Determinación de la actividad antioxidante y antimicrobiana de residuos de mora (Rubus glaucus Benth)

Abstract

Fruit and vegetable production generate around 1.3 billion tons per year of waste throughout the entire production chain. To add value to blackberry residues, the antioxidant and antibacterial capacity was determined with three strains of bacteria. The residues showed a high amount of the anthocyanin cyanidin-3-rutinoside (2520 mg/kg of the sample) by UHPLC analysis, titratable acidity of 1.28 %, an acidic pH 3.23, and a content of ashes of 0.45 %. The 80:20 % (v/v) hydromethanolic extract presented the highest antioxidant capacity by the DPPH method (40.53 µmol Trolox equivalents, TE), while the lyophilized extract presented a superior antioxidant capacity by the ABTS method (60.31 µmol Trolox equivalents, TE). Antibacterial activity was dependent on the concentration of the hydromethanolic extract and the type of strain (Gram-positive were most sensitive than Gram-negative), with Staphylococcus aureus being the most sensitive bacteria (15.3 mm at 8 mg/mL of extract). S. aureus and Escherichia coli presented a high sensitivity concerning the MCI (3 mg/mL and 4mg/mL, respectively).