Zoanthid is a potential natural resource with many biological activities, such as antioxidant, antiviral, antiinflammatory, and cytotoxic activity. Therefore, this study aimed to evaluate the antioxidant activity of 70% ethanol crude extract and dichloromethane fraction from Zoanthus vietnamensis. The total polyphenol content of ethanol and dichloromethane extracts were ± and ± mg GAE/g extract, respectively. | Vietnam Journal of Marine Science and Technology 2023 23 4 419 427 Vietnam Academy of Science and Technology Vietnam Journal of Marine Science and Technology journal homepage jmst Investigation of antioxidant activity of Zoanthus vietnamensis s crude extract and dichloromethane extract Phan Bao Vy Le Ho Khanh Hy Nguyen Phuong Anh Doan Thi Thiet Pham Xuan Ky Dao Viet Ha Institute of Oceanography VAST Vietnam Received 22 April 2023 Accepted 23 June 2023 ABSTRACT Zoanthid is a potential natural resource with many biological activities such as antioxidant antiviral anti- inflammatory and cytotoxic activity. Therefore this study aimed to evaluate the antioxidant activity of 70 ethanol crude extract and dichloromethane fraction from Zoanthus vietnamensis. The total polyphenol content of ethanol and dichloromethane extracts were and mg GAE g extract respectively. The DPPH free radical scavenging capacity increased slightly from low to high concentration. The IC50 values reached µg mL and µg mL for ethanol crude and dichloromethane extract. The potassium ferricyanide-reducing power assay result was meager and the optical density value ranges from to . Keywords Antioxidant activity ethanol crude extract dichloromethane extract Zoanthus vietnamensis. Corresponding author at Institute of Oceanography 01 Cau Da St. Nha Trang city 650000 Khanh Hoa Vietnam. E-mail addresses baovyphan@ https 1859-3097 18293 ISSN 1859-3097 e-ISSN 2815-5904 2023 Vietnam Academy of Science and Technology VAST 419 Phan Bao Vy et al. Vietnam Journal of Marine Science and Technology 2023 23 4 419 427 INTRODUCTION lichens. The chemical structure of MAAs has changed the position of amino acids to reach Marine resources in coral reefs are some MAAs with different physical and abundant especially in the phylum Cnidaria. chemical properties leading to adapting to harsh This group has more than 10 000 species such .
