Abstract
This study aimed to identify and characterize a pectinase-producing novel yeast from the fermented juice of Phyllanthus emblica and apply the enzyme for fruit juice clarification. Among the five pectinase-producing yeasts, isolate-1 exhibited the highest pectinase activity and was further used in this study. Based on morphological, physiological, and 18SrRNAanalyses, isolate-1 was recognized as a new strain sharing 99% sequence homology with other Meyerozyma strains and was thus designated as Meyerozyma sp. VITPCT75. The strain produced pectinase optimally at a temperature and pH of 25oC and 7, respectively. Maximum pectinase production was observed after 4-days incubation. The enzyme exhibited optimum activity at the temperature of 25 °C and pH 7.0. The enzyme was more stable at a temperature and pH of 20 °C and 7, respectively. Storage stability studies revealed that the enzyme was stable at -20 °C. The cell-free supernatant was partially purified using ammonium sulfate and solvent precipitation. Acetone at a concentration of 20% assured an adequate partial purification. The molecular weight of pectinase was determined as 6 kDa. The enzymatic metal ion preference-related studies revealed that Ca²z, Kz, Cu²z, Fe²z, and Ba²z ions enhanced, Ni²z ions moderately inhibited, and Mn²z ions intensely inhibited the enzymatic activity. Neither Na+ and Mg2+ ions nor EDTA affected the enzyme activity. When subjected to fruit juice clarification, the enzyme significantly reduced the viscosity of the juice.
Publisher
Journal of Pure and Applied Microbiology
Subject
Applied Microbiology and Biotechnology,Microbiology,Biotechnology