaching or functionalising boosting effect between them. Concerning the biobleaching effects, the highest delignification and brightness increase was produced with the VA applied alone. The natural mediators failed to increase delignification and contrary, they hindered the effect of VA due to possible interactions with the natural phenols and fibres. Concerning the grafting effects, the highest increase in kappa number and in colour properties was produced with the combination of PCA and AS. Finally, the best way of applying these mediators, together in one step (LAS+PCA), or in two steps with (LASwashing-LPCA) or without (LAS-LPCA) washing was evaluated