Fig. 4
Response surface plots and interaction plots for the influence of factors on the extraction efficiency of specialised metabolites of H. physodes using volatile natural deep eutectic solvents (VNADES). (a) The effect of liquid/solid ration (X2) and time (X4) on physodalic acid extraction yield. (b) The effect of liquid/solid ration (X2) and time (X4) on 3-hydroxyphysodic acid extraction yield; (c) the interaction effects of liquid/solid ration (X2) and temperature on 3-hydroxyphysodic acid extraction yield; (d) the effect of liquid/solid ration (X2) and time (X4) on physodic acid extraction yield; (e) the effect of liquid/solid ration (X2) and time (X4) on atranorin extraction yield; (f) the interaction effects of time (X4) and temperature (X3) on 3-hydroxyphysodic acid extraction yield; (g) the effect of liquid/solid ration (X2) and time (X4) on chloroatranorin extraction yield; (h) the effect of liquid/solid ration (X2) and time (X4) on cumulative lichen acids extraction yield; (i) the interaction effects of time (X4) and temperature (X3) on cumulative lichen acids extraction yield.
