Purification of Acorn Tannin Hydrolyzing Enzyme of Aspergillus sp. AN-11 and Physiochemical Properties of It

Aspergillus sp. AN-11이 분비하는 도토리 Tannin 분해효소(分解酵素)의 정제(精製)와 물리화학적(物理化學的) 성질(性質)

  • Chae, Soo-Kyu (Department of Food Technology, Seoul College of Health) ;
  • Yu, Tai-Jong (Department of Food Technology, Korea University) ;
  • Kim, Byung-Mook (Department of Food Processing, Choongang University)
  • 채수규 (서울보건전문대학 식품가공과) ;
  • 유태종 (고려대학교 식품공학과) ;
  • 김병묵 (중앙대학교 식품가공학과)
  • Published : 1983.01.01

Abstract

Tannase of Aspergillus sp. AN-11 isolated from contaminated acorns was purified by a procedure involving ammonium sulfate precipitation, DEAE-cellulose column chromatography and Sephadex G-200 gel filtration. Physiochemical properties of the purified tannase was investigated. Tannase was purified about 37 folds with the yield of 49% from the culture broth of Aspergillus sp. AN-11. The purified tannase was homogeneous on polyacrylamide gel disc electrophoresis and was dissociable into two identical subunits on SDS-polyacrylamide gel electrophoresis. The molecular weight of the tannase was determined to be 200,000 by gel filtration on Sephadex G-200. The purified tannase showed a typical protein ultraviolet spectrum. The enzyme had a optimum pH 5.5 and optimum temperature at 30 to $40^{\circ}C$. The enzyme was stable at a pH range from 5.0 to 6.5 and at the temperature below $30^{\circ}C$. The enzyme was inactivated remarkably by $CuCl_2$ and $ZnCl_2. The Km value of the enzyme was $7.58{\times}10^{-4}\;M$.

도토리 부패물로부터 분리한 Aspergillus sp, AN-11 균주가 분비하는 tannase를 일련의 ammonium S-ulfate에 의한 침전, DEAE-Cellulose Column Chromatography 및 Sephadex G-200 gel filtration 방법에 의하여 정제하여 물리화학적 성질을 규명하였다. 정제된 tannase 는 비활성(比活性)이 조(粗)tannase에 비하여 37 배정도 증가되었으며, 효소활성이 회수(回收)는 약 49%이었다. 정제된 tannase 는 polyacrylamide gel 전기영동에 의한 균일성을 나타내었고, SDS-polyacrylamide gel 전기영동에서는 단일 밴드를 형성하는 두개의 동일한 subunits로 분리되었으며, 본 도토리 tannin 분해효소의 분자량은 200,000 정도로 계산되었다. 정제된 tannase는 전형적인 단백질 UV흡수 스펙트럼을 나타내었으며, 한편 최적 pH 몇 온도는 5.5 와 $30{\sim}40^{\circ}C$이었고 pH $5.0{\sim}6.5$와 온도 $30^{\circ}C$ 이하의 범위 내에서 비교적 안정성을 보였으며, $CuCl_2$$ZnCl_2금속염에 의해서는 효소활성이 크게 저해되었다. 또한 정제된 tannase의 Km 값은 $7.58{\times}10^{-4}M$이었다.

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