Figure 1.
Sephadex LH-20 column chromatography for purification and fractionation of tannins from C. tagal leaves.
Subfraction 8 (F8) and Subfraction 9 (F9) were further fractionated into F8-1 to F8-4 and F9-1 to F9-3, respectively.
Figure 2.
Structural characterization of purified tannins (Fp) from C. tagal leaves.
Analyzed by (a) 13C-NMR, (b) reversed-phase HPLC-ESI-MS, (c) normal-phase HPLC-ESI-MS and (d) MALDI-TOF MS.
Figure 3.
Reflectron mode MALDI-TOF mass spectra for tannin subfraction F4 (a) to F9 (f).
Degree of polymerization (DP) of the predominant polymers and largest polymer in each mass spectrum of subfraction are labeled.
Figure 4.
Linear mode MALDI-TOF mass spectra for tannin subfraction F8 (a).
F8-1 (b) to F8-4 (e) were obtained by the further re-fractionation of F8. Degree of polymerization (DP) of the predominant polymers and largest polymer in each mass spectrum of subfraction are labeled.
Figure 5.
Linear mode MALDI-TOF mass spectra for tannin subfraction F9 (a).
F9-1 (b) to F9-3 (d) were obtained by the further re-fractionation of F9. Degree of polymerization (DP) of the predominant polymers and largest polymer in each mass spectrum of subfraction are labeled.
Table 1.
Mean degree of polymerization (mDP) and antioxidant activities of each subfraction obtained by fractionation of proanthocyanidins from C. tagal leaves.
Figure 6.
Regression analysis for mean degree of polymerization (mDP) and antioxidant activity.
(a) EC50/DPPH value and (b) FRAP value correlated with mDP for each proanthocyanidin subfraction from C. tagal leaves.