Abstract

The effect of solvent concentration and time on the extraction efficiency of tannins from root, stem, leaves, and seeds of Cichorium intybus L. was studied. A 2²-factorial central composite design was employed by using response surface methodology to optimize the extraction conditions. The analysis of variance showed the significant effect of both variables on the extraction yield of tannins. The lower P-values (P < 0.05) indicated the positive significant effect of both variables on the extraction of tannins from different parts ofC. intybus. The values of correlation coefficient (R²) indicated that more than 96% of the variability in tannins content of C. intybus could be explained by response surface model. The 3D surface plots showed a quadratic effect of methanol concentration and linear effect of time on the extraction efficiency of tannins from C. intybus. The optimum tannins yield of 0.607, 0.529, 0.26, and 0.431 g/100 g dry weight from root, stem, leaves, and seeds of C. intybus, respectively was observed at 60% methanol concentration and extraction time of 80 min. Moreover, the data suggests that C. intybus is a rich source of tannins and can be preferably used to fulfil the requirements of tannins in medicinal field.

Key words: Cichorium intybus L., chicory, medicinal plants, tannins extraction, central composite design (CCD), response surface methodology (RSM).