10.22376/ijpbs.2019.10.1.p1-12 Volume 3 Issue 3 2012 (July - September) Lipid productivity is a critical variable for evaluating algal species for biodiesel production. The pennate diatom lessThan i greaterThan Nitzschia closterium lessThan /i greaterThan (W. Sm.) isolated from the local water body of Madurai was cultivated in four different media (WCg, Csi, F/2 and Diatom medium) and screened for the presence of neutral lipid content using Nile red fluorescent dye. The relative abundance of lipid content was estimated by fluorescence spectroscopy using Nile red. lessThan i greaterThan The numbers of cells exhibiting fluorescence were found to increase on 10 lessThan sup greaterThan th lessThan /sup greaterThan day in comparison to 5 lessThan sup greaterThan th lessThan /sup greaterThan day in the strain lessThan /i greaterThan lessThan i greaterThan Nitzschia closterium lessThan /i greaterThan lessThan i greaterThan . lessThan /i greaterThan The maximum lipid production was noticed in lessThan i greaterThan Nitzschia closterium lessThan /i greaterThan grown at pH -7. Green and orange color bands developed in the thin layer chromatography indicated the presence of chlorophyll a and fucoxanthin pigments. Thin Layer Chromatography of the extracted lipid fractions revealed the presence of Monoacylglycerols, Diacylglycerols and Triacylglycerols. Gas Chromatography confirmed the presence of fatty acids such as Myristic (14:0), Palmitic (16:0), Stearic (18:0) and other FAMES in the isolated strain. In addition, high molecular weight hydrocarbons were detected using GC-MS analysis. The higher percentage of lipid and fatty acids indicate the suitability of this indigenous organism as a potential source for algal bio-fuel. R.Sugapriya, S.Srisudha And P. Gunasekaran Nitzschia closterium, Lipid, Hydrocarbons, Fatty acids, GC, GC-MS. 545-554