Preparation of Spice Extracts: Evaluation of Their Phytochemical, Antioxidant, Antityrosinase, and Anti-α-Glucosidase Properties Exploring Their Mechanism of Enzyme Inhibition with Antibrowning and Antidiabetic Studies In Vivo

Figure 1

Mechanism of tyrosinase inhibition. (a) Lineweaver-Burk plot (LBP) for inhibition of tyrosinase enzyme in the presence of Star anise ETAC extract. The extract concentrations 0-13 μg/mL; however, L-DOPA concentrations ranging from 0.125 to 2 mM were used. (b) The insets represent the plot of the slope from LBP versus extract. (c) The secondary replot of the LBP, (-intercept) of versus various concentrations of extract. (d) The Dixon plot of the reciprocal of the initial velocities versus various concentrations of extract as inhibitor. (e) Relationship between the catalytic activity of L-DOPA and various concentrations of extract.

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