Antibacterial activity and Fatty Acid composition of the extract from hypnea musciformis (gigartinales, rhodophyta).

The red alga Hypnea musciformis (Wulf.) Lamour., collected from the coast of Karachi, Pakistan has been studied for its fatty acid composition. Sixteen fatty acids were found in its methanolic extract, which were analysed as methyl esters by GC-MS. Altogether 7 satuated, 3 monoenoic, 2 dienoic and 4 trienoic fatty acids could be detected. Two saturated i.e. nonadecylic and heneicosanoic acids and all the 9 unsaturated acids are being reported for the first time from this seaweed. Pentadecylate was present in largest and monadecylate in smallest quantity among saturated, while decatrienoate was detected in largest and myristoleate in smallest amount among unsaturated acids. The methanolic extract of the seaweed exhibited strong antibacterial activity against the gram positive and seven gram negative bacteria, the former appeared to be more sensitive than the latter.