Determination of Phenolics, Antioxidant Activity and Antidiabetic Potential of Sphagneticola calendulacea (L.) Pruski Leaves Grown in Vietnam

Abstract

Sphagneticola calendulacea (L.) Pruski, a member of the Asteraceae family, is commonly found growing in India, Sri Lanka, China, and Southeast Asian countries. It has been utilized in traditional medicine for treating various illnesses in many Asian nations. The objective of this research was to compare the phenolic content, antioxidant activity, and inhibitory effect on α-glucosidase of S. calendulacea leaf extracts obtained through conventional solvent, ultrasound, and enzyme-assisted methods. Eight phenolic compounds were quantified in the extracts, and the results revealed that the methanol extract comprised the greatest amount of phenolic compounds (228.10 µg/ml) in comparison with the other extracts. The extract from the ultrasound method exhibited the highest ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) antioxidant activity. The ethanol extract presented the strongest inhibition of α-glucosidase. Generally, the applications of ultrasound and enzyme to extraction helped enhance phenolic content and bioactivities of the resulting extracts. These findings give a deeper insight into the phenolics and health endorsing activities of S. calendulacea leaves, which is beneficial for the development of new drugs for disease prevention and treatment.