Inulinase Production by Penicillium citrinum ESS in Submerged and Solid-State Cultures

Problem statement: This work reports the Penicillium citrinum ESS strain as a new source of inulinase (2,1-β-D fructanhydrolase, E.C. 3.2.1.7). Approach: The enzyme was produced in both, Solid-State (SSC) and Submerged Culture (SmC) using a basal medium added either with inulin or sucrose (5 gL^-1). Results: The culture grew faster in SmC than in SSC with both carbon sources; however, yields of inulinase activity per gram of biomass were higher in SSC (1,658,237.28 for inulin and 66598.96 for sucrose) than in SmC (441.05 for inulin and 183.91 for sucrose). Conclusion: The highest inulinase production was obtained by SSC, either with inulin or sucrose, reaching values of 6650 and 2970 U/L respectively. In contrast, in SmC were obtained higher levels of inulinase activity (2241 U/L) with sucrose as carbon source (24 h), while with inulin, the enzyme production was negatively affected and retarded.