10.22376/ijpbs.2019.10.1.p1-12 Volume 4 Issue 2 2013 (April - June) Anti-mycobacterial bioactivity of non polar compounds from red algae lessThan i greaterThan Euchema spinosum lessThan /i greaterThan of Barang Lompo Island was studied. A triterpenoid carbocylic acid has been isolated from the chloroform fraction of lessThan i greaterThan Euchema spinosum, lessThan /i greaterThan and its structure was determined by spectroscopic evidences including IR and 2D NMR and compared to previous data. The isolate was active against lessThan i greaterThan Mycobacterium tuberculosis lessThan /i greaterThan at concentration 4 µg/mL, and could also increase the sensitivity of this pathogen to isoniasid drug. These studies suggest that anti-mycobacterial triterpenoid carbocylic acid in combination with isoniasid may play an important role in host defence against lessThan i greaterThan M. tuberculosis lessThan /i greaterThan strain H37Rv. AHYAR AHMAD AND MUH. NASRUM MASSI Red algae, Euchema spinosum, Triterpenoid carbocylic acid, Antimycobacterial activity. 231-237