Faheema, C., Smitha, K.V., Sooraj S. Nath and Kunhi, A.A.M. (2016) Production and partial characterization of a raw starch hydrolyzing enzyme from Aspergillus carbonarius S-CSR-0002. Res. J. Pharm. Biol. Chem. Sci., 7(6) 2016: 2224-2236.

 

 ABSTRACT 

Conversion of raw starch by amylase is important in a way that some of the products could be used as industrial raw materials for value added products. This will reduce wastage and improve economic gain. This study was performed to isolate raw starch digesting microorganism from soil. This begins with the sample collection screened for amylase producers by observing the halo zone appeared around the colonies. Microorganism was characterized by saline wet mount and LPCB staining technique was Aspergillus carbonarius S-CSR-0002, gave the amylase yield (880 U/ml) in submerged fermentation process. Amylase from Aspergillus carbonarius S-CSR-0002, a fungus isolated from soil contaminated with canteen kitchen waste showed an ability to degrade tapioca, corn, arrow root, rice starches. Tapioca has the highest degree of hydrolysis followed by corn, rice, arrow root, consecutively. The crude amylase preparation had temperature and pH optimal activities at 30 °C and 7.0 respectively, optimal stabilities at 30 °C and 7.5 respectively. The optimum substrate concentration was 5%. The highest adsorption of crude enzyme was found with rice starch followed by arrow root, corn and tapioca. Crude enzyme was partially purified by 20-100% ammonium sulphate precipitation followed by dialysis, in which maximum amylolytic activity shown by 20% fraction was 1850 U/ml. 

 

Key words: Amylase, Aspergillus carbonarius S-CSR-0002, raw starch, tapioca.