外源酚对凤眼莲体内酚含量和与酚代谢有关酶的影响

凤眼莲能够吸收和在体内聚集外源苯酚，体内的酸含量随着环境中酚浓度的上升而上升。从生长于合酚培养液中的凤眼莲体内能够检测到酚糖苷，说明凤眼莲体内有酚精苷转移酶的存在。浓度小于５０ｍｇ／Ｌ的外源酚能提高凤眼莲体内的多酚氧化酶和过氧化物酶的活性。多酚氯化酶与过氧化物酶在线粒体和微粒体中均有不同程度的分布，而酚糖苷转移酶则不存在于这些细胞器中。

Effects of Exogenous Phenol on Phenol Content and the Enzymes Related to Phenol Metabolism in Eichhornia crassipes

Effects of exogenous phenol on phenol content, phenol glucosyltransferase (PGT) and the activities of polyphenol oxidase (PPO) and peroxidase (PO) in E. crassipes were studied. E. crassipes could absorb and concentrate exogenous phenolic compounds, and the content of phenol in the plant increased with its concentration in the medium (Fig. 3). Phenol,concentrations at up to 50 mg/L in the medium, increased the activities of polyphenol oxidase and peroxidase (Fig. 3). The peroxidase of the plant did not hydroxylate phenol to catechol (Fig. 2 ). Phenol glucosyltransferase was detected in E. crassipes for the first time (Fig. 1). The activities of the three enzymes studied were found to be different in mitochondria,microsomes and the remaining components (as supernatant) (Table 1). Quatitatively,phenol concentration in the medium had little effect on the activity of the phenol glucosyltransferase in the plant, but the method of its quantitative measurement needs further studies.