Bioactive Compounds and Antioxidant Activity in Leaves of Endemic and Native Isatis spp in Turkey

Abstract

Abstract This study was undertaken to evaluate the health-promoting potentials of Isatis aucherii, Isatis buschiana, Isatis candolleana, Isatis tinctoria subsp. corymbosa and Isatis tinctoria. I. aucherii and I. candolleana are endemic, I. buschiana, I. tinctoria subsp. corymbosa are native in Turkey. While I. tinctoria is a well studied species, there is insufficient information about other endemic and native species. Therefore, this study is focused to reveal the bioactive compounds of poorly studied endemic and native species. In this context, protein, ash, glucosinolates, fatty acids, total phenolic and flavonoid content, and antioxidant activities were determined in leaf extracts. The highest protein and fatty oil contents were observed in I. tinctoria and I. buschiana. Arachidic acid was predominant inI. tinctoria subsp. corymbosa, I. buschiana and I. aucherii, while predominant fatty acids were arachidonic and oleic acids inI. candolleana and I. tinctoria. Glucobrassicin was the main glucosinolate in I. tinctoria, while the others contained gluconapin as the main glucosinolate. Antioxidant activities were correlated with phenolic and flavonoid content, the highest and lowest antioxidant activities were observed in I. buschiana and I. aucherii, respectively. According to results, I. buschiana leaves were high in contents of bioactive compounds; it could be a promising plant with its health- promoting effects.

Keywords

• Antioxidant activity
• fatty acids
• flavonoid
• glucosinolate
• Isatis
• phenolic