• 펄프종이기술
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• 제29권4호
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• pp.53-63
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• 1997

Most cellulose resources come from the higher plants, but bacteria also synthesize same cellulose as in plants. Many scientists have been widely studied on the bacterial cellulose, the process development, manufacturing, even marketing of cellulose fibers. The bacterial celluloses are very different in its physical and morphological structures. These fibers have many unique properties that are potentially and commercially beneficial. The fine fibers can produce a smooth paper with enchanced its strength property. But there gave been few reports on the mechanical properties of the processing of bacterial cellulose into structural materials. This study were performed to elucidate the mechanical properties of sheets prepared from bacterial cellulose. Also reinforcing effect of bacterial cellulose on the conventional pulp paper as well as surface structures by scanning electron microscopy were discussed. Paper made from bacterial cellulose is 10 times much stronger than ordinary chemical pulp sheet, and the mixing of bacterial cellulose has a remarkable reinforcing effect on the papers. Mechanical strengthes were increased with the increase of bacterial cellulose content in the sheet. This strength increase corresponds to the increasing water retention value and sheet density with the increase of bacterial cellulose content. Scanning electron micrographs were shown that fine microfibrills of bacterial celluloses covered on the surfaces of hardwood pulp fibers, and enhanced sheet strength by its intimate fiber bonding.

• 한국식품영양과학회지
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• 제31권4호
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• pp.572-577
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• 2002

Gluconacetobacter persimmonus KJ145를 사용하여 bacterial cellulose 생산에 최적 배지와 배양조건을 설정하였다. Bacterial cellulose를 생성하기 위한 최적배지로는 HS배지보다는 천연사과과즙이 더 우수한 경향을 나타내었으며, 사과과즙에 각종 탄소원을 보강한 결과 탄소원으로 pyruvate가 적합하였다. 탄소원의 농도를 조사한 결과, 1%가 적합하였으며, 각종 질소원의 영향을 조사한 결과 CSL이 가장 우수한 결과를 나타내었다. CSL의 농도에 따른 bacterial cellulose의 생산성을 조사한 결과, 10% 농도에서 가장 좋았다. Bacterial cellulose의 생성에 미치는 배지의 초기 pH의 영향을 조사한 결과 pH 6.0에서 최적이었으며,배양온도별 영향을 조사한 결과 35$^{\circ}C$에서 하는 것이 최적이었다. 최적 배양조건에서 배양시간별로 생성되는bacterial cellulose의 양을 조사한 결과 16일간 배양하는 것이 가장 좋았으며, 이 때 생성되는 bacterial cellulose의 생산량은 8.96 g/L으로 비교적 높았다.

• 펄프종이기술
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• 제30권4호
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• pp.35-41
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• 1998

The bacterial cellulose has many unique properties that are potentially and commercially beneficial. In order to make opaque product from this cellulose, filling properties by fillers should be known. This study was performed to investigate the effect of filler addition on physical properties of sheets from bacterial cellulose. The effect of filling on its optical properties was also discussed. The apparent density and internal bonding strength of bacterial cellulose sheet are decreasing with the increase of filler contents. Those adversely affect Young's modulus and physical property of the sheet, but these negative phenomena of the bacterial cellulose sheet by filler addition are not so sensitive compared to substantial decreasing of physical properties of ordinary hardwood KP. This strength decrease would be attributed to the decrease of relative bonding sites among pulp fibers. Concerned to optical properties, the bacterial cellulose sheet shows high increase of brightness and opacity according to filler loading, but no significant changes in porosity up to 17.3% loading because of fine and filamentous structure of bacterial cellulose fibers.

• 한국식품저장유통학회지
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• 제12권5호
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• pp.455-459
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• 2005

본 연구에서는 BC를 백설기에 첨가하여 저장 중 품질특성을 조사하였다. 그 결과, bacterial cellulose 0.09%이상 첨가한 백설기가 무첨가구에 비해 저장동안 노화도가 낮게 나타났다. 또한 hardness를 측정한 결과 BC첨가를 첨가한 구간들에서 hardness가 낮게 나타나 노화억제효과가 있었다. 관능검사 결과 거의 모든 평가항목에서 시료들 간의 유의적인 차이가 없었으나, 전반적인 기호도에서 BC를 첨가한 백설기가 더 좋은 것으로 나타났다.

• 한국정밀공학회지
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• 제29권3호
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• pp.302-306
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• 2012

Bacterial cellulose based actuator with large displacement was developed for biomimetic robots. Bacterial cellulose has 3D nanostructure with high porosity which was composed of the nanofibers. Freeze dried bacterial cellulose was dipped into ionic liquid solution such as 1-butyl-3-methylimidazolium(BMIMCl) to enhance the actuation performance due to increase the ionexchange capacity and ionic conductivity. And Poly(3,4-ethylenedioxythiophene)-poly (styrnenesulfonate)(PEDOT:PSS) was used for the electrodes of both side of bacterial cellulose actuator by dipping and drying method. The FT-IR and XRD were conducted to examine the electrochemical changes of developed bacterial cellulose actuator. The biomimetic caudal fin was designed using bacterial cellulose actuator and PDMS to verify the possibility for biomimetic robot. The step and harmonic response were conducted to evaluate the performance of developed biomimetic actuator.

• 한국식품영양과학회지
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• 제32권2호
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• pp.181-184
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• 2003

G. persimonensis-KJ145를 차용하여 BC 생산과 식초생산에 미치는 에탄올의 영향을 조사하였다. 그 결과 사과쥬스배지에 에탄올을 2%(v/v) 첨가하였을 때 BC의 생산성이 가장 좋았으며, 7%(v/v)를 첨가하였을 때 총산의 함량이 가장 높았다. BC와 식초를 동시 생산하기 위해서는 에탄올을 5%(v/v) 첨가하는 것이 가장 좋을 것으로 생각되며 발효과정 중의 식초 품질 변화에 대한 보다 자세한 연구가 요구되었다. BC와 식초 생산에 가장 효과적인 질소원은 CSL인 것으로 조사되었고 최적 농도는 15%(w/v)이었다. 배양시간의 영향을 조사한 결과 14일간 배양하는 것이 가장 많은 양의 BC를 생산하였으며, 최적조건에서 생산되는 BC 생산량은 7.55 g/L이었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권2호
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• pp.83-88
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• 2003

A cellulose-producing strain isolated from rotten apples was identified as Gluconacetobacter hansenii based on its physiological properties and the 16S rDNA complete sequencing method, and specifically named Gluconacetobacter hansenii PJK. The amount of bacterial cellulose (BC) produced by G. hansenii PJK in a shaking incubator was 1.5 times higher than that produced in a static culture. The addition of ethanol to the medium during cultivation enhanced the productivity of bacterial cellulose, plus the supplementation of 1% ethanol into the culture medium made the produced BC aggregate into a big lump and thus protected the bacterial-cellulose-producing G. hansenii PJK cells in the shear stress field from being converted into non-cellulose-producing (Cel) mutants. Cells subcultured three times in a medium containing ethanol retained their ability to produce BC without any loss in the production yield.

• 펄프종이기술
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• 제29권3호
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• pp.26-33
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• 1997

The bacterial celluloses are very different in its physical, chemical and morphological structures compared to wood cellulose. These fibers have many unique properties that are potentially and commercially beneficial. This study was aimed to elucidate the production of bacterial celluloses and to improve their physical properties by chemical pretreatment. Bacterial celluloses produced by static culture had gel-like pellicle structure. The pellicle thickness was increased with the increasing time, and its layer was about 1.8cm after one-month incubation. The pellicles extruded from the cells of Acetobacter had a non-crystalline structure during initial growing stages, gradually getting crystaliyzed with the incubation time elapse, and eventually fumed to the cellulose I crystals. Young＇s modulus of bacterial cellulose sheet was increased with increasing NaOH concentration, and resulted in the highest at 5% NaOH concentration. Similar results with NaClO3 pretreatment can be observed. Too concentrated alkali solutions induced the destruction of cellulose fibrils and changed the mechanical properties of the sheets. These alkaline pretreatment have removed non-cellulosic components(NCC) from the bacterial cellulose, and enhanced inter-abrillar bonding by direct close contact among cellulosic fibrils.

• 폴리머
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• 제34권6호
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• pp.522-526
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• 2010

Bacterial cellulose는 초산균인 Gluconacetobacter xylinus에 의해 생산되며, 배양 배지의 표면에 나노섬유상의 막을 형성한다. 본 연구에서는 배지의 조성에서 탄소원을 달리하여 생산한 bacterial cellulose의 결정화도, 점도, 모폴로지와 역학적 물성을 살펴보았다. Gluconacetobacter sp. V6 균은 세 종류의 배양 배지에서 정치 상태로 배양되었다. 배양 배지로는 표준 Hestrin-Schramm 배지와 탄소원으로 glycerol 또는 molasses를 첨가한 개질 배지가 각각 사용되었다. 세포 성장과 셀룰로오스 수율은 molasses 배지와 glycerol 배지에서 증가하였다. Glycerol 배지를 사용한 배양은 결정화도와 고유점도, 파단응력과 같은 셀룰로오스의 물성을 향상시켰으나, molasses 배지를 사용한 배양은 셀룰로오스의 결정화도, 미결정의 크기, 고유점도를 감소시켰다. 요약하면, molasses 배지에서 셀룰로오스의 수율은 현저히 향상되었으나, 낮은 구조적 물성을 가졌다.

• 한국식품영양과학회지
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• 제32권7호
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• pp.981-985
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• 2003

G. persimmonis KJ145$^{T}$ 를 사용하여 bacterial cellulose와 식초 동시 생산에 따른 성분변화를 조사하였다. 그 결과 pH는 배양 8일째에 3.22로 감소하는 경향이었으며, 총산은 8일째에 가장 높은 4.66으로 나타났다. Brix는 배양기간 동안 거의 변화가 없었으며, 유리당은 fructose, glucose 및 sucrose로 구성되어 있고 fructose는 배양 종료 후, 10일째에도 거의 감소하지 않고 높게 나타났다. G. Persimmonis KJ145$^{T}$ 균체는 배양 2일부터 급격히 증가하여 4일에 가장 높게 나타났으며, bacterial cellulose는 배양기간이 길수록 증가하는 경향을 나타내었다. 발효액의 유기산은 malic acid, succinic acid, oxalic acid 등이 검출되었으며, acetic acid는 발효 2일째부터 급격히 증가하여 8일째에 가장 높게 생성되었다. 따라서 bacterial cellulose와 초산을 동시에 생산하기 위한 최적배양기간은 8일 정도로 나타났다.