Effect of refrigerated storage on betacyanin composition, antibacterial activity of red pitahaya (Hylocereus polyrhizus) and cytotoxicity evaluation of betacyanin rich extract on normal human cell lines

Red pitahaya fruit is rich in purplish-red color water-soluble betacyanins. The effect of refrigerated storage at 4 °C on the betacyanin composition of red pitahaya was monitored each day, for one week, using HPLC. The betacyanin content of red pitahaya had increased by 57.2% after storage for six days at 4 °C. From day 2 to day 7, the phyllocactin content decreased from 45.4 ± 1.5% to 38.3 ± 3.1%, whereas the betanin content increased from 37.9...