• 한국균학회지
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• 제27권4호통권91호
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• pp.299-303
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• 1999

Aspergillus ficuum이 발효조의 배양액에서 phytase를 가장 많이 분비 생산하는 시간은 5일째였다. 이 phytase를 ultrafiltration, cation exchange column, 그리고 anion exchange column으로 최종 정제하여 SDS-PAGE로 분석하여 본 결과 단일 band로 약90,000의 분자량을 가진 것으로 나타났다. 정제된 phytase를 사용하여 phytase에 대한 항체를 생산하였고 titer는 1/25,000로 결정하였다.

• 한국미생물·생명공학회지
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• 제19권3호
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• pp.253-258
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• 1991

Aspergillus ficuum이 생산하는 exoniulinase가 CM-Sephadex, DEAE-Sepharose 6B, 및 HPLC gel filtration을 통해 단백질 mg당 약 2,800U의 specific activity로 정제되었다. 이 효소는 native 상태에서 약 83,000+1,000의 분자량을 나타냈으며 당을 함유하고 있었다. 이 효소는 최적 pH가 4.4-4.7이었고, 55'C에서 8시간 노출 후에도 그 활성을 95 유지하였다. 이 효소의 I/S ratio는 약 0.35이고 전형적인 non-speific Beta-fructofuranosidase의 특성을 나타내었으며 raffinose와 stachyose를 분해할 수 있었다.

• Mycobiology
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• 제28권3호
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• pp.119-122
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• 2000

Phytases (myo-inositol hexakisphosphate phosphohydrolase; EC 3.1.3.8) are enzymes which catalyze the hydrolisys of phytate into myo-inositol and inorganic phosphates. Phytases are found in plants and a variety of microorganisms. Aspergillus species were treated with 254 nm of UV irradiation for the screening of phytase overproducing mutant strains. At 15 minute irradiation, the survivals of population were less than 5%, and UV irradiation time was decided at 20 minute for the isolation of mutant strains. Four UV mutant strains in A. oryzae (YUV-47, -169, -341, -511) and six in A. ficuum (FUV-17, -36, -69, -193, -317, -419) were isolated on PSM media containing ammonium phosphate. The specific enzyme activities of A. ficuum mutants are 110 to 140% higher than that of wild type.

• 한국미생물·생명공학회지
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• 제19권2호
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• pp.158-162
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• 1991

Endoinulinase was purified from a commercial inulin preparation produced by Aspergillus ficuum using ion exchange chromatography on CM-Sephadex C-50 and DEAE-Sepharose 6B, HPLC gel filtration on a Protein Pak 125 Colum and HPLC ion exchange chromatography on a TSK DEAE-5pw Column. The endoinulinase had a molecular weight of 72,000${\pm}$1,000 and was glycoprotein with 23 to 25% w/w sugar content. The enzyme was much more active on inulin with random cleavage mode than on sucrose and on palatinose: The ration of activity on inulin and sucrose (I/S ratio) was 10~14.

• 한국미생물·생명공학회지
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• 제30권4호
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• pp.305-311
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• 2002

Aspergillus ficuum 유래 acetyl xylan esterase(AXEase) 유전자(AXE)를 Pichia pastoris에서 과발현ㆍ분비 생산하기 위해 AOXI promoter와 mating factor $\alpha$-1 분비신호서열 하류에 AXE를 연결한 염색체 삽입 발현계(pPICZ$\alpha$C-AXE, 4.6 kb)를 구축하였다. 이것을 SacI으로 절단한 뒤 P. pastoris의 염색체 DNA 5'AOX1 부위에 삽입시켰다. 형질전환된 P. pastoris 균주를 메탄을 배지에서 플라스크 회분배양한 결과, 배양 36시간 때의 건조균체농도는 6 g-DCW/1, AXEase 총 발현량은 77 unit/ml이었다. 최적화된 methanol과 histidine 공급방법을 채용한 유가배양시 균체농도는 97 g-DCW/1, AXEase 총발현량은 930 unit/m1로 크게 증가하였다. 효소활성의 90% 이상은 배양 상등액에 존재하였으며, 상등액 단백질의 80%이상이 AXEase 단백질(33.5 kDa)였다. 이러한 결과는 9.8 g/l의 AXEase 단백질을 배양 상등액으로 대량 분비ㆍ생산할 수 있음을 의미한다.

• 한국임상수의학회지
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• 제18권1호
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• pp.18-21
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• 2001

In this study, we assessed the efficacy of a novel B. amyloliquefacience DS11 phytase (DS11 phytase) and that of a commercial Aspergillus ficcum phytase (AF phytase) through their bioavailabilities of phytin-posphorus and -calcium in the diet using cannulated pigs. For the purpose of evaluating the efficacy of the phytases in pigs, we determined phosphorous concentrations from serum and feces, in addition to ingesta obtained from the cannula at the terminal ileum. As results, phosphorus concentration was lower in feces from DS11 group and BASF group by 17% and 10%, and higher in serum from the respective groups by 34% and 20%, as compared to the control group. Both phytases are evaluated to enhance phosphorus availability to the great extent. Calcium concentration of feces were lower in DS11 group and BASF group by 31% and 10%, than that in the control. Calcium concentration of serum was higher in DS11 phytase group by 4% but lower in AF phyase group by 3%, then that in the control group.

• 한국미생물·생명공학회지
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• 제8권1호
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• pp.47-53
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• 1980

자연계로부터 구연산생성능이 강한 균주를 분리, 선정하여 동정한 결과는 다음과 같다. 1. Aspergillus 속에 속하는 균주 579주를 분리하여 각종 실험을 한 결과 표면배양으로는 분리균 M-80, M-315를, 야내배양으로는 M-315를 공식 균으로 선정하였다. 2. 선정균 M-80, M-315를 Raper등의 분류법에 따라 동정한 결과는 각각 Aspergillus usamii mut. shirousamii, Aspergillus ficuum으로 추정되었다. 3. 발육최적배지는 맥아즙한천배지였으며 M-315는 55$^{\circ}C$, M-80은 6$0^{\circ}C$에서 30분간 처리로서 각각 사멸되었고 생육PH는 대체로 PH3~6에서 양호하였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.153-156
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• 2000

1. A. ficuum의 genomic library 검색을 통해 Axe 유전자를 포함하고 있는 5.0 kb의 XbaI DNA 절편을 cloning 했다. Cloning 된 절편의 부분 염기서열 결정 결과 약 1.4 kb의 AXE coding 부위를 확인했으며, cDNA cloning과 그 염기서열의 결정을 통해 AXE coding 부위 내에는 두 개의 intron 이 존재함이 확인되었다. 2. AXE coding 부위의 아미노산 잔기 서열 검색 결과 A. awamori의 AXE와 약 92%의 상동성과 95%의 유사성이 있음이 확인 되었다. 3. 약 900 kb의 AXE의 cDNA를 yeast의 YEp352 vector의 GAL1 promoter의 전사 방향으로 cloning한 후 발현시킨 결과 형질전환체에서 acetyl esterase 활성을 확인했으며, 활성도는 숙주균주에 비해 약 4-5배의 높은 OD unit로 나타내는 것을 확인할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권5호
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• pp.673-680
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• 2000

An experiment was conducted with day-old 300 commercial male broiler chicks (Arbor Acres$^{(R)}$) to evaluate the efficacy of crude phytase preparerations produced from a culture of Aspergillus ficcum. The experiment consisted of five dietary treatments; T1, com-soy control diet with 0.45% non-phytate phosphorus (NPP) for starter period and 0.35% NPP for grower period; T2, control - 0.1% NPP; T3, control 0.2% NPP; T4, T3+600 U of crude phytase (broth+cell); and T5, T3+600 U of crude phytase (broth). The body weight gain, feed intake, and feed/gain of chickens fed T1 diet was highest (p<0.01) among treatments. BW gain and feed intake of T4 and T5 were greater than those of T3 but were less than those of T1 and T2. T3 was highest in mortality among treatments. Decreasing the NPP level lowered availability of DM, crude ash, ether extract, crude fiber, Zn, and Fe but supplementation of crude phytase preparations improved the availability of these nutrients as well as those of Ca, P and Cu. Excretion of P and Cu significantly decreased as the NPP level in the diet decreased. Further reduction of P and Cu excretion and reduction of Ca, Mg and Fe excretion were achieved by supplementation of crude phytase preparations. The serum concentrations of Ca, P, Mg, Zn, Fe, and Cu were significantly increased by crude phytase supplementation. The weight and length of tibia, and contents of crude ash, Ca, P, Mg, and Zn were adversely affected by lowering NPP level but partially recovered by supplementation of crude phytase preparations. In conclusion, lowering NPP level in the broiler diet significantly depressed the performance. Supplementation of crude phytase preparations produced from Aspergillus ficuum could partially recover the depression.

• KSBB Journal
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• 제13권3호
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• pp.284-288
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• 1998

Production of inulo-oligosaccharides from inulin was carried out with the maximum yield of 94% using a purified endoinulinase from Aspergillus ficcum. The optimum reaction temperature and pH were 55-60$^{\circ}C$ and pH 5.5-6.0, respectively. The Michaelis constant and maximum reaction velocity of the endoinuinase for inulin were 13.27 g/L and 0.13 g/L$.$min at 55$^{\circ}C$, pH 5.5, respectively. Inulin source had no significant effect on oligosaccharide yield and product composition, although initial production rate differed according to inulin origins. The reaction pH was a critical factor in inulo-oligosaccharide production because considerable free monosaccharides were released, decreasing oligosaccharide yield at low pH conditions. An empirical relationship describing the reaction performance was developed from kinetic data: the time to reach maximum oligosaccharide yield (tw) as a function of initial concentration of inulin (lo) and enzyme (Eo); i.e., log tM = -1.025 log Eo - 0.011 l0 + 2.655.