Obtaining phenolic compounds by sugar cane bagasse pyrolysis and its antioxidant capacity measured through chemical and electrochemical methods

Pyrolysis under low temperature (<380 degrees C) was used to obtain phenolic compounds from sugar cane wastes (bagasse). Total phenolic composition in the bio-oil was determined by Folin-Ciocalteu assay. Mean values of 1,78 and 4,26 mg EAG/g bagasse were obtained. GC-EM analysis of the obtained bio-oil gave mostly 4-ethyl-2-metoxyphenol; 4-ethyl-2-metoxyphenol isomers and 3-propylphenol. Antioxidant capacity was measured using two methods: chemical or 2,2-dipheni1-1-picrylhydrazyl (DPPH) free radical capture with results as 227 mu g/mL for bio-oil and 595 mu g/mL. for bagasse water extract; and by electrochemical method using cyclic voltammetry. Last resulted in an irreversible process giving scanning of cathodic force at 0.98 V (vs Ag0/+). The results reveal the antioxidant activity in good qualitative agreement with the experimental report [1]. Bio-oil showed a high phenolic content and a good antioxidant capacity, that is a potential source for obtaining antioxidants that could be used in polymer, cosmetic and pharmaceutical industries.