Capacidad antioxidante de dos variedades de Fragaria x ananassa (Weston) Duchesne (fresa) sometidas a variaciones en la nutrición vegetal

introduction: the strawberry belongs to rosaceae family, being a source of polyphenolic compounds with antioxidant activity, specially anthocyanins, phenolic acids and vitamin c, which protect many organelles from oxidation. strawberries have more antioxidant activity than many fruits such as grapefruit, orange, red grape and kiwi. however, the secondary metabolites in strawberry can be potentiated by a controlled dosage of nutrients into the soil. objectives: to evaluate the antioxidant activity, anthocyanin content and total phenolic content of two varieties of strawberry (camarosa and osogrande) by changing nutrition of soils using nitrogen, potassium, phosphorus, sulfur, calcium, magnesium and organic matter, in order to establish the relationship between levels of fertilization and the response of antioxidant capacity. methods: the antioxidant properties and some polyphenolic components of the aqueous strawberry extracts from the region of antioquia and grown in colombia (camarosa and osogrande). the total phenolic content was determined by the follin ciocalteu′s method, the anthocyanins by the ph differential method and the antioxidant activity by dpph assay. results: the 2-2-1-1 experimental unit (camarosa) showed antioxidant activity of ci50 65.90 mg in dried fruit, the total phenolic content was 984.75 and anthocyanin content ranged from 83.18 to 92.83, these figures were higher than those found in temperate zones. conclusions: the 2-1-1 experimental unit camarosa, with higher levels of organic matter and lower levels of mineral nutrients, had the greatest antioxidant activity, thus increasing its therapeutic options, and keeping good phenotypical response.