143 STUDIES ON BIOMASS OF DIFFERENT SCENEDESMUS, etc ..... al., 2010). In this respect, (Chisti, 2007) re- ported that only microalgae represent a relia- ble renewable source of biodiesel that main- tains the potential to completely to displace fossil diesel. Accumulating research outcomes (e.g Hu et al., 2008; Mandal and Mallick 2009; Ho et INTRODUCTION INTRODUCTION Microalgae are very efficient light energy driven cell factories capable of metabolizing carbon dioxide, with almost zero level of ener- gy, to highly energetic metabolites including long chain- fatty acids that compose the feed- stock of biodiesel (Spolaore et al., 2006; Chisti 2007; Brennan and Owenede 2010; Mata et STUDIES ON BIOMASS OF DIFFERENT STUDIES ON BIOMASS OF DIFFERENT SCENEDESMUS SCENEDESMUS SPECIES AS FEASIBLE FEEDSTOCK OF BIODIESEL SPECIES AS FEASIBLE FEEDSTOCK OF BIODIESEL Mohammed I. Abdel-Hamid Mohammed I. Abdel-Hamid * , (1) (1) ; Samah A. Salama ; Samah A. Salama (1) (1) ; Yehia A. Azab ; Yehia A. Azab (1) (1) ; Mervat H. Hussein Mervat H. Hussein (1) (1) ; Eman I. Abdel-Aal Eman I. Abdel-Aal (2) (2) (1) Botany Department, Faculty of Science, University of Mansoura, Mansoura, Egypt, (2) Hydrobiology Laboratory, Inland waters and aquaculture branch, National Institute of Oceanography and Fisheries, El Serw Research Station, Damietta, Egypt. ABSTRACT ABSTRACT Biodiesel from microalgae seems to be promising renewable biofuel. Several publications have indicated high potential of Scenedesmus species for biodiesel production. Four different Scene- desmus species namely Scenedesmus quadricauda var. maximum (Isolate BIRD-CHL190), Scenedesmus parisiensis (Isolate BIRD-CHL193), Scenedesmus abundans var. bervicauda (Iso- late BIRD-CHL194) and Scenedesmus quadricauda var. quadrispina (Isolate BIRD-CHL197), were isolated from freshwater samples collected from the Delta region of the River Nile in Egypt . Growth rates and lipid content of different Scenedesmus isolates were investigated. Lipids were extacted by dichloromethane solvent. Lipids were subjected to base and acid catalyzed transes- terificaion to produce fatty acids methyl esters (FAMEs biodiesel). FAMEs were qualitatively and quantitatively analyzed using GC/MS analysis. Different Scenedesmus isolates maintained marked differences in biomass production, growth rates, lipid contents and FAMEs. Dry weight biomass of 30 day cultured ranged between 0.378 gl -1 (BIRD-CHL190) and 0.42gl -1 (BIRD- CHL197). Growth rates fluctuated within a narrow range between 0.225 Dd -1 (BIRD-CHL190) and 0.29 Dd -1 (BIRD-CHL197). The wt% of lipids ranged between 5.64% (BIRD-CHL 194) and 7.575% (BIRD-CHL190). FAMEs (wt%) ranged between 0.42% (BIRD-CHL197) and 23.66% (BIRD-CHL190). Based on experimental results, the biomass of Scenedesmus quadricauda var. maximum seems promising feedstock for feasible production of biodiesel. Key words : Key words : algae, lipids, Scenedesmus, biodiesel. Journal of Environmental Sciences, 2015; Vol. 44, No. 1 : 143-160