Inulin hydrolysis by kluyveromyces marxianus inulase produced on some agricultural wastes

High fructose syrup is produced by the action of inulase on inulin. Many yeast strains were used in this study for inulase production on some agricultural wastes. Results showed that Kluyveromyces marxianus was the most potential strain in inulase production among sixteen yeast strains. K. lactis and K. fragilis were found in the second order. 15 min. was chosen as the best reaction time. PH 5.5 and 6.0 was found as the optimum pH for K. lactis and K. fragilis and K. marxianus, respectively. Enzyme activity was maximal at 35C. K. marxianus inulase was maximized after 3 days of incubation and pH 7.5 at 30C. Biological wastes played an important role in K. marxianus inulase production. Dahlia tubers were the best carbon source for inulase synthesis. Also, chicory roots, orange peel and beet pulp gave high amount of inulase compared to other carbon sources. Ammonium nitrate induced inulase production by K. marxianus which was found as the best nitrogen source between all inorganic and organic ones. The degree of inulin hydrolysis reached 76.50% after 2 hr with 40 units of enzyme in 5% inulin solution. This revealed the importance of this enzyme in the production of fructose syrup from inulin; that industry is very important from healthy and economic viewpoints