STUDY ON ANTIOXIDANT AND ANTIBACTERIAL PROPERTIES OF ETHANOL EXTRACT FROM Caulerpa racemosa AT KIEN GIANG PROVINCE

Abstract

The ethanol extract from the green algae Caulerpa racemosa collected at Hon Son island, Kien Giang province was initially investigated its chemical compositions, and evaluated its antioxidant and antibacterial activities. The antioxidant activity of the ethanolic extract C. racemosa was determined by methods of DPPH (2,2-Diphenyl-1-picrylhydrazyl), ABTS (2,2'-Azinobis 3-ethylbenzthiazoline-6-sulfonic acid), phosphomolybdenum and RP (Reducing power). The results indicated that ABTS and phosphomolybdenum method showed highest antioxidant activity with EC₅₀ values ​​of 174±3.48 µg/mL anh 206±1.07 µg/mL, respectively. The antimicrobial activity was investigated on six strains of human pathogenic bacteria. This result demonstrated that the extract was effective in antibacterial activity against four strains of Bacillus subtilis, Bacillus cereus, Listeria innocua, and Staphylococcus aureus. In addition to these biological activities, the study also examined phenolic and flavonoid total contents in the extract with amounts of 56.7±2.34 mg GAE/g and 128±2.69 mg QE/g, respectively. From these preliminarily experimental results, the extract of green algae Caulerpa racemosa has potential applications in production of pharmaceuticals and functional foods.