Fermentation was carried out in a stirred tank 15 L bioreactor (working volume: 10 L, Biogenie, Quebec, Canada) equipped with accessories and programmable logic control (PLC) system for dissolved oxygen (DO), pH, anti-foam, impeller speed, aeration rate and temperature. The software (iFix 3.5, Intellution, USA) allowed automatic set-point control and integration of all parameters via PLC.