The culture or co-culture of Candida rugosa and Yarrowia lipolytica strain rM-4A, or incubation with their crude extracellular lipase and laccase preparations, for the biodegradation of palm oil mill wastewater

Wastewater generated by the palm oil industry contains a high concentration of oil, grease and phenolic compounds, which makes it difficult to treat. The aim of this research was to evaluate the ability of free Candida rugosa and Yarrowia lipolytica rM-4A yeast cell cultures, as a single yeast strain and as a co culture, as well as their crude extracellular enzyme preparations, to reduce the total phenolic compounds, triglycerides and chemical oxygen demand (COD) level in palm oil mill effluent (POME) that contains high amounts total phenolic compounds (9783 mg L-1) and oil and grease (7762 mg L-1). Culture with Y lipolytica rM-4A effectively reduced the total phenolic content in undiluted POME, resulting in removal of 36% of the total phenolic content after 96 h. The highest removal of triglyceride (98.5%) and COD (60.3%) were observed in undiluted POME treated by the co-culture of C rugosa and Y lipolytica for 120 h. Triglyceride was removed rapidly by the extracellular lipase produced by C rugosa, reaching 93% degradation after 48 h. This research revealed the excellent potential of both crude extracellular enzyme preparations and the co-culture of the two yeasts in the pretreatment of high fat and oil containing POME. (C) 2017 Elsevier Ltd. All rights reserved.