Published online by Cambridge University Press: 12 September 2013
Introduction.Strawberry is rich in health as well as bioactive compounds, andbenefits resulting from the use of natural products rich in bioactivesubstances are receiving increased interest from the pharmaceutical,food and cosmetic industries. Materials and methods.Twenty-two cultivars of strawberry (Fragaria × ananassa Duch.) grown under a temperate ecosystemwere screened for ascorbic acid, phenolic compounds, flavonoids,anthocyanins and antioxidant activities (DPPH and FRAP assays).The phenolic content was measured by Folin-Ciocalteu reagent usinggallic acid as the standard. Antioxidant activity was determinedin terms of DPPH and FRAP assays and expressed as ascorbic acidequivalent. Total anthocyanins and total flavonoid content weredetermined using a colorimetric method. Titratable acidity (citricacid) was determined by the titration method. The average data oftwo years was analyzed using SAS 9.2 software. Results and discussion.Significant differences in the health and bioactive compounds weredetected among the cultivars. The range of ascorbic acid of thetested samples was (51.03 to 89.40) mg·100 g–1 fresh weight. Titratableacidity varied between 0.73% and 1.44%; however, total anthocyanins rangedbetween (28.24 and 43.32) mg cyanidin-3-glucoside Eq·100 g–1 freshweight. Total phenols varied from (380.10 to 888.10) mg gallic acidEq·100 g–1 and total flavonoids from (31.26 to 55.16) mg catechinEq·100 g–1. The total antioxidant activity ranged between (203.13 and471.10) mg ascorbic acid Eq·100 g–1 fresh weight for DPPH, and between (326.06and 701.13) mg ascorbic acid Eq·100 g–1 fresh weight for FRAP. Totalphenols, DPPH and FRAP showed close association; however, PCA clearlycategorized the selected cultivars intotwo broad groups.All of the diverse cultivars were clustered into two clusters which couldbe exploited for future qualitative breeding programs based on average clusterdistance and can act as gene sources for making health foods. Conclusion.The importance of our findings would be significant for farmers,breeders, consumers and industries concerning food quality, diseaseprevention and healthcare.