Production of extracellular proteases by Mucor circinelloides using D-glucose as carbon source / substrate

Abstract

Recently, some Mucorales species have been reported as protease producers. The production of extracellular proteases by Mucor circinelloides using glucose as substrate was studied. Experiments were carried out with different D-glucose concentrations (40, 60 and 80 g/L). Biomass, pH and protease activity were determined. Although biomass production had reached best yields for the medium containing D-glucose in a concentration of 80 g/L, the enzymatic production was higher when the substrate concentration was reduced to 40 g/L. The yield factor for product on cell growth and the yield factor for product on carbon substrate were higher when the microorganism grew in medium containing 40 g/L glucose. The kinetics parameters suggest that this strain seems to be promising as an alternative microorganism for protease production.

Cryptococcus neoformans var. grubii isolates recovered from persons with AIDS demonstrate a wide range of virulence during murine meningoencephalitis that correlates with the expression of certain virulence factors

“…Protein concentration was measured by reference to a standard curve. Extracellular proteinase activity was measured as previously described (Andrade et al, 2002;Leighton et al, 1973). Units of proteolytic activity were expressed as mg azoalbumin hydrolysed per hour.…”

Aspartic proteinases from Mucor spp. in cheese manufacturing

“…and (b) rennin-like enzymes produced by Mucor spp. (Fraile et al 1981;Venera et al 1997;Fernandez-Lahore et al 1999;Neelakantan et al 1999;Andrade et al 2002;Machalinski et al 2006), Rhizomucor spp. (Thakur et al 1990;Escobar and Barnett 1993;Silveira et al 2005;De Lima et al 2008), and Endothia parasitica (Sardinas 1968).…”

“…strains (Belyauskaite et al 1980;Fraile et al 1981;Handel and Fraile 1984;Fernandez-Lahore et al 1998;Andrade et al 2002). Fraile et al (1978) performed a pioneering study on the ability of Mucor spp.…”

“…A common observation is that while simple substrates, such as casein and gelatin, yield low enzyme activity units, more complex substrates, such as soybean meal and wheat bran, result in higher proteinase activities (Boer and Peralta 1999;Sumantha et al 2006). On the other hand, it has been frequently described that, in a defined medium, a protein source must be present for the enzyme to be produced (Andrade et al 2002). M. mucedo is unique among other Mucor spp.…”

“…Additional information can be gathered from Andrade et al (2002), who studied the production of extracellular proteinases from M. circinelloides using different concentrations of D-glucose (40, 60, and 80 g/l) as a substrate. Although highest biomass production was obtained in a medium containing D-glucose at a concentration of 80 g/l, the maximum enzyme production was found when the substrate concentration was reduced to 40 g/l.…”