title: Bioremediation and lipid synthesis through mixotrophic algal consortia in municipal wastewater.
abstract: Algae grown in outdoor reactors (volume: 10 L and depth: 20 cm) were fed directly with filtered and sterilised municipal wastewater. The nutrient removal efficiencies were 86%, 90%, 89%, 70% and 76% for TOC, TN, NH4-N, TP and OP, respectively, and lipid content varied from 18% to 28.5% of dry algal biomass. Biomass productivity of ∼122 mg/l/d (surface productivity 24.4 g/m(2)/d) and lipid productivity of ∼32 mg/l/d were recorded. Gas chromatography and mass spectrometry (GC-MS) analyses of the fatty acid methyl esters (FAME) showed a higher content of desirable fatty acids (bearing biofuel properties) with major contributions from saturates such as palmitic acid [C16:0; ∼40%] and stearic acid [C18:0; ∼34%], followed by unsaturates such as oleic acid [C18:1(9); ∼10%] and linoleic acid [C18:2(9,12); ∼5%]. The decomposition of algal biomass and reactor residues with an exothermic heat content of 123.4 J/g provides the scope for further energy derivation.
authors.affiliation: Energy and Wetlands Research Group, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, India; Centre for Sustainable Technologies (astra), Indian Institute of Science, Bangalore 560012, India.
authors.forename: Durga Madhab
authors.initials: DM
authors.lastname: Mahapatra
authors.affiliation: Centre for Sustainable Technologies (astra), Indian Institute of Science, Bangalore 560012, India; Centre for infrastructure, Sustainable Transportation and Urban Planning [CiSTUP], Indian Institute of Science, Bangalore 560012, India.
authors.forename: H N
authors.initials: HN
authors.lastname: Chanakya
authors.affiliation: Energy and Wetlands Research Group, Centre for Ecological Sciences, Indian Institute of Science, Bangalore 560012, India; Centre for Sustainable Technologies (astra), Indian Institute of Science, Bangalore 560012, India; Centre for infrastructure, Sustainable Transportation and Urban Planning [CiSTUP], Indian Institute of Science, Bangalore 560012, India. Electronic address: cestvr@ces.iisc.ernet.in.
authors.forename: T V
authors.initials: TV
authors.lastname: Ramachandra
mesh_terms: D001673:Biodegradation, Environmental; D018533:Biomass; D002152:Calorimetry, Differential Scanning; D002244:Carbon / Q000032:analysis; D002947:Cities; D004952:Esters / Q000032:analysis; D005227:Fatty Acids / Q000032:analysis; D005427:Flocculation; D007194:India; D008055:Lipids / Q000096:biosynthesis*; D058086:Microalgae / Q000254:growth & development / Q000378:metabolism*; D059013:Microbial Consortia; D010758:Phosphorus / Q000032:analysis; D012722:Sewage / Q000737:chemistry; D013052:Spectrometry, X-Ray Emission; D017550:Spectroscopy, Fourier Transform Infrared; D062065:Wastewater / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification
chemical_list: D002244:Carbon; D004952:Esters; D005227:Fatty Acids; D008055:Lipids; D010758:Phosphorus; D012722:Sewage; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: GC–MS; Lipid; Mixotrophic algal consortia; SEM-EDXA; Wastewater treatment