Use of carob extract as carbon resources in the production of inulinase enzyme

Inulin is one of the plant-derived polysaccharides containing glucose and fructose in its structure. Enzymes are protein-based substances that are formed by living cells and have the ability to specifically catalyze chemical reactions. Inulinases are inulin-specific enzymes that hydrolyze inülin. The inulinases found in some microorganisms are classified as endo-inulinase and exo-inulinase according to the breakdown of inulin. Inulinases are produced by Aspergillus niger, are exocrine type of inulin hydrolases. Inulinases have a significant share in the food industry and its use in other areas. Carob fruit grows in Turkey in natural areas of the Mediterranean coastline. The sugar content, of the fruit which is widely used in many industrial fields, is highly suitable for usage as a substrate in biotechnology. In this project, the potential use of carob fruit extract as an alternative carbon source in inulinase enzyme production has been investigated. In this study, carob bean extract, which was any used in the production of inulinase enzyme, was used as a carbon source. 12 different media were formulated with Plackett-Burman and fermentations were carried out with 7 different variables added separately at different ratios to the carob extract. Optimum nutrient composition determined for maximum inulinase activity was 5° Bx carob extract with 1% yeast extract. Subsequently, optimum fermentation operating conditions with CYM (Response Surface Method) were determined as 250 rpm agitation speed, 2.3% inoculation amount and 135 mL media volume. The maximum activity of the fermentations recommended with CYM was 1646.05 U / mL. As a result of validation experiments performed under the optimized fermentation conditions with Design Expert program, 1560.17 U / mL was the maximum enzyme activity reached. Partial purification with enzyme preparatory ultrafiltration obtained by fermentation was carried out through filters with a separation limit of 10, 30, 50 kDa. As a result of the UF treatment, 6133.72 U / mL inulinase was detected in the 50 kDa retentate, 6278.69 U / mL in 30 kDa and 6343.26 U / mL inulinase activity in 10 kDa. Thus, the enzyme activity was increased about 4.5 times by the UF process. The results have shown that the carob extract can be used as a good carbon source for the production of inulinase enzyme. In addition, was to be reached in this study an enzyme production model integrity from raw material to product.