Properties of an amylase from thermophilic Bacillus SP.

Abstract

α-Amylase production by thermophilic Bacillus sp strain SMIA-2 cultivated in liquid cultures containing soluble starch as a carbon source and supplemented with 0.05% whey protein and 0.2% peptone reached a maximum activity at 32 h, with levels of 37 U/mL. Studies on the amylase characterization revealed that the optimum temperature of this enzyme was 90ºC. The enzyme was stable for 1 h at temperatures ranging from 40-50ºC while at 90ºC, 66% of its maximum activity was lost. However, in the presence of 5 mM CaCl2, the enzyme was stable at 90ºC for 30 min and retained about 58% residual activity after 1 h. The optimum pH of the enzyme was found to be 8.5. After incubation of enzyme for 2 h at pH 9.5 and 11.0 was observed a decrease of about 6.3% and 16.5% of its original activity. At pH 6.0 the enzyme lost about 36% of its original activity. . In the presence of 2.0 M NaCl, 63% of amylase activity was retained after 2 h incubation at 45ºC. The amylase exhibited more than 70% activity when incubated for 1 h at 50ºC with sodium dodecyl sulphate. However, very little residual activity was obtained with sodium hypochlorite and with hydrogen peroxide the enzyme was completely inhibited. The compatibility of Bacillus sp SMIA-2 amylase with certain commercial detergents was shown to be good as the enzyme retained 86%, 85% and 75% of its activity after 20 min incubation at 50ºC in the presence of the detergent brands Omo ® , Campeiro ® and Tide ® , respectively.

Characteristics of a Novel Highly Thermostable and Extremely Thermophilic Alkalitolerant Amylase from Hyperthermophilic Bacillus Strain HUTBS71

“…The obtained data showed that the fractions from 60% ammonium sulfate saturation correlated with high proteolytic and specific activities compared with the crude amylase and other concentrations. Similar concentration of 60% saturation ammonium sulfate was used by Carvalho et al [15] to precipitate amylase from thermophilic Bacillus sp. strain SMIA2.…”

Isolation, Characterization and Optimization of Amylase Producing Micro-Organism from Gastrointestinal Tract of Catla Catla

“…Isolation and selection of suitable organisms is very essential for the production of extracellular α-amylase in abundance. Members of genus Bacillus were found to be better producer of amylase [23], [24], [25]. Some Bacillus produces the enzyme in the exponential phase, where as some others in the mid-stationary phase.…”

Isolation, characterization and identification of amylase producing halothermophilic isolates from Howz Soltan Lake, Iran

“…(Coronado et al, 2000;Amoozegar et al, 2003). Mostly, the scientists reported that amylase from halophilic Bacillus sp (Mathabatha, 2010) present an optimum production at 40 to 70°C (Carvalho et al, 2008). In addition Shafiei et al in 2010 showed that moderately halophilic bacterium Nesterenkonia sp.…”