• Microbiology and Biotechnology Letters
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• v.6 no.2
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• pp.59-63
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• 1978

The Screening of fungi producing naringinase was done. A strain of Aspergillus midulans showed the highest naringinase activity among 447 strains those were isolated from soil, spoiled citrus friuts and stock cultures. The cultural Conditions of Asp. nidulans for production of naringinase were studied. A strain of Asp. nidulans showed higher activity when it was cultivated at 30$^{\circ}C$ for 3 days on wheat bran media supplemented with 2.0％ naringin, 0.2％ (NH$_4$)$_2$ SO$_4$ and 0.2％ CaCO$_3$.

• Microbiology and Biotechnology Letters
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• v.7 no.3
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• pp.141-147
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• 1979

Naringinase from Atpergillus nidulans was immobillized on DEAE-Sephadex A-25 and its characteristics were studied. The optimal conditions for the preparation of the immobilized enzyme were as follow; optimal pH, incubation time and the suitable amount of enzyme were 6.0, 30 min. and 110 units per gram of the dried ion exchage resin, respectively. The optimal pH of the immobilized enzyme was higher than that of the native enzyme. The optimal temperature increased from 4$0^{\circ}C$ to 5$0^{\circ}C$. The heat and pH stability of the immobillized enzyme were better than those of the native enzyme. No significant difference in the Michaelis constant was detected. Activation energy of the immobilized enzyme was 7.96 Kcal/mole, and the apparent Michaelis rate equation was used to describe the action of this material. The degree of hydrolysis was dependant on the flow rate at low rate of perfusion through the column. As the flow rate increased, the value of the apparent Km decreased.

• Microbiology and Biotechnology Letters
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• v.2 no.2
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• pp.111-117
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• 1974

Studies were carried out on the practical use of Naringinase and some chracteristics of Naringin solublizing enzme which might hydrolyae naringin to purunin. Obtained results were as follows. 1. Selected strain for Naringinase producing was identified to be Aspergillus niger S-1 and its naringinase was applied to chinese citron processing to remove the bitter taste. 2. Of the naringinase, naringin solubilizing enzyme was purified on a DEAE-Sephadex A-50 column and crystalized from acetone and ammonium sulfate. 3. Hydrolized naringin which has higher solubility rather than naringin or naringenin were identified by thin layer chromatography. 4. Hydrolyzed naringin and naringin were separatly determinated by ethylacetate extraction and this result was compared with sensory test.

• Food Science and Preservation
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• v.11 no.1
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• pp.53-56
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• 2004

The content of naringin and hesperidin of Yuzu were 95.54 and 103.99 in peel ; 65.77 and 77.18 in flesh ; 16.49 and 15.88mg％ in seed, respectively. When 10 mg％ of naringin and 5 mg％ hesperidin were treated with 10.0 units naringinase and 2.0 units of hesperidinase, they were decreased to 0.11 and 0.45 mg％, respectively. One percent of Japanese naringinase digested naringin and hesperidin that their final concentration were 0.54 and 0.09 mg％ in 30 minutes, while 5％ Amorepacific enzyme did until 0.26 and 0.04 mg％, respectively.

• Applied Biological Chemistry
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• v.13 no.3
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• pp.237-242
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• 1970

Fifty strains of mold which isolated from the various sources were screened for the production of Naringinase which hydrolyse naringin, the 7-rhamnoe-glucoside of 4'.5.7. - trihydroxyflavanonin, the main bitter principle of citrus fruits and grape fruits. Of the 4 strains yielded naringinase with significant activity, S-1 strain was selected on the criterion of industrial application, and some properties of crude naringinase of this S-1 was investigated. The results obtained were as follows. 1. Naringenase obtained from S-1 strain has optimum pH range from 3.0 to 5.0 for its activity. 2. Production of naringinase was increased on the addition of naringin to the medium. 3. Hydrolysis of naringin with approporiate concentration of naringinase was carried out linerly up to 80% on the 0.1% substrate solution. 4. The optimum temperature for its activity was $50^{\circ}C$, and this enzyme was inactivated 80% of its total activity at $70^{\circ}C$ for 10 minutes, 40% at $60^{\circ}C$ for 30 minutes. But signifiant decrease of activity were not occurred by heat treatment at $50^{\circ}C$ for 2 hours. 5. Crude enzyme of the naringinase obtained from S-1 strain was competitively inhibited by addition of glucose on the substrate, and inhibitor constant of the glucose on the this enzyme was 1.5 Mol, and inhibition rate were linearly increased according to the increase of sucrose concentration and 56% of its total activity was inhibited at 1 Mol sucrose solution.

• Korean Journal of Food Science and Technology
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• v.10 no.2
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• pp.209-214
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• 1978

Naringinase produced from Aspergillus nidulans was immobilized in acrylamide gel by the entrapping method and its characteristics were studied. Optimum acrylamide concentration was 10%, but N.N'-methylene bisacrylamide concentration had no influence on the final enzyme gel activity. The suitable amount of enzyme dissolved in the polymerization reaction mixture was 126 units/ml. Optimum pH of immobilized enzyme was 5.0 which was the same as that of free enzyme. However, immobilized enzyme showed a higher optumum reaction temperature, markedly increased pH and temperature stability. In a packed-column reactor, the observed reaction rate was increased proportionally to flow rate up to 5ml/min., but independent above 6ml/min.. Activation energy of the immobilized enzyme was 13.01 Kcal/mole, and the energy required for the thermal inactivation was 39.4 Kcal/mole. The apparent Km for 100 mesh gel was $7.23{\times}10^{-3}$ mole.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.04a
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• pp.96.2-96
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• 1978

Commerial naringinase from Aspergillus niger was partially purified by various methods, and was immobilized to porous alkylamine silica of 30~40 mesh and 400 $\AA\pm10％$ pore diameter that had been activated with 2.5％ glutaraldehyde. About 50~70％ of initial naringinase activity was recovered after the immobilization process. Some enzymatic properties of the immobilized naringinase was investigated and compared with those of the native enzyme. The optimal temper-ature had moved from $40^{\circ}C$ to $55^{\circ}C$ and the heat stability of the immobilized enzyme was better than that of the native naringinase. But no signi-ficant diference in the pH effect on activity was detected. The activation energy of reaction, Ea, was markedly decreased from 14.9 to 8.64 (Kcal/mole) by immobilization.

• Microbiology and Biotechnology Letters
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• v.6 no.2
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• pp.65-73
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• 1978

Naringinase extracted from the culture media of Aspergillus nidulans was purified, and the activity was proved to be stronger by 781 fold in the part of precipitation with ammonium sulfate, and column chromatography using DEAE-Sephadex A-25 and Sephadex G-100. Two fractions which had the same enzyme activity were isolated by the purification. Both fractions showed the highest enzymes activity under the reaction conditions of pH 5.0 and 40$^{\circ}C$. Molecular weight of fraction I and fraction II were estimated as 78,000 and 26,000 respectively. This indicated that fraction I would be trimer of fraction II. The enzyme was inhibited by glucose and rhammose, and the Km value was calculated to be 2.3${\times}$ 10$\^$-6/ g/ml.

• Korean Journal of Food Science and Technology
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• v.5 no.2
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• pp.78-83
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• 1973

The naringin hydrolyzing enzyme has been purified from the culture filtrate of the mold Aspergillus S-1 which selected to remove the bitter test of the orange or citrus fruits industrily. In a view of purity naringinase was more effectively purified in order of molecular sieving on Sephadeex G-200, starach gel electrophoresis, chromatography or a DEAE-Cellulose column and fractional precipitation by ammonium sulfate. The purified enzyme is homogeneous in paper electrophoresis from a culture filtrate by treatment fractional precipitation with ammonium sulfate, DEAE-Cellulose treatment and Sephadex-200 column chromatography and it hydrolyse only naringin to purunin.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.210.1-210
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• 1978

Aspergillus nidulans가 생산하는 naringinase를 ionic binding method 로써 DEAE-Sephadex A-25 를 사용하여 고정화시키는 조건과 그 고정화 효소의 성질에 대하여 검토하였다. 먼저 담체에 흡착되는 효소의 최적 pH는 6.0이었고 조제효소 110units 당 이상적인 담체량은 건조된 담체 1g이었다. 고정화 naringinase의 반응 최적 pH와 온도는 7.0과 5$0^{\circ}C$로서 native enzyme 보다 각각 높았다. 다음은 고정화 효소의 안정성에 미치는 pH와 온도의 영향으로서, pH 5에서 중성의 pH까지는 안정하였고 온도는 5$0^{\circ}C$까지는 안정하였으나 6$0^{\circ}C$ 이상에서는 뚜렷한 activity의 감소를 보였다.