Microbial lipids and added value metabolites production by Yarrowia lipolytica from pork lard

Yarrowia lipolytica is a suitable microbial platform to convert low-value hydrophobic substrates into microbial oils and other important metabolites. In this work, this yeast species was used to simultaneously synthetize ex novo lipids and produce citric acid and lipase from animal fat (pork lard) adding higher value to the low-cost fatty substrate. The effect of pH, lard concentration, arabic gum concentration and oxygen mass transfer rate (OTR) on lipids accumulation on Y. lipolytica batch cultures was assessed by an experimental design based on Taguchi method. OTR was by far the most influential parameter in the range of 96 mg L1 h1 to 480 mg L1 h1. A bio-modification of initial lipidic substrate was observed and, depending on the nutritional and operational conditions, specialty lipids with specific composition and high added-value were obtained. The unsaturated-to-saturated fatty acids ratio of these microbial lipids is higher than in initial substrate, which indicates that they are more suitable than animal fat for food additives. Moreover, the simultaneous induction of lipase and citric acid by Y. lipolytica growing in animal fat demonstrate that a biorefinery approach may be designed based on animal fat raw material.This work was financially supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the project TÜBITAK 2014 (TUBITAK/0009/2014) and of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145FEDER-006684), Post-Doctoral grant (SFRH/BPD/101034/2014) attributed to Marlene Lopes and BioTecNorte operation (NORTE-010145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 – Programa Operacional Regional do Norte.