Changes in chemical composition, minerals, total phenolic compounds and antioxidant activities during germination of sunflower sprout

Sunflower (Helianthus annuus) seeds are one of the major sources of vegetable oil in the world. Raw sunflower seeds contain high amount of fat, vitamins and minerals. Recently, in Thailand, sunflower sprouts are gaining interest because they are served as new vegetables and widely consumed as salads or stir-fried vegetables. Although, sunflower sprouts have been shown more beneficial effects than seeds due to increased levels of vitamins and minerals during germination, information on changes in minerals, total phenolic compounds (TPC), total flavonoid content (TFC) and antioxidant activities during the germination process is little. This study was aimed to determine chemical composition, minerals, TPC, TFC and antioxidant activities of sunflower sprouts during 7-day germination. Sunflower seeds were germinated at room temperature (32 degrees C) for 7 days. Minerals in germinated seeds were identified and quantified. The antioxidant activities were determined using DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical-scavenging activity and oxygen radical absorbance capacity (ORAC) assay while TPC and TFC were measured using a spectrophotometric method. Results showed that as seeding days proceeded, the content of minerals such as potassium, phosphorus, magnesium, calcium, iron and zinc were increasing. The highest amount of TPC and TFC were found at the 7th day of germination. It was also found that the antioxidant activities of germinated sunflower sprout showed the highest level on the 7th day of cultivation and a positive correlation between bioactive compounds and antioxidant activities of sunflower sprouts was observed. The results indicated that germination process can improve protein and fiber contents, minerals content and antioxidant values of sunflower sprouts. Therefore, sunflower sprout should be promoted to be included in a meal for proper diet to maintaining consumer health status.