Dynamics of anthocyanin profiles of the fruits of four blueberry ( Vaccinium sp.) cultivars during different growth stages

Blueberries are particularly rich in anthocyanins and are favored extensively for their health benefits. In this study, the anthocyanin profiles of fruits of four blueberry cultivars (Gardenblue, Legacy, Misty, and Brightwell) were investigated. Total anthocyanin content gradually increased in all four cultivars during development, but mature fruits of Brightwell and Gardenblue had a higher anthocyanin content than those of Legacy and Misty. Thirty-two kinds of anthocyanins were quantified using UPLC-ESI-MS/MS. Principal component analysis showed that the anthocyanin profiles of Gardenblue and Legacy were similar to those of Misty and Brightwell, respectively. Levels of malvidin 3-O-galactoside, malvidin 3-O-glucoside, malvidin 3-O-rutinoside, delphinidin 3-O-glucoside, delphinidin 3,5-O-diglucoside(delphin), petunidin 3-O-glucoside, and petunidin 3-O-rutinoside in mature fruits of Gardenblue were higher than those in the other three cultivars. The content of delphinidin 3-O-(6”-O-malonyl)-beta-D-glucoside, petunidin 3-O-(6-O-malonyl-beta-D-glucoside), petunidin 3-O-arabinoside, delphinidin 3-O-arabinoside, and delphinidin 3-O-galactoside was the highest in mature fruits of Misty. Levels of petunidin 3,5-diglucoside and petunidin 3-O-galactoside in mature fruits of Brightwell were higher than those in the other three cultivars. Quantitative real-time reverse transcription-polymerase chain reaction analysis showed that ANS, F3ʹ5’H, and UFGT were preferentially expressed in fruits of Gardenblue, possibly attributing to higher levels of delphinidin 3-O-glucoside and delphinidin 3,5-O-diglucoside (delphin) in this cultivar. This study adds to our knowledge of anthocyanin content and profiles in the four important blueberry cultivars grown in China.