Antioxidant, antibacterial and antitumoural activities of kraft lignin from hardwood fractionated by acid precipitation

Kraft lignin, so far useful for energy generation, has been gathering considerable attention as an alternative material to replace fossil-based resources mainly due its high phenolic content. However, the wide molecular weight distribution and chemical composition heterogeneity led development of fractionation methods. Herein, narrow such characteristics we used eucalypt kraft lignin fractionated at pH's 9, 7, 5 3 by sequential acid precipitation. These fractions were first characterised simultaneous pyrolysis trimethylsilylation (SPyT) with N-Methyl-N-(trimethylsilyl) trifluoroacetamide posterior tests antioxidant, antibacterial, antitumour activities. We observed higher ratio syringyl/guaiacyl groups increase in antioxidant activity those lower (precipitated pH's). Fractions precipitated 9 7 have shown outstanding antibacterial against five bacteria. Moreover, presented cytotoxicity ability inhibit growth U87MG T98G glioma cells, while only a slight inhibition adult human fibroblasts (non-tumour cells) was detected.