Effect of various carbon and nitrogen sources on cellulose synthesis by Acetobacter lovaniensis HBB5
The effect of various carbon and nitrogen sources on cellulose production by Acetobacter lovaniensis HBB5 was examined. In this study, glucose, fructose, sucrose and ethanol as carbon source and yeast extract, casein hydrolysate and ammonium sulphate as nitrogen source were used. Among the carbon sources, glucose gave the highest yield, followed by fructose, sucrose and ethanol. Besides, among the nitrogen sources, yeast extract gave the highest yield, followed by casein hydrolysate and ammonium sulphate. In Hestrin-Schramm (HS) medium that contained 2% (w/v) glucose and 0.5% yeast extract, bacterial cellulose production was 0.040 g/l (dry weight) after 7 days. Morphological view of A. lovaniensis HBB5 strain and the bundle structure of cellulose which were produced at optimum conditions were monitored by scanning electron microscopy. From TLC analysis, glucose was found as the main content of the bacterial cellulose monosaccharide. Moreover, the chemical structure of the bacterial cellulose was examined by FT-IR and NMR spectrophotometers. FT-IR and NMR spectrophotometry revealed that, all the bacterial cellulose samples were highly crystalline and were of cellulose type I.
Key words: Acetobacter, cellulose, production, characterization.