Study on purification of catechins by C18 column chromatography

To obtain high-purity catechin monomers, the separation effect of AB-8 macroporous absorption resin, polyamide resin, silica gel, C18 by preparative medium pressure liquid chromatography ( MPLC) was investigated.C18 was chosen as the best filling materials to separate catechins components in condition of the different injection volume of tea polyphenols and different flow rates.The optimum technological conditions was as followed: C18 as packing material, methanol /water as eluting solvent, injection volume 350 mg, flow rate 20 mL /min. EGCG, GCG, ECG, CG were achieved with their yield of 36.19% ± 0.11%, 7.42% ± 0.14%, 12.93% ± 0.18%, 2.40% ± 0.22% and purities were 88.85% ± 0.17%, 83.74% ± 0.09%, 96.01% ± 0.13%, 70.67% ± 0.11%, respectively.The total recovery of all catechins was 68.44%. With easy operation and high yield, this process could be helpful to the efficient preparation of catechin monomers from tea polyphenols and met industrialized production.