The main inclusion criteria are :age 18 years or older, presence of sinus rhythm on the screening electrocardiogram, first-time elective open heart surgery. Exclusion criteria are: absence of sinus rhythm at screening, known allergy or intolerance to gluten or anthocyanin compound, regularly consuming of anthocyanin or antioxidant supplements, being currently pregnant, existing or planned cardiac transplant or use of ventricular assist device, or being unable or unwilling to provide informed consent, known history of hepatic or renal disease, cancer and subjects with a history of substance abuse.