Amylase from bacillus thuringiensis isolated from tapioca waste: isolation, partial purification and characterization

Abstract

Microorganism enzymes are the most widely used in industrial applications. Tapioca liquid waste could be a great source of amylase-producing bacteria. The aim of this research was to isolate the amylase-producing bacteria form the tapioca waste, to produce amylase and to purify the resulted amylase. The screening, identification, and the optimal production condition of the amylase‒producing bacteria were studied.  The optimization of bacteria production growth phase and the amylase production time were investigated. The crude amylase was purified using ammonium sulfate fractionation followed by SDS PAGE electrophoresis to identify the molecular weight and to purity of the amylase. The amylase activity assay used was based on the measuring of resulted reducing sugar by Somogyi-Nelson method. The result showed that the amylase producing bacteria was identified as Bacillus thuringiensis. The exponential phase of the bacteria growth for bacteria adaptation before production was 18 h and the optimal production time of amylase enzyme was 24 h. The highest specific activity of the purified amylase was fraction (FHD) 40% with specific activity of 37.56 ± 0.38U/mg. The SDS PAGE of FHD 40% profile showed two clear bands with molecular weight of 32 kDa and 35 kDa respectively