Evaluation of Activity of Polyphenoloxidase Enzyme and Intercalation of the Calcium Phosphate With Tetrabutylammonium Hydroxide

Abstract

Biosensors are digital devices composed of semiconductors connected to a biological component, usually an immobilized enzyme, which are used to measure the concentration of a specific substrate. This study aimed to obtain and purify the polyphenol oxidase enzyme (PPO) obtained from the crude extract of yam (Alocasia macrorhiza), and study the exfoliation reaction of calcium phosphate (CaP) with tetrabutylammonium hydroxide (TBA+OH-). The thermogravimetric study indicated the formation of the pyrophosphate phase above 400°C not only in CaP (white), but also in intercalated CaP with TBA+OH-. In addition, the intercalated CaP also presented mass losses between 350 and 400°C related to the elimination of the tetrabutylammonium. The value of enzymatic activity (860.00U / mL, buffer solution 0.10mol.dm-3, pH 7) suggests that the extracted enzyme from the yam has affinity towards the substrate (pyrogallol) used in this work. According to this result, it may be incorporated into the lamellae in the calcium phosphate.