Available online at www.scholarsresearchlibrary.com Scholars Research Library Archives of Applied Science Research, 2014, 6 (1):131-138 (http://scholarsresearchlibrary.com/archive.html) ISSN 0975-508X CODEN (USA) AASRC9 131 Scholars Research Library Growing of Chlorella, Scenedesmus and Botryococus in sewage water for biodiesel production Sirangala T. Girisha*, Krishnappa Ravikumar, Venkatachalapathy Girish and Bangalore R. Mrunalini Department of Microbiology and Biotechnology, Jnanabharathi Campus, Bangalore University, Bangalore _____________________________________________________________________________________________ ABSTRACT Algae grown on wastewater media are a potential source of low-cost lipids for production of liquid biofuels. This study was aimed to estimate the effect of Physico-chemical characteristics of normal and sewage water (pH 7.60 and 6.60, EC 15.97and 12.36 µmol, free Co 2 1.48 and 0.74 , nitrogen 0.90 and 0.50 mg/l, potassium 168.11 and 54.63 mg/l, calcium 249.52 and 112.21mg/l, magnesium 104.91 and 51.19 mg/l, sulphate 57.08 and 28.35 mg/l, chloride 98.00 and 84.63 mg/l, carbonates 362.18 and 32.64 mg/l and bicarbonates 1138.30 and 253.33mg/l in sewage and normal water respectively) on Chlorella, Scenedesmus and Botryococus. The highest biomass (4.533 mg ml -1 ), chlorophyll (15.56 μg ml -1 ), lipid (49 %), acid value (0.52mg KOH/g), density (0.885 g/cm 3 ), iodine value (75 mg/g), saponification value (0.125mg KOH/g), viscosity (4.8mm 2 /sec), myristic acid (9.0%), oleic acid (9.3%), linolenic acid (20.1%), palmitic acid (35.3%), stearic acid (6.1%) was observed in Scenedesmus than Botryococus and Chlorella. The properties of algal oil meet all the properties given by American society for testing and materials (ASTM) D6751, ISO 15607and EN14214- Europe. Hence, it is concluded that algae can be grown better in sewage water than normal water for their oil and used as a potential feedstock for liquid biofuel production. Key words: Chlorella, Scenedesmus, Botryococus, sewage water, biodiesel _____________________________________________________________________________________________ INTRODUCTION Biofuels produced from plants have potential to replace a significant fraction of our fossil fuel needs with a renewable alternative [1] and it is believed that large-scale production of biodiesel from edible oils may bring global imbalance to the food supply. Hence, environmentalists started to debate on negative impact of biodiesel production from edible oil [2]. However, concern has grown that use of food crops for production of ethanol, biodiesel or other renewable fuels will increase food prices while having little impact on greenhouse gas emissions [3]. Hence, as a solution for competition with food versus fuel crisis, non-edible vegetable oils are found to be suitable for biodiesel production under experimental conditions [4]. US Department of Energy suggested that algae are capable of producing oil suitable for conversion to biodiesel with an aerial productivity of 20-40 times that of oilseed crops [5]. Use of fresh water for microalgae cultivation has generated great debate. Further, use of conventional media in the form of mineral salts is uneconomical. Use of algae for sewage wastewater treatment in ponds is well established [6] and algae-based treatment of dairy and