Abstract: 0.1% citric acid,malic acid,succinic acid,lactic acid,acetic acid,pyruvic acid was added to the defined medium to study their effects on cellulose production individually.The results showed that only lactic acid,acetic acid,pyruvic acid among the above organic acids could proliferate Acetobacter xylinum and enhance cellulose yield.When 0.4 % pyruvic acid added,yeild of cellulose was highest 2.02 g/L;When 0.3% lactic acid was added,yeild of cellulose was highest 2.16 g/L;When 0.4 % acetic was acid added,yeild of cellulose was highest 2.80 g/L;When 0.4% acetic acid,0.3%lactic acid and 0.4% pyruvic acid coexisted in the medium,the yeild was up to 4.45 g/L.

Key words: Acetobacter xylinum, organic acids, defined medium