Figure 4. Response surface plot corresponding to (TT) of G. japonicum of (a) solvent type and extraction time; (b) solvent type and power; and (c) extraction time and power. The value of the missing independent variable in each plot was kept at the middle level

From

Response Surface Optimization for the Extraction of Antioxidant and Total Tannins from Geum Japonicum

Riyadh A.S. Thabit, Xiang-Rong Cheng, Nabil AL-hajj, Hua-Wei Shi, Xue Tang, Guo-Wei Le

Journal of Food and Nutrition Research. 2014, 2(6), 270-276 doi:10.12691/jfnr-2-6-1