BIOCHEMICAL CHARACTERIZATION OF BORAGE (Borago Officinalis L)

Abstract

Borage (Borago officinalis) is an annual herb which is cultivated for medicinal and culinary uses. The present work details the biochemical characterization of borage. We tested the antioxidant activity in-vitro, using the DPPH test. Our results, also, showed that the different parts analysed contain very high levels of total polyphenols. Indeed, the leaves are characterized by the highest concentration (3.42±0.24 mg EAG/g MS), followed by the flowers (2.65±0.28 mg EAG/g MS) and the stems (2.25±0.03 mg EAG/g MS). In addition, the total flavonoid contents of Borago Officinalis L. vary significantly depending on the organ studied. The stems are characterized by the highest concentrations (437.87±32.14 mg Eq Q/g MS), whereas the flowers represent the lowest concentrations (333.33±38.56 mg Eq Q/g MS). The analyses of Total tannin have shown that the highest contents (592.53± 46.18 mg EqAT/g MS) are observed in the stems, while the leaves and flowers had similar concentations. (413.68±21.99 mg EqAT/g MS, for flowers; 454.12±17.59 mg EqAT/g MS for leaves). Analyses of condensed tannins have shown that the aqueous extract of the Borago Officinalis L. stem, is cacerized by the highest rates (99. 54±0.64 mg EqCAT/g MS), the leaves and the flowers have average rates (53.63±3.85 mg EqCAT/g MS and 82.27±5.78 mg EqCAT/g MS, respectively). Antioxidant activity was evaluated by the DPPH test. In the three extracts studied, it was observed that the percentage of inhibition (IC50) of the DPPH radical increases as function of the concentration and that the three extracts have a high antioxidant capacity. This is reflected in low IC50 values, which oscillated between (104.78±2.54 µg/ml), and (125.45±3.97 µg/ml), in aqueous extract of stem and of flowers, respectively. However, the anti-radical, of various extracts, remains lower, compared to that of ascorbic acid (IC50=73.15±5.12µg/ml), Used as a reference molecule.