Evaluation of Free Radical-Scavenging Activity of Sea Urchin Pigments Using HPTLC with Post-Chromatographic Derivatization
Chromatographic separation, analysis of in situ radical-scavenging activity, and quantitative analysis of green sea urchin shell pigments were carried out by online HPTLC-DAD and HPTLC-DPPH methods. Methanol:chloroform:acetic acid:water (11:50:5:2, v/v) was selected as the best mobile phase on silica gel plates for the separation of the pigments. Two pigment spots, S1 and S2, were observed on the TLC plates, while echinochrome A was not detected in the pigment extract of green sea urchin shells. Based on the estimated ID50 values, the antiradical activity was S2 (0.043 μg) > S1 (0.058 μg) > echinochrome A (0.134 μg).