Fig. 8

The mean comparison between the optimal points of different methods on total phenol content (according to the LSD test, the means with a common letter do not have a significant difference at the 1% probability level, (P < 0.01)).

The mean comparison between the optimal points of different methods on total phenol content (according to the LSD test, the means with a common letter do not have a significant difference at the 1% probability level, (P < 0.01)).