Optimization, purification, and biochemical characterization of protease enzymes from Penicillium roqueforti using...

Proteases are industrially important enzymes widely used in food, textile, biotechnology and other industries and are produced using various microorganisms and substrates. In addition to carbon (carbohydrate) and/or nitrogen as primary nutrients, enzyme production requires additional supplements. Numerous studies have been done on using biobased and renewable resources as substrates for the production of enzymes. Sunflower meal is a major coproduct obtained during processing of the seed for oil and contains both proteins and carbohydrates which can provide the carbon and nitrogen necessary for enzyme production. However, biobased sources also contain protease inhibiting phenols, phytates, and antinutritional components which negatively impacts protease production and activity. Similarly, conditions during the production of the enzyme also affect yield and quality. Hence, it is necessary to develop optimum conditions and understand the influence of various nutrients and processing conditions on protease production. In this study, production of proteases was optimized using Penicillium roqueforti as the fungal source and sunflower meal as the substrate. Production conditions such as pH, time and temperature were optimized and the crude enzyme obtained was purified. Partially purified enzyme was studied for its activity under various pH, temperature and in the presence of promoters and inhibitors. Before purification, the enzyme showed highest activity of 17 International Units per milliliter (IU/mL) with alkaline pH being the most productive. Similarly, the purified enzyme had highest activity of 11 IU/mL and was found to be most active at 50 °C. Enzyme produced was classified as serene protease. Using sunflower meal may be an economical and commercially feasible approach for large scale production of proteases.