Antioxidant activities of extracts from traditional Maori food plants

Abstract

New Zealand plants reportedly used as food by the early Maori may have been rich in low molecular weight antioxidants. To test this possibility, methanol‐soluble extracts from 17 indigenous and introduced plant species were challenged with the 1,1‐diphenyl‐picrylhydrazyl free radical, and scavenging efficiencies compared with that of blueberry. Antioxidant activities varied more than 150‐fold on a dry weight basis, and eight species were considerably more effective than blueberry. In contrast, crops that were used as sources of dietary starch, such as Cordyline australis and Solanum tuberosum ’Urenika’, had relatively low antioxidant activities, both raw and after boiling. Antioxidant activity did not correlate to anthocyanin content. Our data indicate a remarkable potential of some New Zealand species as sources of dietary antioxidants.

Key words:

• antioxidants
• flavonoids
• New Zealand plants
• functional foods
• Maori diet