Response Surface Methodology-Based optimization of Inulinase Production from New Bacillus Isolates

Abstract

This study aimed to investigate new bacterial sources with the ability to produce inulinase and to optimize fermentation conditions for inulinase production. The inulinase production was carried out using newly isolated Bacillus licheniformis and Bacillus velezensis among identified sixteen bacterial strains. The four essential variables incubation time (1-3 days), temperature (25-40°C), pH (5-7), and Wheat Bran (WB) level (1-5%) determined by the Plackett-Burman design (PB) were selected for optimization studies with Box-Benhken Design (BBD). These parameters were found to be very effective on inulinase production. The maximum inulinase activities for B. licheniformis and B. velezensis were 401.18 EU/mL and 344.61 EU/mL. Both inulinases sustained 50% of their initial activity at 30°C for 9 days. The results point out that bacteria are an important source as inulinase producer. The new isolates can be used in production of inulinase for industrial processes.