Extracellular pectinase production from a novel Yarrowia phangngaensis XB3 grown on banana waste and its application in fruit juice clarification

Abstract

Pectinases are important enzymes used in several industries, including food and beverage. Yarrowia phangngaensis, a yeast with pectinase-producing potentials, was investigated for its ability to produce copious pectinase using agro-wastes as substrates. Culture optimization studies were conducted, followed by partial purification by ethanol precipitation and application in apple juice clarification. The optimum pH and temperature for the pectinase activity were studied, and the suitable parameters for apple juice clarification were determined. Culture optimization remarkably influenced pectinase production by Yarrowia phangngaensis. Banana peels elicited the highest pectinase production compared to potato, pawpaw, orange and lemon peels. Yeast extract and ammonium sulphate proved best for pectinase synthesis. The optimum condition for pectinase production was 5% banana peel, pH 7.5, 1.4 × 104 cells ml−1 and incubation for 36 h. Culture optimization increased the pectinase yield by 182%. Ethanol precipitation (50%) resulted in a 5.31-fold increase in the specific activity of the pectinase. The optimum juice clarification was achieved by treating 10 ml apple juice with 7.03 IU ml−1 pectinase for 120 min. The turbidity and clarity reduction percentages were 39.33% and 59.84%, respectively. The pectinase from Yarrowia phangngaensis is applicable in food and other industries.