Vi nấm biển được xem là nguồn tiềm năng sinh các hợp chất tự nhiên có hoạt tính sinh học như kháng sinh, kháng viêm, kháng ung thư và chống oxy hóa. Trong nghiên cứu này, cặn chiết ethyl acetate thô của 117 chủng vi nấm phân lập từ vùng biển Nha Trang đã được đánh giá hoạt tính kháng sinh và khả năng khử gốc tự do DPPH (2,2-diphenyl-1-picrylhydrazyl) và ABTS (2,2’- azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)). | TAP CHI SINH HOC 2019 41 2se1 amp 2se2 409 417 DOI 0866-7160 v41n2se1 amp EVALUATION OF ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF MARINE FUNGI ISOLATED FROM NHA TRANG BAY Phan Thi Hoai Trinh Tran Thi Thanh Van Ngo Thi Duy Ngoc Cao Thi Thuy Hang Le Thi Hoa Dinh Thanh Trung Huynh Hoang Nhu Khanh Le Dinh Hung Nha Trang Institute of Technology Research and Application VAST Vietnam Received 12 August 2019 accepted 28 September 2019 ABSTRACT Marine fungi are considered as a potential source of natural compounds such as antibiotics anti- inflammatory anti-cancer and anti-oxidants. In the present study crude ethyl acetate extracts of 117 fungal strains isolated from Nha Trang Bay were evaluated for antimicrobial activity DPPH 2 2-diphenyl-1-picrylhydrazyl and ABTS 2 2 -azino-bis 3-ethylbenzothiazoline-6-sulphonic acid radical scavenging activities. The results showed that there were n 74 fungal strains exhibited inhibitory activity against at least one test microorganism strain with the diameter of of inhibition zone from 7 mm to 31 mm. The study also indicated that crude extracts from the collected marine fungi were able to reduce DPPH and ABTS free radicals with the rate of n 72 and n 111 respectively. The strains with high antibiotic and antioxidant activity were classified based on sequence analysis of the ITS Internal transcribed spacer region. This screening is the basis for further studies on isolation and obtaination of bioactive natural metabolites from promising marine fungal strains. Keywords ABTS antimicrobial activity DPPH marine fungi natural compounds. Citation Phan Thi Hoai Trinh Tran Thi Thanh Van Ngo Thi Duy Ngoc Cao Thi Thuy Hang Le Thi Hoa Dinh Thanh Trung Huynh Hoang Nhu Khanh Le Dinh Hung 2019. Evaluation of antioxidant and antimicrobial activities of marine fungi isolated from Nha Trang Bay. Tap chi Sinh hoc 41 2se1 amp 2se2 409 417. https 0866-7160 v41n2se1 amp . Corresponding author .