Effect of Various Parameters on Pectinase Producing Activity of Two Bacterial Isolates and Application of Crude Enzyme in Apple Juice Extraction

Two pectinase producing bacterial strains were isolated from decayed oranges and tomato. Preliminary identification of two potential isolates was carried out by Grams staining and biochemical tests. Based on Grams staining and microscopic examination, two bacterial strains, O6 and T2, are Gram positive Cocci shaped bacteria. Both strains showed different pectinolytic zones depending on the concentration of inoculum and the larger pectinolytic zones were observed by O6. The investigation of optimum crude enzymes producing activity of isolated strains was done at different temperature, pH, reaction time and substrate concentration. The best enzyme activity was observed at seven days incubation period and it was found that the optimum reaction temperature were 40C and 45C for isolate O6 and T2 respectively. Both two isolates showed maximum activity at pH 5 and the optimum reaction time at 35mins as well. The optimum pectinase producing activity of isolate o6 and T2 occur at 1 % pectin and then remain constant for higher than 1 %. The highest protein content of the cell free supernatant was found that the isolate O6 is 0.514 mg/ml followed by T2 which is 0.453 mg/ml. Between two bacterial isolates, O6 showed better pectinase activity than T2 at all optimum conditions except reaction temperature.