Changes in bioactive phytochemical content and in vitro antioxidant activity of carob (Ceratonia siliqua L.) as influenced by fruit ripening

In the present study, three varieties (Wild, Fleshy and Sisam) of carob (Ceratonia siliqua L.) pods were analyzed for their bioactive phytochemical content and antioxidant activities (AA) at three ripening stages. The results showed that the samples have the highest total phenolic (TPC), total flavonoid (TFC) and ascorbic acid content (AAC) in the unripe stage. The antioxidant activity examined using free radical scavenging effect against 2-2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing power (FRP) and ferrous iron chelating (FIC) assays decreased significantly throughout the ripening. Extremely significant correlations (p < 0.001) were found between phytochemical compound contents (TPC,TFC and AAC) and assessed antioxidant activities, except between AAC and FIC where just a very significant correlation (p < 0.01) was recorded. Our data revealed that extracts of unripe C. siliqua L are an excellent source of natural antioxidants that might be more widely used in cosmetic, pharmaceutical and food industries. (C) 2014 Elsevier B.V. All rights reserved.