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Updated: Jun 19, 2026

Caffeine Extraction, Enzymatic Activity and Gene Expression of Caffeine Synthase from Plant Cell Suspensions
Published on: October 2, 2018
The interaction of lysozyme with caffeine, theophylline and theobromine in solution
Hong-Mei Zhang1, Bo-Ping Tang, Yan-Qing Wang
1Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection, Institute of Applied Chemistry and Environmental Engineering, Yancheng Normal College, 224002, Yancheng City, Jiangsu Province, People's Republic of China.
Abstract:
The interactions of lysozyme with caffeine (Caf), theophylline (Tph) and theobromine (Tbr) were investigated using UV-Vis absorption, fluorescence, synchronous fluorescence, and three-dimensional fluorescence spectra techniques. The results revealed that Caf (Tph or Tbr) caused the fluorescence quenching of lysozyme by the formation of Caf (Tph or Tbr)-lysozyme complex. The binding constants (K(A)) and thermodynamic parameters (ΔG°, ΔH°, ΔS°) at two different temperatures, the binding locality, and the binding power were obtained. The results showed that the process of binding Caf (Tph or Tbr) to lysozyme was a spontaneous molecular interaction procedure and the hydrophobic and electrostatic interactions play a major role in stabilizing the complex; The distance r between donor (lysozyme) and acceptor (Caf, Tph or Tbr) was obtained according to fluorescence resonance energy transfer. The effect of Caf (Tph or Tbr) on the conformation of lysozyme was analyzed using synchronous fluorescence and three-dimensional fluorescence spectra techniques. The results showed that the binding of Caf (Tph or Tbr) to lysozyme induced some micro-environmental and conformational changes in lysozyme and disturbed the environment of the polypeptide of lysozyme.
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