Tomato waste: A potential source of hydrophilic antioxidants

Abstract

Waste obtained from six genotypes of tomato was subjected to evaluation as potential sources of hydrophilic antioxidants on the basis of content of total phenolics (TPh; from 11.7 to 18.6 mg/g), total flavonoids (TFl; from 7.62 to 12.1 mg/g) and ascorbic acid (AA; from 0.51 to 1.89 mg/g), and antioxidant activities. The antioxidant activities of tomato waste extracts were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferrous ion chelating activity (CA) and reducing power (RP) assay. The O₂ tomato waste extract was found to have the strongest antioxidant activity in scavenging DPPH radicals (effective concentration, EC₅₀ = 0.18 mg/ml). The Saint Pierre tomato waste extract showed the best performance in RP assay (EC₅₀ = 1.57 mg/ml). The Rutgers tomato waste extract exhibited a strongest CA (EC₅₀ = 1.49 mg/ml). The linear correlation analysis produced moderate-to-high correlation coefficients between the antioxidant activities and TPh, TFl and AA.

Keywords::

• tomato waste
• hydrophilic antioxidants
• DPPH assay
• reducing power
• chelating activity

Declaration of interest: This research is part of the Project TR 31044, which is financially supported by the Ministry of Education and Science of the Republic of Serbia. The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.