Study of kinetic and optimization of the growth conditions of Kluyveromyces marxianus for the production of mannan bioemulsifier using cheese-whey powder

Mannan is a glycoprotein which consists of mannose polymers attached to the protein backbone that due to its natural amphiphilic compounds, it can be used as an effective bioemulsifier. Therefore, in this study, optimization and screening tests were conducted on the production of mannan from kluyveromyces marxianus using combinatorial method of the fractional of full factorial design and response surface together with determining the influence of the variables of lactose concentration based on whey powder, the concentration of yeast extract, enzyme activator and pH. It was revealed that the four variables of lactose and yeast concentration, pH and temperature had the most influence on the production of the mannan. The optimization of effective factors using response surface methodology demonstrated suitable conditions for mannan production with the maximum of 209.23 mg/100 ml with concentration level of 52.60 gr/l of the lactose, 10.38 yeast extract, pH of 5.36 and the temperature of 31.90°C with the maximum growth rate of 0.401 h-1. Results also showed that monod’s model had high correlation coefficient (0.998) and therefore could be used for prediction of yeast growth behavior as well as mannan production.