Abstract:To screen the strains suitable for solid-state fermentation of Atrɑctylodes chinensis,the bacterial count and crude polysaccharide yield were used as screening indicators to obtain lactic acid bacteria for the fermentation of A. chinensis. On the basis of single factor experiments,response surface methodology was adopted to optimize the fermentation process with water content,inoculation amount,and fermentation time as factors.The results showed that three strains were screened and identified as Pediococcus ɑcidilɑctici and Pediococcus pentosɑceus by physiological and biochemical tests and 16S rDNA sequencing.The optimal fermentation conditions were water content 50%,inoculation amount 5.5% and 2 d fermentation. Under these conditions,the crude polysaccharide yield was 10.10%,an increase of 37.45% compared with the unfermented group.The antioxidant test revealed that fermentation significantly increased the scavenging ability of crude polysaccharides from A.chinensis against DPPH and hydroxyl radicals（P<0.05）.