The aim of this study was to evaluate bioactive
compounds in five apple cultivars and to analyze correlation
of their quality characteristics with concentration of bioactive
compounds. Phenolic compounds measurements were made in a
spectrophotometer compared to a standard curve of gallic acid
and expressed as gallic acid equivalent (GAE) per 100g of dry
weight. Sugar and organics acids in five cultivars were quantified
using high-performance liquid chromatograph (HPLC).
Antioxidant activities were evaluated using three complementary
tests 2,2-diphenyl-1-picrylhidrazyl (DPPH) scavenging activity,
ferric reducing antioxidant power (FRAP), and 2,2’-azino-bis
(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS). ‘GoldRush’ had
the highest total phenolic compared to the other four cultivars.
Additionally, ‘GoldRush’ had slightly higher, DPPH activity
followed by ‘Crimson Crisp’ and ‘Wine Crisp’. ‘GoldRush’ and
‘Crimson Crisp’ cultivars also have higher antioxidant capacity
based on the ABTS and FRAP methods. The antioxidant capacity
was significantly correlated with total polyphenols present in the
different cultivars, while organic acids and fruit color showed
slightly significant correlation to total phenols