pH Dependence of Chitosan Enzymolysis
AbstractAs a means of making chitosan more useful in biotechnological applications, it was hydrolyzed using pepsin, chitosanase and α-amylase. The enzymolysis behavior of these enzymes was further systematically studied for its effectiveness in the production of low-molecular-weight chitosans (LMWCs) and other derivatives. The study showed that these enzymes depend on ion hydronium (H3O+), thus on pH with a pH dependence fitting R2 value of 0.99. In y = 1.484[H^+] + 0.114, the equation of pH dependence, when [H^+] increases by one, y (k_0/k_m) increases by 1.484. From the temperature dependence study, the activation energy (Ea) and pre-exponential factor (A) were almost identical for two of the enzymes, but a considerable difference was observed in comparison with the third enzyme. Chitosanase and pepsin had nearly identical Ea, but α-amylase was significantly lower. This serves as evidence that the hydrolysis reaction of α-amylase relies on low-barrier hydrogen bonds (LBHBs), which explains its low Ea in actual conditions. The confirmation of this phenomenon was further derived from a similarly considerable difference in the order magnitudes of A between α-amylase and the other two enzymes, which was more than five. Variation of the rate constants of the enzymatic hydrolysis of chitosan with temperature follows the Arrhenius equation. View Full-Text
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Gohi, B.F.C.A.; Zeng, H.-Y.; Pan, A.D.; Han, J.; Yuan, J. pH Dependence of Chitosan Enzymolysis. Polymers 2017, 9, 174.
Gohi BFCA, Zeng H-Y, Pan AD, Han J, Yuan J. pH Dependence of Chitosan Enzymolysis. Polymers. 2017; 9(5):174.Chicago/Turabian Style
Gohi, Bi Foua Claude Alain; Zeng, Hong-Yan; Pan, A Dan; Han, Jing; Yuan, Jian. 2017. "pH Dependence of Chitosan Enzymolysis." Polymers 9, no. 5: 174.
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