Inulinase production by Geotrichum candidum using Jerusalem artichoke as sole carbon source

Inulinase is a versatile enzyme used in many fields, especially in food industr, to produce high fructose syrups. Jerusalem artichoke (JA) (Helianthus tuberosus L.) has a high inulin storage capacity. In the present study, inulinase production by Geotrichum candidum was achieved using JA as a sole and cheaper carbon source, when compared with traditionally used substrates like pure inulin and sucrose. The current study was carried out in two parts. Firstly, ten strains of G. candidum were isolated from different samples and screened for high inulinase production. In the second part of the study, fermentation conditions such as JA concentration, initial pH, cultivation temperature, agitation speed and incubation time were tested in order to optimise inulinase activity. The results showed that maximum inulinase activity was obtained as 45.62 U/ml in optimised fermentation medium using 3.0% (w/v) of JA. Consequently, JA has a potential as an effective and economical substrate for inulinase production.