Certain strains of Acetobacter have been known to
produce cellulose in culture media. Acetobacter xylinum
is nature’s most prolific cellulose-producing bacterium
(1, 2).
The microbial cellulose is produced extracellularly in
the form of fibrils attached to the bacterial cell. Fibrils
from different cells are enmeshed to produce pellicles
which are mixtures of cellulose and cells. To date, the
processes for the production of microbial cellulose have
used static cultivation methods with the pellicles of
microbial cellulose being formed on the surface of the
static culture, which is usually contained in shallow
trays. The productivity using such methods is quite low
and this method is labor intensive. Therefore, for commercial
production, it is necessary to establish a mass
production system using the more productive agitated
culture technique.
Attempts to produce microbial cellulose in agitated
cultures have not been successful and microbial cellulose
have been produced with only low yields (3). The production
of cellulose from Acetobacter in agitated cultures is
beset by numerous problems, the greatest of which has
heretofore been culture instability. This instability is
demonstrated by loss of the ability to produce cellulose
and gradual replacement of cellulose-producing cells by
non-producing mutants (4).
Another problem associated with cellulose production
in agitated cultures of Acetobacter is the ability of
Acetobacter to convert glucose to gluconic acid and
ketogluconic acids (5). The production of gluconic and
ketogluconic acids remove glucose from the medium at
the expense of cellulose production.
Recently Toyosaki et al. (6) isolated a high celluloseproducing
strain, A. xylinum subsp. sucrofermentans
BPR2001, from agitated cultures. Following this, they
attempted to improve of this strain (7). Otherwise, there
have been few reports on microbial cellulose production
* Corresponding author.
with agitated culture systems (3, 8).
We have isolated a relatively stable cellulose-producing
strain from natural resources. This strain was identified
as A. xylinum BRCS. In this report, the effects of carbon
and nitrogen sources on the growth of, and cellulose
production by, strain BRCS in shaken and agitated cultures
have been studied. In addition, the characteristics
of carbon utilization of strain BRCS were analyzed.
Certain strains of Acetobacter have been known toproduce cellulose in culture media. Acetobacter xylinumis nature’s most prolific cellulose-producing bacterium(1, 2).The microbial cellulose is produced extracellularly inthe form of fibrils attached to the bacterial cell. Fibrilsfrom different cells are enmeshed to produce pellicleswhich are mixtures of cellulose and cells. To date, theprocesses for the production of microbial cellulose haveused static cultivation methods with the pellicles ofmicrobial cellulose being formed on the surface of thestatic culture, which is usually contained in shallowtrays. The productivity using such methods is quite lowand this method is labor intensive. Therefore, for commercialproduction, it is necessary to establish a massproduction system using the more productive agitatedculture technique.Attempts to produce microbial cellulose in agitatedcultures have not been successful and microbial cellulosehave been produced with only low yields (3). The productionof cellulose from Acetobacter in agitated cultures isbeset by numerous problems, the greatest of which hasheretofore been culture instability. This instability isdemonstrated by loss of the ability to produce celluloseand gradual replacement of cellulose-producing cells bynon-producing mutants (4).Another problem associated with cellulose productionin agitated cultures of Acetobacter is the ability ofAcetobacter to convert glucose to gluconic acid andketogluconic acids (5). The production of gluconic andketogluconic acids remove glucose from the medium atthe expense of cellulose production.Recently Toyosaki et al. (6) isolated a high celluloseproducingstrain, A. xylinum subsp. sucrofermentansBPR2001, from agitated cultures. Following this, theyattempted to improve of this strain (7). Otherwise, therehave been few reports on microbial cellulose production* Corresponding author.with agitated culture systems (3, 8).We have isolated a relatively stable cellulose-producingstrain from natural resources. This strain was identifiedas A. xylinum BRCS. In this report, the effects of carbonand nitrogen sources on the growth of, and celluloseproduction by, strain BRCS in shaken and agitated cultureshave been studied. In addition, the characteristicsof carbon utilization of strain BRCS were analyzed.
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