The in vitro evaluation of antioxidative activity, α-glucosidase and α-amylase enzyme inhibitory of natural phenolic extracts.

Phenolic extracts from the medicinal parts of six traditional Algerian herbs were tested in screening experiments for the antioxidant, α-amylase and α-glycosidase inhibiting activities. UV-analysis of the extracts from the plants indicated that the total phenols content was ranged between 0.48 and 3.46 mg equivalent of gallic acid per gram of dry matter, whereas the flavonoids content expressed as rutin equivalent per gram of dry matter was ranged between 0.18 and 2.23 mg/g. The study of antioxidant activity by scavenging the hydroxyl radical (OH), the nitroxide radical (NO) and the stable radical cation (ABTS(+)) showed a high antioxidant power. Also, these extracts illustrated a significant reductive power of the Fe(3+)-TPTZ complex. Similarly, we have found that the phenolic extracts exhibit an imperative antioxidant status compared to synthetic antioxidants. The study of the extract effects shows that Anabasis articulata, Agatophora alopecuroide and Heliantheum kahiricum extracts have a powerful inhibiting capacity of the α-amylase and α-glycosidase with a Ki values less than 10 μM. Our study, for the first time, revealed the anti-diabetic potential of the six plants and the results of this study could be helpful to develop medicinal preparations or nutraceuticals and functional foods for diabetes.