10.22376/ijpbs.2019.10.1.p1-12 Volume 2 Issue 4 2011 (October - December) Ascidians is a rich source of bioactive secondary metabolites. lessThan i greaterThan Phallusia nigra lessThan /i greaterThan , a simple ascidian belonging to the family Ascidiidae found in plenty throughout the year along the Tuticorin coast of India. The methanolic extract of lessThan i greaterThan Phallusia nigra lessThan /i greaterThan was subjected to GC-MS analysis to determine the possible bioactive components. The analysis revealed the presence of eleven chemical constituents of which the major are: Methyl 3-bromo-1-adamantaneacetate (24.65%), n-Hexadecanoic acid (24.45%), 11-Hexadecen-1-ol,(Z)- (17.64%) and 2,6-Dimethyl-6-trifluoroacetoxyoctane (9.82%). S. Gopalakrishnan, V. K. Meenakshi And D. Shanmuga Priya Phallusia nigra, GC-MS analysis 382-387