논문 상세보기
pp.69-75
칡(Peuraria thunbergiana Bentham) 의 뿌리에서 추출한 조효소액을 황산암모늄으로 분획하고 이온교환 크로마트그래픽 및 겔여과에 의해 부분 정제하고 얻은 β-amylase의 효소학적 특성을 검토한 결과는 다음과 같다. 칡뿌리 β-amylase는 황산암모늄 0.4포화 이하의 획분에서 85% 이상의 활성을 나타내었으며, 가용성 전분을 기질로하여 maltose 를 생성하여 전형적인 β-amylase의 특성을 나타내었다. 또한 최적 pH, 최적 온도는 pH 6.0 및 50℃ 이었으며 pH 6.5∼7.0, 50℃이하에서 안정하였다. 기질농도에 대한 Km은 66.7mg% 이었으며 금속이온은 카드뮴, 알루미늄, 철, 은, 수은, 구리 등의 이온에 의해 효소활성이 저해되었다.
β-amylase(EC 3.2.1.2) was isolated from the root of arrowroot(Peuria thunbergiana Bentham) with distilled water and then fractionated with ammonium sulfate. Crude extract was partially purified by ion exchange chromatography and gel filtration. The enzymatic properties of partially purified β-amylase were as follows, the enzyme was fractionated with ammonium sulfate between 0.2 and 0.4 saturation, and showed the typical reaction properties of β-amylase producing only maltose from starch. Optinum pH and temperature were pH 6.5, 50℃ respectively. The activity of the enzyme had proportional relations with enzyme protein concentration below 4mg, and had Michaelis constant of 66.7mg% for soluble starch. The enzyme was inhibited by some metal ions such as silver, cadmium, mercury, aluminum iron and copper.
