title: A novel process for enhancing oil production in algae biorefineries through bioconversion of solid by-products.
abstract: This paper focuses on a novel process for adding value to algae residue. In current processes oleaginous microalgae are grown and harvested for lipid production leaving a lipid-free algae residue. The process described here includes conversion of the carbohydrate fraction into glucose prior to lipid extraction. This can be fermented to produce up to 15% additional lipids using another oleaginous microorganism. It was found that in situ enzymes can hydrolyze storage carbohydrates in the algae into glucose and that a temperature of 55 °C for about 20 h gave the best glucose yield. Up to 75% of available carbohydrates were converted to a generic fermentation feedstock containing 73 g/L glucose. The bioconversion step was found to increase the free water content by 60% and it was found that when the bioconversion was carried out prior to the extraction step, it improved the solvent extractability of lipids from the algae.
authors.affiliation: Satake Centre for Grain Process Engineering, School of Chemical Engineering and Analytical Science, Manchester University, Oxford Road, Manchester M13 9PL, United Kingdom. antoinetrzcinski@hotmail.com
authors.forename: Antoine P
authors.initials: AP
authors.lastname: Trzcinski
authors.forename: Ernesto
authors.initials: E
authors.lastname: Hernandez
authors.forename: Colin
authors.initials: C
authors.lastname: Webb
mesh_terms: D061249:Batch Cell Culture Techniques; D056804:Biofuels / Q000032:analysis*; D001709:Biotechnology / Q000295:instrumentation / Q000379:methods*; D002241:Carbohydrates / Q000032:analysis; D005947:Glucose / Q000096:biosynthesis; D007700:Kinetics; D008055:Lipids / Q000032:analysis; D058086:Microalgae / Q000254:growth & development / Q000378:metabolism*; D009584:Nitrogen / Q000032:analysis; D009821:Oils / Q000378:metabolism*; D012212:Rheology; D054712:Salinity; D013696:Temperature; D014783:Viscosity
chemical_list: D056804:Biofuels; D002241:Carbohydrates; D008055:Lipids; D009821:Oils; D005947:Glucose; D009584:Nitrogen