INFLUENCE OF GLUCOSE AND L-ASPARAGINE CONCENTRATIONS ON L-ASPARAGINASE PRODUCTION BY ENDOPHYTIC FUNGI

Abstract

In this study, five L-asparaginase–producing endophytes (ODL4, PBS1, PBL13, CCL1, MKS1) were evaluated for their L-asparaginase production when cultivated in various glucose (0, 0.5, 1, 2, 3, 4, 5 %) and L-asparagine (0, 5, 10, 20, 30, 40, 50 mM) concentrations over a period of 20 days. L-asparaginase production was quantified via Nesslerization and expressed as L-asparaginase activities. Results revealed supplementation with nitrogen-source (L-asparagine) induced higher L-asparaginase activities compared to carbon-source (glucose), with means of 0.106 compared to 0.062 µM mL-1 min-1, respectively. The optimum concentration of L-asparagine was 30 mM. On the contrary, optimum levels for glucose was inconclusive. Among the isolates, isolate MKS1 produced the highest L-asparaginase activities when supplemented with 5% glucose and 10 mM asparagine. This study revealed that nitrogen-based source (L-asparagine) is more effective than carbon-source (glucose) in inducing L-asparaginase activities.