• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.203-204
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• 2008

Bacterial Cellulose Actuator with biocompatible and biodegradable properties was newly developed as an electro-active biopolymer under water. The performance of the BC actuator was improved through Li treatment. The mechanical and chemical properties of BC membranes were measured such as the tensile test, proton conductivity. The surface morphology of the bacterial cellulose was observed by using SEM. The electromechanical bending responses under both direct current and alternating current excitations were investigated. In voltage-current test,the power consumption under dynamic excitation increases with increasing voltage. Present results show that the bacterial cellulose actuator can be a promising smart material and may possibly have diverse applications under water.

• KSBB Journal
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• v.18 no.2
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• pp.127-132
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• 2003

The effect of 4 kinds of alcohols was investigated on the production of bacterial cellulose (BC) by Gluconacetobacter hansenii PJK. The addition of alcohols and acetic acid to medium caused the pellets of bacterial cellulose to aggregate into a lump, which could be easily separated from the culture medium. The growth rate of cells and the production yield of BC increased in the medium containing ethanol. Other alcohols in the medium decreased cell growth and the cellulose production rate, because of their toxic effects. The addition of ethanol depressed the conversion of a $\textrm{Cel}^{+}$ cell to a $\textrm{Cel}^{-}$ mutant in shaking culture. Cells subcultured three in a medium containing ethanol produced BC without any loss of BC production yield.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.5
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• pp.289-294
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• 2002

Cellulose production by Acetobacter pasteurianus was investigated in static culture using four bioreactors with silicone rubber membrane submerged in the medium. The shape of the membrane was flat sheet, flat sack, tube and cylindrical balloon. Production rate of cellulose as well as its yield on consumed glucose by the bacteria grown on the flat type membranes was approximately ten-fold greater than those on the non-flat ones in spite of the same membrane thickness. The membrane reactor using flat sacks of silicone rubber membrane as support of bacterial pellicle can supply greater ratio of surface to volume than a conventional liquid surface culture and is promising for industrial production of bacterial cellulose in large scale.

• Food Industry And Nutrition
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• v.6 no.1
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• pp.10-14
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• 2001

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.6
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• pp.873-882
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• 2008

Eight ileally cannulated pigs (BW $35.9{\pm}0.9kg$) were randomly allotted according to a $4{\times}3$ Latin square design to determine the effects of cellulose, pectin and starch on standardized ileal digestibility (SID) and apparent total tract digestibility (ATTD) of crude protein (CP) and amino acids (AA) as well as on the bacterial AA contribution in feces. The pigs were fed the control diet (20.2% CP, % dry matter (DM)) or one of the three experimental diets in which 25% of the control diet was substituted by cellulose, starch or pectin. Due to this substitution, dietary CP levels were lower in the cellulose (15.5% CP, % DM), pectin (15.4% CP, % DM) and starch diet (15.2% CP, % DM). Following a 15-d adaptation period, feces were collected for 5 d and ileal digesta for a total of 24 h. Starch increased SID of CP, while cellulose and pectin had no significant effect on the digestibility of CP. Overall, starch supplementation resulted in higher (p<0.05) SID values of histidine, isoleucine, threonine, alanine, aspartic acid, cysteine, glycine and serine compared with cellulose, while pectin decreased (p<0.05) SID of valine and proline compared with the starch and control diet. Both cellulose and pectin reduced (p<0.05) the ATTD of CP and AA, while starch decreased (p<0.05) ATTD of phenylalanine, alanine, proline and serine compared with the control. With regard to bacterial AA composition of the fecal mixed bacterial mass (MBM), cellulose supplementation increased (p<0.05) its content of N and almost all AA, except for valine, while pectin caused higher contents of arginine, histidine and proline compared with the control (p<0.05). The bacterial contribution of arginine in feces was higher (p<0.05) in the cellulose treatment, while pectin reduced (p<0.05) the bacterial contribution of leucine, alanine, glutamic acid and proline in feces compared with the control. In conclusion, the effects of cellulose, starch and pectin on SID were rather small. Bacterial activity in the large intestine can only explain the reduced ATTD values for arginine in the cellulose treatment, but not for the other AA in the cellulose and pectin treatments, suggesting higher endogenous losses of these AA in the large intestine.

• Korean Journal of Microbiology
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• v.50 no.3
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• pp.227-232
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• 2014

In this study, Gluconacetobacter sp. gel_SEA623-2 isolated from citrus that produces bacterial cellulose was used to examine the effect of initial concentration of acetic acid and mixed culture inoculated with Lactobacillus plantarum KCCM 80077 on productivity of bacterial cellulose. In mixed culture added with 0.5% acetic acid, the viable cell count increased from $2.4{\times}10^6CFU/ml$ to $1.1{\times}10^7CFU/ml$ after 14 days of culture, and total acidity was about 0.3% higher than single culture added with 0.5% acetic acid, which implies that additional lactic acid was produced by L. plantarum KCCM 80077. In single culture, although bacterial cellulose productivity was higher when the initial concentrations of acetic acid were 0.0% and 0.5%, than when it was 1.0%, there was no significant difference. However, in mixed culture, adding 0.5% acetic acid resulted in dry weight of $37.83{\pm}6.81g/L$ and thickness of $10.33{\pm}0.58mm$, showing a significant difference from that of single culture added with 1% acetic acid, $28.40{\pm}1.23g/L$ and $7.50{\pm}0.50mm$ (P<0.05).

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.465-468
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• 2002

부패한 사과로부터 bacterial cellulose (BC)를 생산할 수 있는 균주를 분리한 후 배양조건에 따른 BC의 생산량을 조사한 결과 BC의 생산량은 진탕배양한 경우가 정치배양한 경우보다 약 1.5배 높았다. BC의 생산량을 높이고자 mutagen으로 UV와 cylcloheximide를 사용함으로써 BC 생산량을 약 3배 증가시킬 수 있었다.. 미생물에 의해 생성된 BC는 종이나 펄프와는 달리 pectin, 납, 유지, 단백질, 무기질 등의 불순물을 함유하지 않는 filter paper와 성질이 유사한 것으로 나타났다.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.376-376
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• 2016

Poly(ethylene oxide) (PEO)/functionalized bacterial cellulose nanowhiskers (f-BCNW) (0.1 wt%) composite nanofibers were fabricated by electrospinning process and the thermomechanical properties were significantly enhanced more than the PEO and PEO/bacterial cellulose nanowhiskers (BCNW) (0.1 wt%) composite nanofibers. The functionalization of BCNW (f-BCNW) was performed by microwave plasma treatment for effects of nitrogen functionalization of chemically-driven BCNW. The N-containing functional groups of f-BCNW enhanced chemical bonding between the hydroxyl groups of the polymer chains in the PEO matrix and diameter size of PEO/f-BCNW (0.1 wt%) composite nanofibers were decreased more than PEO and PEO/BCNW (0.1 wt%) composite nanofibers on the same concentration. The strong interfacial interactions between the f-BCNW nanofillers and polymer matrix were improved the thermomechanical properties such as crystallization temperature, weight loss and glass transition temperature (Tg) compared to PEO and PEO/BCNW composites nanofibers. The results demonstrated that N2 plasma treatment of BCNW is very useful in improving thermal stability for bio-applications.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.348-352
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• 2005

In this study, fermentation using a rotary biofilm contactor was conducted to improve bacterial cellulose production. We investigated the optimal fermentation conditions by using a newly isolated Gluconacetobacter sp. RKY5 in the rotary biofilm contactor. The optimal total area of discs was found to be 1,769 $cm^2$ at which bacterial cellulose and cell concentration was obtained to 5.52 g/L and 4.98 g/L, respectively. In case of aeration experiment, when the aeration rate was 1.25 vvm, the maximal bacterial cellulose (5.67 g/L) was obtained and cell concentration was 5.25 g/L.

• Journal of Life Science
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• v.12 no.5
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• pp.566-569
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• 2002

Acetobacter strains are bacteria that can synthesize cellulose when grown on an undefined medium containing glucose. Several culture conditions affecting cellulose production by Acetobacter sp. A9 were examined by cultivating cells under shaking cultures. The addition of buffering agents, such as 3-(N-morpholino) propanesulfonic acid (MOPS) and CaCO$_3$, increased cellulose production. It suggests that pH of culture medium is important to an economical mass cellulose production. Addition of bead (Ф10 w) to culture medium stimulated 'disintegrated bacterial cellulose' production.