The starch hydrolysis by α-amylase Bacillus spp.: an estimation of the optimum temperatures, the activation and deactivation energies
Justyna Miłek, Jan Lamkiewicz
Abstract
Abstract Amylases have potential application, inter alia, in processes with starch hydrolysis. The present paper reports the estimation of the optimum temperatures, the activation and deactivation energies of starch hydrolysis by $${\alpha }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>α</mml:mi> </mml:math> -amylase Bacillus spp. The literature activity of $${\alpha }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>α</mml:mi> </mml:math> -amylase Bacillus spp. versus temperature curves was analyzed. The mathematical model presented the activity of $${\alpha }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>α</mml:mi> </mml:math> -amylase Bacillus spp. and the starch hydrolysis. Both the starch hydrolysis and the deactivation process of $${\alpha }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>α</mml:mi> </mml:math> -amylase were analyzed by the first-order equations according to the enzyme concentration. Determined optimum temperatures $${T}_\textrm{opt}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>T</mml:mi> <mml:mtext>opt</mml:mtext> </mml:msub> </mml:math> were in the range from $$323.67 \pm 1.48$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>323.67</mml:mn> <mml:mo>±</mml:mo> <mml:mn>1.48</mml:mn> </mml:mrow> </mml:math> K to $$354.00 \pm 2.27$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>354.00</mml:mn> <mml:mo>±</mml:mo> <mml:mn>2.27</mml:mn> </mml:mrow> </mml:math> K, activation energies $$E_\textrm{r}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>E</mml:mi> <mml:mtext>r</mml:mtext> </mml:msub> </mml:math> were in the range from $$18.01 \pm 7.22$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>18.01</mml:mn> <mml:mo>±</mml:mo> <mml:mn>7.22</mml:mn> </mml:mrow> </mml:math> kJ mol -1 to $$102.85 \pm 20.53$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>102.85</mml:mn> <mml:mo>±</mml:mo> <mml:mn>20.53</mml:mn> </mml:mrow> </mml:math> kJ mol -1 , and the values of deactivation energies $$E_\textrm{d}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>E</mml:mi> <mml:mtext>d</mml:mtext> </mml:msub> </mml:math> were in the range from $$79.76 \pm 8.77$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>79.76</mml:mn> <mml:mo>±</mml:mo> <mml:mn>8.77</mml:mn> </mml:mrow> </mml:math> kJ mol -1 to $$162.85 \pm 32.23$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>162.85</mml:mn> <mml:mo>±</mml:mo> <mml:mn>32.23</mml:mn> </mml:mrow> </mml:math> kJ mol -1 . The present study is related to the starch hydrolysis by $${\alpha }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>α</mml:mi> </mml:math> -amylase Bacillus spp. The obtained results might find application in the industry hydrolysis of starch.