Antioxidant capacity and total phenolics compounds fo twelve slected potato landrace clones grown in southern Chile.

Kong Ah-Hen1, Carlos Fuenzalida2, Sergio Hess3, Andres Contreras2, Antonio Vega-Gálvez4*, Roberto Lemus-Mondaca4,5

Colored potatoes (Solanum tuberosum L.) provide a natural source of phytochemicals that help reduce the risk of diseases. However, there is a lack of information on the degree of variation of the antioxidant activity and polyphenolic contents of these native potatoes. Thus, the antioxidant activity (AA) and total phenolic content (TPC) of native Chilean potatoes were determined. Twelve potato landrace clones collected from established cultivations on Chiloe Island and Valdivia were selected. Total phenolic content and AA were compared with two commercial varieties, Shepody and Desirée. Total phenolic content was determined by the Folin-Ciocalteu method, and β-carotene bleaching was used to compare AA. The TPC varied in the peeled potato samples from 191 to 1864 mg 100 g-1 DM meanwhile these parameters varied from 345 to 2852 mg 100 g-1 DM in unpeeled samples. Antioxidant activity was higher in unpeeled potatoes, and was the highest in the unpeeled NG-6 or ‘Bruja’ native potato. The commercial var. Shepody showed pro-oxidant activity and had a relatively lower TPC. Results also indicated a higher concentration of total phenolics in the periderm of the colored native Chilean potatoes.

Keywords: Chilean potatoes, Solanum tuberosum, antioxidant activity, total phenolics, Folin-Ciocalteu, â-carotene.
1Universidad Austral de Chile, Instituto de Ciencia y Tecnología de los Alimentos, Av. Julio Sarrazín sn, Campus Isla Teja, Valdivia, Chile.
2Universidad Austral de Chile, Instituto de Producción y Sanidad Vegetal, Av. Eduardo Tallman sn, Campus Isla Teja, Valdivia, Chile.
3Universidad Austral de Chile, Instituto de Química, Las Encinas sn, Campus Isla Teja, Valdivia, Chile.
4Universidad de La Serena, Departamento de Ingeniería en Alimentos, Av. Raúl Bitrán sn, La Serena, Chile. *Corresponding author (avegag@userena.cl).
5Universidad de Santiago de Chile, Departamento de Ingeniería Mecánica, Av. Bernardo O’Higgins 3363, Santiago, Chile.