Synthèse bibliographique des méthodes d’extraction des flavonoïdes et leurs rendements chez les Brassicaceae.

Abstract

Lobularia maritima (L.) Desv. Very abundant in Algeria, is a perennial herbaceous plant of the family Brassicaceae. It grows wild in the Mediterranean basin. The aim of this work was to compare the quantity of flavonoids extracted between Lobularia maritima and some other medicinal plants. The present work is a synthesis study on a phytochemical screening of total phenols, on flavonoids as the most important class of the polyphenol family and on antioxidant activity. This study concerns three plant extracts. The extraction is done by two methods "decoction and maceration", the first is a methanolic extract obtained by decoction of Matricaria recutita which is an Asteraceae, the second aqueous extract by decoction of Zilla macroptera and the third methanolic extract obtained by maceration of Lobularia maritima which are both Brassicaceae. The research results show that the M. recutita species has total phenolic compound contents of 3.99 g/ 100 g dry weight, flavonoids 2.59 g/ 100 g dry weight and has an antioxidant activity of 344.02-± 18.65 μg/ml. The aqueous extract of Z. macroptera has shown that the level of total phenolic compounds is 89 ± 2.46 μg/mg. It is even lower for total flavonoids 12.99±0.67 μg/mg. The antioxidant activity of the same aqueous extract is 0.26 ± 0.04 mg/ml. Finally, L. maritima showed a content of 86.2 ± 0.8 mg/g of phenols and a level equal to 17.85 ± 0.04 mg/g of flavonoids. Its antioxidant activity is 937.70 ± 8.07 μg/ml. The different methods compared give very different levels of flavonoids and phenolic compounds and therefore different antioxidant activities.