Production of extracellular aspartic protease in submerged fermentation with Mucor mucedo DSM 809

WOS: 000282232900021Fungal milk-clotting enzymes have gained value as bovine Chymosin substitutes in the cheese industry. In this work, the effects of culture conditions on the production of extracellular milk clotting enzymes from Mucor mucedo DSM 809 in submerged fermentation were studied. The maximum activity was observed after 48 h of cultivation at 24 degrees C in Erlenmeyer flasks. The optimized initial pH and shaking speed for enzyme production were 4.5 and 220 rpm, respectively. Glucose at a concentration of 1% (w/ v) was the best carbon source for the production of enzyme among the carbohydrates examined (glucose, fructose, lactose, maltodextrin). On the other hand casein at a concentration of 0.5% (w/v) was the selected nitrogen source in the media formulation. Under optimized conditions enzyme levels reached 130 SU per ml fermentation broth. The inoculum type and size has also affected biomass production and the biosynthesis of the enzyme. The preferred method was the inoculation of the culture media with spores at a total load of 6x10(5) spores per flask.BMBF-ERA-NetFederal Ministry of Education & Research (BMBF); Euro TransBio-3; [BIO-010103441508]; [JUB 5130-50290]This work was supported by BMBF-ERA-Net, euro TransBio-3, BIO-010103441508 (JUB 5130-50290)

Aspartic proteinases from Mucor spp. in cheese manufacturing

WOS: 000287143600008PubMed ID: 21127856Filamentous fungi belonging to the order of Mucorales are well known as producers of aspartic proteinases depicting milk-clotting activity. The biosynthesis level, the biochemical characteristics, and the technological properties of the resulting proteinases are affected by the producer strain and the mode of cultivation. While the milk-clotting enzymes produced by the Rhizomucor spp. have been extensively studied in the past, much less is known on the properties and potential applications of the aspartic proteinases obtained for Mucor spp. Indeed, several Mucor spp. strains have been reported as a potential source of milk-clotting enzymes having unique technological properties. Both submerged fermentation and solid substrate cultivation are proven alternatives for the production of Mucor spp. aspartic proteinases. This review provides an overview on the bioprocessing routes to obtain large amounts of these enzymes, on their structural characteristics as related to their functional properties, and on their industrial applications with focus on cheese manufacturing