- P-ISSN 1225-0163
- E-ISSN 2288-8985
Tyrosinase는 식물의 갈변현상에 관계가 있으며, 이의 방지를 위한 방법의 개발은 과학적인 관심사가 되고 있다. 솔잎으로부터 3개의 tyrosinase isozyme을 정제하여 그들의 활성에 영향을 주는 인자들을 분석하였다. L-ascorbic acid와 <TEX>${\beta}$</TEX>-mercaptoethanol은 효소의 활성을 크게 저해하였다. 또한 sodium diethyldithio-carbamate도 효소활성에 대한 경쟁적 저해제였으며, <TEX>$K_i$</TEX> 값은 <TEX>$P_1$</TEX>(0.030 mM), <TEX>$P_2$</TEX>(0.015 mM), <TEX>$P_3$</TEX>(0.019 mM)이였다. 반면 대부분의 금속이온들은 효소활성을 증가시켰다. L-DOPA를 기질로 사용했을 때 효소의 최적 pH는 9.0~9.5이며, 최적 온도는 <TEX>$55{\sim}60^{\circ}C$</TEX>를 나타내었다.
Tyrosinases are related to the enzymatic browning of plants and attract the major scientific interest for the prevention of it. Three tyrosinase isozymes (<TEX>$P_1$</TEX>, <TEX>$P_2$</TEX> and <TEX>$P_3$</TEX>) from pine needles were purified to homogeneity and characterized the factors that affect their activities. The L-ascorbic acid and <TEX>${\beta}$</TEX>-mercaptoethanol notably inhibited the enzymatic activities of the three isozymes. The sodium diethyldithiocarbamate was a competitive inhibitor of isozymes with the <TEX>$K_i$</TEX> values of <TEX>$P_1$</TEX>(0.030 mM), <TEX>$P_2$</TEX>(0.015 mM) and <TEX>$P_3$</TEX>(0.019 mM), respectively. Their enzyme activities were however, increased by the addition of most metal ions. The optimum pH for the three isozymes was 9.0~9.5 and the optimum temperatures ranged from 55 to <TEX>$60^{\circ}C$</TEX> using L-DOPA as substrate.