RESEARCH ON COLLECTION AND INVESTIGATION OF ANTIOXIDANT AND ANTIBACTERIAL ACTIVITIES OF FLAVONOID EXTRACT FROM LEAVES OF Excoecaria cochinchinensis Lour

Abstract

Leaves of Excoecaria cochinchinensis Lour contain many biologically active compounds such as flavonoids, tannins, saponins, coumarins, phytosterols, free sugars... Among them, flavonoids are cell protective, antioxidant and antibacterial. The objective is to investigate maceration extraction and maceration extraction combined with ultrasound method, with conditions such as extraction solvent (water, ethanol, methanol), temperature, and ultrasonic time to obtain effective flavonoids. The extract was tested for antioxidant and antibacterial activity. The result showed that maceration extraction combined with ultrasound method obtained the highest flavonoids with maceration time of 15 hours, ultrasonic time for 20 minutes, an temperature of 60^oC. Analysis of the extract by HPLC/MS detected 14 peaks, and ESI-Micro TOF-Q mass spectrometry analysis identified kaempferol 7-o-glucoside and kaempferol, and palmitic acid. Quantification of kaempferol in the sample was based on the kaempferol standard (Sigma-Aldrich) by the HPLC/UV method. The kaempferol content was 680.5 µg/g. The antioxidant and antibacterial activities of the extract were relatively high. Research results show the potential application of Excoecaria cochinchinensis Lour in medicinal herbs and functional foods.