Bacterial polygalacturonase production using apple pomace by submerged fermentation

Özışık, Berfin
Over the past decade, there has been a growing interest in the waste management sector, primarily due to the increasing environmental threat posed by waste disposal. Scientific research in recent years has focused on finding solutions to this issue by processing agricultural lignocellulosic residues into valuable products. Industries across various sectors, including but not limited to food production, heavily rely on enzymes. Nevertheless, the high cost of producing enzymes at an industrial scale remains a notable obstacle. As a result, there is a rising inclination towards using lignocellulosic materials to produce enzymes, with the aim of both cost reduction and minimizing environmental impact. In this study, it was aimed to enhance polygalacturonase (PGase) production using apple pomace by fed-batch submerged fermentation. Bacillus subtilis NRRL B-4219 was employed as PGase producer and all fermentation experiments were carried out at 30 oC and 130 rpm. Box-Behnken experimental design of Response Surface Methodology was used for optimization of parameters, namely additional substrate amount, addition time, and fermentation period. The highest result (12.27 U/mL) was obtained when the fermentation lasted three days and 1 g/L pectin was added at the second day of fermentation. Analysis of the results revealed optimum process to be with no additional substrate and three days of fermentation; however, the results support addition of 1 g/L pectin on day 2. Overall, the present study proves apple pomace as a cost-effective alternative for bacterial PGase production.
Citation Formats
B. Özışık, “Bacterial polygalacturonase production using apple pomace by submerged fermentation,” M.S. - Master of Science, Middle East Technical University, 2023.