A bacterial strain with morphological and biochemical properties close to Acetobacter xylinum has been cultured in nonagitated, inverted sucrose- and yeast water-based medium for the production of thick, smooth, and floating cellulosic pellicles. The cellulose content (greater than 90%, dry weight, depending on the efficiency of water washing) and the beta-D-homopolyglucan nature of these pellicles were assessed by physical, chemical, and enzymatic methods. The apyrogenic bacterial biomass, a minor component of the dried biofilm (BioFill), is inactivated by ethylene dioxide. Once applied on exudating or bloody tissues, this biofilm displays several advantages as a biological dressing, and hence, it is valuable as a temporary skin substitute in the treatment of skin wounds, such as burns, ulcers, grafts, and as an adjuvant in dermal abrasions.

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Caffeine and related xanthines were identified as potent stimulators for the bacterial cellulose production in A. xylinum. These compounds are present in several plants whose infusions are useful as culture-medium supplements for this acetobacterium. The proposed target for these native purine-like inhibitory substances is the novel diguanyl nucleotide phosphodiesterase(s) that participate(s) in the bacterial cellulogenic complex. A better understanding of this feature of A. xylinum physiology may facilitate the preparation of bacterial cellulose pellicles, which are applied as a biotechnological tool in the treatment of skin burns and other dermal injuries.

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