Effects of Amino Acids in the Defined Medium on Cellulose Production by Acetobacter xylinum

17 amino acids were used to examine their effects on production of bacterial cellulose (BC) by Acetobacter xylinum. It found that these amino acids can be classified into three groups based on BC production: the efficient group (His/Glu/Asp/Thr/Leu/Ala/Cys), the less efficient one (Met/Ser/ Arg/PheNal/Pro/Try/Cystine/Tyr) and the non-efficient one (Lys). Among the efficient group, effects of amino acids on BC were insignificant except His through a L-8 (2(7)) factorial design, so it concluded that His was the best amino acid for BC produced by A. xylinum in defined medium. Even so, His was not the best nitrogen source, compared to ammonium sulphate. When His and ammonium sulphate co-existed in the medium, they were both comsumed by A. xylinum independently, but their synergic effect on BC production was not significant.