Study of the growth of two yeast strains (Yarrowia lipolytica and Pichia guilliermondii) in an ammonium formate solution of rubber effluents

Abstract The growth of microorganisms is influenced by several physico-chemical parameters that need to be controlled before starting a biological treatment plant for better process efficiency. In this study, the influence of temperature (25-40 °C), pH (4-8), and ammonium formate concentration (1.59-7.94 mM) on the growth of two yeast strains (Y.lipolytica and P.guilliermondii ) examined in a batch process. Temperature has a direct impact on the kinetic growth parameters with an activation energy (Ea) of 14.3 kcal/mol and R2 0.95 for Y.lipolytica and 12.5 kcal/mol and R2 0.97 for P.guilliermondii, what indicating a dominant biological regime. The yeast strains are acidophilic with a maximum growth pH between pH 5 and 6.