Formation of antioxidants from (-)-epigallocatechin gallate in mild alkaline fluids, such as authentic intestinal juice and mouse plasma.

@article{Yoshino1999FormationOA,
  title={Formation of antioxidants from (-)-epigallocatechin gallate in mild alkaline fluids, such as authentic intestinal juice and mouse plasma.},
  author={K. Yoshino and M. Suzuki and K. Sasaki and T. Miyase and M. Sano},
  journal={The Journal of nutritional biochemistry},
  year={1999},
  volume={10 4},
  pages={
          223-9
        }
}
The oxidative dimerization of (-)-epigallocatechin gallate (EGCG), the major catechin of tea leaves (Camellia sinensis L.), in authentic intestinal juice (pH 8.5) and mouse plasma (pH 7.8) was investigated. EGCG was unstable in the alkaline solutions over pH 7.4. The content of EGCG was decreased to 19.4% and 60.7% at 5 minutes in the intestinal juice and plasma, respectively. Three products-P-1 (theasinensin A), P-2 (a new dimerized product reported in a previous paper), and P-3 (theasinensin… Expand
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