Global Chemical Composition and Antioxidant and Anti-Tuberculosis Activities of Various Extracts of Globularia alypum L. (Globulariaceae) Leaves

Abstract

In this work, an evaluation of the biological activities of Globularia alypum L. extracts and their global chemical composition was realized. Extracts from G. alypum were obtained by two extraction methods. The composition of polyphenols (8.5–139.95 g gallic acid equivalent/Kg of dry mass), tannins (1.39–18.65 g catechin equivalent/Kg of dry mass), anthocyanins (8.17–70.69 mg cyanidin equivalent/Kg of dry mass) and flavonoids (0.31–19.28 g quercetin equivalent/Kg of dry mass) was evaluated. The samples were subjected to a screening for their antioxidant activities using the DPPH· and ABTS·+ assays. For the first time, the anti-tuberculosis activity (H37Rv) for G. alypum was tested against Mycobacterium tuberculosis. The strongest antioxidant activity was obtained for the methanol extract (IC50 = 15.58 ± 0.168 mg/L) and the best anti-tuberculosis activity was obtained for the petroleum ether extract (IC50 = 77 mg/L). We have found a positive correlation between the total phenolics content and the antioxidant activity R2 = 0.88 (DPPH·) and R2 = 0.97 (ABTS·+). We have found also a positive correlation between the flavonoid content and the antioxidant activity R2 = 0.91 (DPPH·) and R2 = 0.91 (ABTS·+).

Keywords

• Globularia alypum L.
• polyphenols
• antioxidant activity
• anti-tuberculosis activity