TOTAL POLYPHENOL CONTENT AND ANTIOXIDANT CAPACITY IN JUICE AND PEEL OF BLUEBERRIES (VACCINIUM CORYMBOSUM) GROWN IN CAÑETE VALLEY, PERU

• Published in: Annals of nutrition and metabolism 2017-10, Vol.71 (Suppl. 2), p.390
• Main Authors: Prado, Elena Elizabeth Lon Kan, Ticlayauri, Edwin Antonio Macavilca, Prado, Carlos Alberto Lon Kan, Chipana, Carlos Canchos, Veramendi, Jyothisa Eva-Gina Reyes
• Format: Article
• Language: English
• Subjects: Acetone; Aging; Antioxidants; Berries; Blueberries; Cancer; Cellular structure; Distilled water; Ethanol; Free radicals; Fruits; Gallic acid; Juices; Methanol; Molecular chains; Nutrition; Polyphenols; Solvents; Stability; Structural damage; Temperature effects; Vaccinium corymbosum; Vitamin E
• ISSN: 0250-6807; 1421-9697
• DOI: 10.1159/000480486

Background and objectives: Blueberries are considered as the king of antioxidant foods, due its high content that protects our bodies from damage by free radicals, unstable molecules that can damage cellular structures and contribute to aging and diseases like cancer. The aim of the present study was to determinate the total polyphenol content and antioxidant capacity of juice and peel from blueberries (Vaccinium corymbosum) grown in Cañete Valley, Peru. Methods: Folin-Ciocalteu and DPPH methods were used to determinate the concentration of total polyphenol content and antioxidant activity, respectively. Extracts were obtained from juice and peel in four study parameters. At first, solvents with different polarities were tried (water, methanol, ethanol 80% and acetone-water 75%); second, ratio fruit/solvent; thirth, extraction- time and fourth, temperature. Results: Results in juice: total polyphenol content 3,474 mg Gallic acid/ml juice and antioxidant capacity 12,131 Trolox mg/ ml juice. Results in peel: showed solvent acetone/water 75% > ethanol/agua 80% > methanol > distilled water. The ratio 1/10 was greater ratio 1/12. 4 hours-time exhibed the higher values in total polyphenol content 16.40 mg Gallic acid/ml extract and antioxidant capacity 8,90 mg Trolox/g blueberries. The effect of temperatures were studied between 40 to 80 °C. At 60, 70 and 80 °C showed higher total polyphenol content values: 19,213; 26,522; 32,830 mg Gallic acid/ml extract, respectively; however the stability and antioxidant capacity were reduced when increased the temperature: 13,500; 13,675 and 12.525 mg Trolox/g peel, respectively; and at temperatures below about 40-50 °C the total polyphenol content and the antioxidant capacity showed higher stability. It is concluded that the peel has higher total polyphenol content and antioxidant capacity than the juice and fresh whole fruit. Conclusions: The stability and antioxidant capacity were reduced when increased the temperature (13,500; 13,675 and 12.525 mg Trolox/g peel, respectively). At temperatures below about 40-50 °C the total polyphenol content and the antioxidant capacity showed higher stability. It is concluded that the peel has higher total polyphenol content and antioxidant capacity than the juice and fresh whole fruit.