Table 6.
Optimum conditions, predicted and experimental values of responses

Response	Optimum ethanol extraction conditions			Maximum values
	Ethanol concentration (%)	Extraction temperature (°C)	Extraction time (min)	Predicted	Experimental
	Total phenolic content (mg GAE/g dry steam exploded oak wood	82.0	71.7	60.5	109.2	111.8 ± 1.3
DPPH radical scavenging activity (%)	78.3	70.3	57.6	62.3	65.7 ± 0.7
Antimicrobial activity (mm)	80.6	68.4	59.0	15.9	17.0 ± 0.8