Alpha Amylase Production by Bacillus Licheniformis from Agricultural Waste: Effect of C: N Ratio and Different Carbon and Nitrogen Sources

Alpha Amylase Production by Bacillus Licheniformis from Agricultural Waste: Effect of C: N Ratio and Different Carbon and Nitrogen Sources

Background and aim: Use of enzymes for industrial processing has received considerable attention in recent years. Amylases are one of the main enzymes used in industry. Amylases have potential application in a wide number of industrial processes such as food, fermentation and pharmaceutical industries. Alpha amylase, is an enzyme that hydrolyses alpha bonds of large, alpha-linked polysaccharides, such as starch and glycogen, yielding glucose and maltose. The aim of this study was to investigate the effect of C: N ratio and different carbon and nitrogen sources on alpha amylase production by bacillus licheniformis from agricultural waste. Methods: Bacillus Licheniformis PTCC 1525 was obtained from the Iranian Research Organization for Science and Technology (IROST). In this work, design of experiments (DOE) methodology using full factorial design was applied to evaluate the influence of C:N ratios (1, 10, 20, 30), different carbon sources (corn, rice and potato waste) and different nitrogen sources (ammonium sulfate, ammonium nitrate, urea, yeast extract, peptone, casein) on alpha amylase production. The fermentation process was held at a temperature of 37 °C for 48 hours. Measurement of the enzyme activity was carried out by measuring optical density at 546 nm. Result: The highest alpha amylase activity (380.67 U/ml) was achieved at C:N ratio of 30:1, corn waste as carbon source and ammonium sulfate as nitrogen source. Conclusion: The results of this study showed that corn waste due to natural sources of protein and high starch content is a good and cost-effective substrate for alpha amylase production.