Abstract: The objective of this study was to optimize ultrasonic-assisted extraction of phospholipid fatty acids (PLFAs) from forest soil using response surface methodology (RSM). Based on single factor experiments,extraction temperature,time and amount of extraction solvent were selected for Box-Behnken central composite designing. RSM was employed to study the effect of these factors on the yield of PLFAs.The results indicated that the optimal extraction conditions were 20 ℃ as extraction temperature,21 mL as amount of extraction solvent,with 30 min of extraction.Under these conditions,the maximal extraction yield reached 45.57 nmol/g (n=3).The response surface methodology used for the optimization of ultrasonic-assisted extraction conditions of PLFAs from forest soil was simple and reliable.

Key words: PLFAs, ultrasonic extraction, response surface methodology