The pectin-degrading enzyme complex (PEDC) originates from the fungus Aspergillus niger and is used for fruit juice production, oil extraction from vegetables and citrus fruits as well as paper and pulp manufacture. Major drawbacks in the production of these enzymes include their cellular isolation, catabolic repression and an inefficient and costly recovery. The demand for the discovery of enzymes with novel properties led scientists of the EU-funded PGSYS EXCHANGE (Bioprocess Platform for the A. sojae PGzyme system) project to search for new sources. In addition, they developed and demonstrated novel bioprocessing routes to improve the production and function of these pectinases for industrial use. Researchers employed a non-genetically modified strain of Aspergillus sojae, which is a novel and safe source of food grade enzymes with unique properties. PEDC production was carried out utilising the so-called PG-system platform (PGSYS), a solid-state fermentation system that relies on agricultural by-products. In addition, they designed an alternative submerged fermentation system that generated pelleted mycelia and required a low power input during operation. Considerable effort went towards improving the downstream processing route for the recovery of the enzyme complex, and the characterisation of the crude enzyme mixture. The flexible biosynthesis platform yielded concentrates with distinct functional properties and high enzyme productivities. Overall, the PGSYS EXCHANGE platform for the production of food enzymes was a cost-effective and efficient alternative to existing systems. The ability to control the culture morphology was a further advantage for large-scale fermentations mostly applicable at industrial scale.
Pectinase, enzyme, PEDC, bioprocessing, Aspergillus sojae, PGSYS, fermentation