• Journal of Microbiology and Biotechnology
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• 제29권9호
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• pp.1412-1423
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• 2019

The filamentous fungus Aspergillus tubingensis that belongs to the black Aspergillus section has the capacity to produce high-value metabolites, for instance, naphtho-gamma-pyrones (NGPs). For these fungal secondary metabolites, numerous biological properties of industrial interest have been demonstrated, such as antimicrobial, antioxidant and anti-cancer capacities. It has been observed that production of these secondary metabolites is linked with fungal sporulation. The aim of this research was to apply osmotic and oxidative environmental stresses to trigger the production of NGPs in liquid cultures with CYB (Czapek Dox Broth). In addition, numerous parameters were tested during the experiments, such as pH value, incubation time, container geometry, and static and agitation conditions. Results demonstrate that the produced amount of NGPs can be enhanced by decreasing the water activity ($a_w$) or by adding an oxidative stress factor. In conclusion, this study can contribute to our knowledge regarding A. tubingensis to present an effective method to increase NGP production, which may support the development of current industrial processes.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권5호
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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.

• 한국버섯학회지
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• 제17권4호
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• pp.185-190
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• 2019

리그닌 분해 담자균류로 알려져 있는 느타리버섯균 No.42는 망간퍼옥시데이즈(MnP) 및 락게이즈(Lac)를 생산하였으나 글루코오스-펩톤-이스트-밀기울(GPYW)배지를 이용한 정치배양조건하에서 리그닌퍼옥시데이즈(LiP)활성은 검출되지 않았다. 한편, 동일배지에서 망간퍼옥시데이즈 활성은 11일째 80(3.6) U/flask(ml)의 최대 생산되었다. 망간퍼옥시데이즈 분리정제는 Sepha-ros CL-6B 및 Mono-Q 컬럼순으로 수행하였으며 주요 망간퍼옥시데이즈 isozyme은 단일밴드로 분자량은 36.4KDa이였다. N-말단으로부터 19개의 아미노산 배열은 단백질 자동 분석 장치로 분석한 결과 ATCADGRTTANAACCVLFP를 나타내었다. 느타리버섯균 No.42의 정치배양조건 하에서 세포외로 생산되는 중요한 망간퍼옥시데이즈 isozyme의 N-말단 아미노산 배열은 이전에 보고된 MnP3의 아미노산 배열과 동일하였다.

• Journal of Microbiology and Biotechnology
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• 제20권2호
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• pp.254-264
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• 2010

To obtain an efficient natural lignocellulolytic complex enzyme, we screened an efficient lignocellulose-degrading composite microbial system (XDC-2) from composted agricultural and animal wastes amended soil following a long-term directed acclimation. Not only could the XDC-2 degrade natural lignocelluloses, but it could also secrete extracellular xylanase efficiently in liquid culture under static conditions at room temperature. The XDC-2 degraded rice straw by 60.3% after fermentation for 15 days. Hemicelluloses were decomposed effectively, whereas the extracellular xylanase activity was dominant with an activity of 8.357 U/ml on day 6 of the fermentation period. The extracellular crude enzyme noticeably hydrolyzed natural lignocelluloses. The optimum temperature and pH for the xylanase activity were $40^{\circ}C$ and 6.0. However, the xylanase was activated in a wide pH range of 3.0-10.0, and retained more than 80% of its activity at $25-35^{\circ}C$ and pH 5.0-8.0 after three days of incubation in liquid culture under static conditions. PCR-DGGE analysis of successive subcultures indicated that the XDC-2 was structurally stable over long-term restricted and directed cultivation. Analysis of the 168 rRNA gene clone library showed that the XDC-2 was mainly composed of mesophilic bacteria related to the genera Clostridium, Bacteroides, Alcaligenes, Pseudomonas, etc. Our results offer a new approach to exploring efficient lignocellulolytic enzymes by constructing a high-performance composite microbial system with synergistic complex enzymes.

• 생약학회지
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• 제26권4호
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• pp.419-425
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• 1995

Corydalis remota Fish. ex Max. (Papaveraceae) is a well known medicinal plant being used as analgesics or anticonvulsive in oriental medicine. As the alkaloid content is known to vary depending on the environmental factors, the technology of plant tissue culture can be adopted as source of Corydalis-alkaloids. The present study describes an establishment of tissue cultures of Corydalis which produce alkaloids consistently. Callus were induced from immature seeds of Corydalis remota by placing the seeds on MS static media containing NAA(0.25, 1.0 and 4.0 mg/l, respectively). The combined treatment of NAA(1.0 mg/l) with cytokinin(BAP 0.5 mg/l) improved the induction of callus. TLC scanning data followed by sequential extraction and purification revealed that the induced callus contains a significant amount of alkaloids. Cell suspension cultures were established by transferring the induced callus into the liquid media with the same condition of plant growth regulators as the callus culture.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권1호
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• pp.26-31
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• 2006

The saccharogenic liquid (SFW) obtained by the enzymatic saccharification of food wastes was used as a medium for production of bacterial cellulose (BC). The enzymatic saccharification of food wastes was carried out by the cultivation supernatant of Trichoderma harziaum FJ1 culture. Acetobacter xylinum KJ1 was employed for the BC production culture. The physical properties, such as polymerization, crystallinity, Young's modulus, and tensile strength, of BCs produced by three culture methods: the static cultures using HS (Hestrin-Schramm) as a reference medium (A) or the SFW medium (B), the shaking culture (C) or the air circulation culture (D) using the SFW medium, were investigated. The degrees of polymerization of BCs produced under the different culture conditions (A-D) showed 11000, 9500, 8500, and 9200, respectively. Young's modulus was 4.15, 5.0, 4.0, and 4.6 GPa, respectively. Tensile strength was 124, 200, 80, and 184 MPa, respectively. All of the BC had a form of cellulose I representing pure cellulose. In the case of the shaking culture, the degree of crystallinity was 51.2%, the lowest degree. Under the other culturing conditions, the trend should remain in the range of 89.7-84%. Overall, the physical properties of BC produced from SFW were similar to those of BC from HS medium, a commercial complex medium, and BC production by the air circulation culture mode brought more favorable results in terms of the physical properties and its ease of scale-up. Therefore, it is expected that a new BC production method, like air circulation culture using SFW, would contribute greatly to BC-related manufacturing.

• Journal of Microbiology and Biotechnology
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• 제30권1호
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• pp.93-100
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• 2020

A bacterial strain inhibiting the growth of Vibrio anguillarum, the causative agent of vibriosis, was isolated from fish intestines. The isolated strain HS36 was identified as Aerococcus urinaeequi based on the characteristics of the genus according to Bergey's Manual of Systematic Bacteriology and by 16S rRNA sequencing. The growth rate and antibacterial activity of strain HS36 in shaking culture were higher than those in static culture, while the optimal pH and temperature for antibacterial activity were 7.0 and 30℃, respectively. The active antibacterial substance was purified from a culture broth of A. urinaeequi HS36 by Sephadex G-75 gel chromatography, Sephadex G-25 gel chromatography, and reverse-phase high-performance liquid chromatography. Its molecular weight, as estimated by Tricine SDS-polyacrylamide gel electrophoresis, was approximately 1,000 Da. The antibacterial substance produced by strain HS36 was stable after incubation for 1 h at 100℃. Although its antibacterial activity was optimal at pH 6-8, activity was retained at a pH range from 2 to 11. The purified antibacterial substance was inactivated by proteinase K, papain, and β-amylase treatment. The newly purified antibacterial substance, classified as a class II bacteriocin, inhibited the growth of Klebsiella pneumoniae, Salmonella enterica, and Vibrio alginolyticus.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.469-472
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• 2002

균체 생산성 실험과 chitinase 생산성 실험을 비교해 볼 때, chitinase만을 생산하는 조건 에서는 배지성분에 chitin을 첨가해 주는 것이 좋으나, 해충 방제용으로 살균력을 증진시키기 위하여 균체량과 chitinase의 생성량 및 산업적, 경제적 사용이 용이한 배지를 고려할 때에는 쌀겨와 밀기울이 첨가된 배지가 좋은 배지임을 알 수 있었다. 또한 이 배지를 이용하였을 경우 균체는 1X$10^8$ cfu/g, chitinase는 370mU/g로 생산되었으며 생물검정결과 53-64%의 탁월한 살충효과를 확인 할 수 있었다.

• KSBB Journal
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• 제22권2호
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• pp.91-96
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• 2007

본 연구에서는 음식폐기물 효소당화액을 BC생산 배지원으로 이용하여, flask정치배양과 50 L로 규모확대한 공기순환배양기에서 BC생산성을 검토하고, 생산된 BC의 제반물성을 조사하였다. 전단력을 낮추기 위해 당화액배지에 agar를 첨가하여 10 L, 50 L 공기순환배양기에서 배양한 결과, 50 L 규모로 scale-up한 반응기에서 5.64 g/L로 10 L 공기순환배양기 (5.84 g/L)에서와 동등한 BC 농도가 얻어져 BC 대량생산에 효과적인 배양방법임이 입증되었다. 50 L 규모로 확대된 공기순환배양기를 이용하는 본 배양 방법은 BC의 저비용 대량생산을 위한 효율적인 생산 방법 중 하나가 되리라 사료된다. 또한, 당화액을 배지로 하여 공기순환 방법으로 제조한 BC의 물성을 정치배양 방법으로 제조한 BC의 물성과 비교 검토한 결과, 공기순환법으로 제조하였을 때 중합도 및 역학적 성질이 약간 저하하였으나 결정성은 비슷하였으며, 배양기 용량의 대소에 따른 물성의 변화는 거의 없었다.

• 한국균학회지
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• 제15권3호
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• pp.158-168
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• 1987

1. Cassava 전분(澱粉)을 이용(利用)하여 곰팡이를 $28^{\circ}C$에서 96시간(時間) 액체정치(液體定置) 배양(培養)한 바 배지중(培地中)의 Cassava 전분함량(澱粉含量)이 6%, 72시간(時間)일 때에 균체량(菌體量)이 가장 많았다. 2. Cassava 전분(澱粉)이 6% 함유(含有)된 배지(培地)에서 곰팡이를 배양(培養)하여 얻은 균체단백질량(菌體蛋白質量)은 Rhizopus는 48시간(時間) 배양(培養)하였을때 가장 많았고, Aspergillus niger 및 Aspergillus fumigatus에서는 72시간(時間) 배양(培養)했을 때 균체단백질량(菌體蛋白質量)이 많았다. 3. Cassava 전분량(澱粉量)을 4%, 6% 및 8%되게 변화(變化)시킨 배지(培地)에서 분리균(分離菌)을 접종(接種)하여 96시간(時間) 배양(培養)하면서 24시간(時間)마다 배양여액(培養濾液) 중(中)의 m-amylase의 활성(活性)을 측정(測定)한 바 8% 농도(濃度)에서 Aspergillus niger 및 Aspergillus fumigatus는 72시간(時間)일 때 높은 D.P 값을 얻었고. Rhizopus 는 144시간(時間)일 때 D.P 값이 높았다.