547.915The composition of the lipophilic extract from the two specimen of the sponge Axinella carteri (Dendy) collected from two different depths of the Bay of Bengal of the Orissa coast were investigated. Fatty acids, as well as volatile compounds and sterols, were identified. A high concentration of polyunsaturated fatty acids was identified from depth species compared to the species collected from shallow water. The presence of a high concentration of a polymethyl-branched fatty acid, i.e., phytanic acid, and a demospongic acid (C26:2, Δ 5,9) were identified in both specimen, but the % composition of both acids were more in the species collected from depth than the species collected from shallow water. Important polyunsaturated fatty acids like 5,8,11,8,11,14, were also found in depth species which were absent in the species collected from shallow water. Antimicrobial screening of the lipid extracts of A. carteri was also studied against different pathogens.This work aims at extending knowledge on sponge lipids, especially for the genus Axinella (Dendy). Earlier bioactive alkaloids and cyclopeptides have been isolated from the tropical marine sponge Axinella carteri (Dendy) [1,2]. Previously bioactive pyrrole-derived alkaloids and triterpenes have been isolated from other Axinella sp. [3,4]. But much less work has been done in analyzing the fatty acid composition of these bioactive marine sponges. Differences in the lipid composition of the sponge from the two collection sites could have adaptive value. There are no investigations on the fatty acid composition of the A. carteri (Dendy) collected from the Bay of Bengal of the Orissa coast. We report here the total fatty acid composition of sponge species A. carteri (Dendy) collected from two different depths (13 m depth and 28 m depth) of the Bay of Bengal of the Orissa Coast. Antimicrobial screening of the lipid extracts of A. carteri was also studied against different pathogens.GC-MS analysis of the total lipid of the sponge A. carteri (Dendy) collected from two different depths of the Bay of Bengal of Orissa showed marked differences in their fatty acid composition (Table 1). The sponge species collected from 28 m depth contained a greater number of fatty acids when compared to the species collected from 13 m depth.The sponge species collected from 28 m depth is found to contain 58.94% of unsaturated fatty acids, which includes 52.87% of C26:2(5,9), a polyunsaturated fatty acid (PUFA), while the sponge collected from 13 m depth was found to contain 46.75% of unsaturated fatty acids, which includes 42.75% of C26:2(5,9). Important PUFAs such as C20:5(5,8,11,14,17) and C20:4(5,8,11,14) were present in the species collected from depth (0.43% and 2%, respectively), while these were not found in the species collected from shallow water. It was revealed that the % composition of saturated straight chain fatty acids was greater in sp. collected from shallow water (30.31%) when compared to the species collected from depth (6.42%), which is an important finding in...