Influence de différentes méthodes d’extraction sur le rendement, la composition chimique et l’activité antioxydante des extraits de zingiber officinale (Formes fraiche & sèche).

Abstract

This work is a contribution to the valorization medicinal and aromatic plants. Zingiber officinale is an Asian plant, known by its properties and medicinal virtues all over the world. Several extraction methods are applied to the two forms of the ginger rhizome ; fresh and dried, namely sonication, superheated water extraction and Soxhlet extraction. It is noted that the extraction method significantly influences the yield and the nature of the extracted molecules. The best yield is recorded by extracts from sonication (85% for fresh ginger and 86% for dried ginger). The results show a clear difference between the extracts of the two forms fresh and dried, as well on the extraction yield as on the extracted molecules revealed by the phytochemical screening tests. The antioxidant power denoted by the free radical reduction test DPPH *, shows a variation of effectiveness of the antioxidant activity, this depending on the extraction techniques applied. The extract from the superheated water extraction technique for 10 minutes (dried form) proved the highest antioxidant power 89.54%.