title: Microbial conversion of synthetic and food waste-derived volatile fatty acids to lipids.
abstract: Lipid accumulation in the oleaginous yeast Cryptococcus albidus was evaluated using mixtures of volatile fatty acids (VFA) as substrates. In general, batch growth under nitrogen limitation led to higher lipid accumulation using synthetic VFA. During batch growth, an initial COD:N ratio of 25:1mg COD:mg N led to maximum intracellular lipid accumulation (28.3 ± 0.7% g/g dry cell weight), which is the maximum reported for C. albidus using VFA as the carbon source, without compromising growth kinetics. At this feed COD:N ratio, chemostat cultures fed with synthetic VFA yielded statistically similar intracellular lipid content as batch cultures (29.9 ± 1.9%, g/g). However, batch cultures fed with VFA produced from the fermentation of food waste, yielded a lower lipid content (14.9 ± 0.1%, g/g). The lipid composition obtained with synthetic and food-waste-derived VFA was similar to commercial biodiesel feedstock. We therefore demonstrate the feasibility of linking biochemical waste treatment and biofuel production using VFA as key intermediates.
authors.affiliation: Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, United States.
authors.forename: Shashwat
authors.initials: S
authors.lastname: Vajpeyi
authors.affiliation: Department of Earth and Environmental Engineering, Columbia University, New York, NY 10027, United States. Electronic address: kc2288@columbia.edu.
authors.forename: Kartik
authors.initials: K
authors.lastname: Chandran
mesh_terms: D000085:Acetates; D000693:Anaerobiosis; D056804:Biofuels; D057919:Biological Oxygen Demand Analysis; D018533:Biomass; D002176:Candida albicans / Q000378:metabolism*; D002244:Carbon / Q000737:chemistry; D003454:Cryptococcus / Q000378:metabolism; D005232:Fatty Acids, Volatile / Q000737:chemistry*; D005285:Fermentation; D005502:Food; D005522:Food Services; D005735:Garbage; D031286:Jatropha; D007700:Kinetics; D008055:Lipids / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry; D012037:Refuse Disposal / Q000379:methods; D012722:Sewage / Q000737:chemistry; D013025:Glycine max; D014865:Waste Disposal, Fluid
chemical_list: D000085:Acetates; D056804:Biofuels; D005232:Fatty Acids, Volatile; D008055:Lipids; D012722:Sewage; D002244:Carbon; D009584:Nitrogen
keywords: Biodiesel; Biofuel; Fermentation; Microbial lipids; Volatile fatty acids