摘要
选取典型的持久性有机污染物全氟辛酸(PFOA)和雌二醇(E2),采用Kirk液体培养基对黄孢原毛平革菌(Phanerochaete chrysosporium,简称PC菌)纯培养的方式,以分光光度法测定了该体系中菌液总酶活性的变化规律,研究了PFOA和E2对其胞外过氧化物酶活性的影响。结果表明:(1)以"2,2-联氮基双(3-乙基苯并噻唑啉-6-磺酸)二铵盐"(ABTS)为底物,在pH为3的柠檬酸盐缓冲液中,依次加入ABTS、H2O2、MnSO4和菌液,在470nm处测定60s内反应的酶活性是其最大值,包含木质素过氧化物酶(LiP)、锰过氧化物酶(MnP)和漆酶(Lac)等胞外酶的总活性。(2)该培养体系中,PC菌分泌的胞外酶以LiP和MnP两种过氧化物酶为主,Lac活性极低;总酶活性随着培养时间的增加而增加,在第20～30d之间出现一次小高峰,50～60d之间出现一次大高峰,随后活性下降。(3)0.01mmol·L-1的全氟辛酸(PFOA)对这两种过氧化物酶(LiP和MnP)活性及菌液总酶活性的影响是一致的,表现为"先抑制,后促进"的作用;0.1μmol·L-1的雌二醇(E2)对其影响也是一致的,均表现为抑制作用。
Phanerochaete chrysosporium（PC） was pure cultured with Kirk liquid medium, two typical persistent organic pollutants perfluorooctanoic acid（PFOA） and estradiol（E2） were chosen, the effects of PFOA and E2 on PC extracellular peroxidase activity and total enzyme activities were studied. The results showed that 2, 2′-Azino-bis（3-ethylbenzothiazoline-6-sulfonic acid） diammonium salt（ABTS）was used as the substrate, and ABTS, H2O2, MnSO4, fungi solution were added in turn to citrate buffer with pH 3 to form a solution. The maximum bacterium activity was measured at 470 nm within 60 s reaction, which contained total activity of extracellular enzymes including lignin peroxidase（LiP）, manganese peroxidase（MnP）, laccase（Lac） and so on. Lip and MnP were two main extracellular enzymes secreted by PC in the culture system, while Lac enzyme activity was very low. Total enzyme activity increased with incubation time of PC. A small peak was observed between 20-30 days, while a big peak appeared between 50-60 days, and which decreased thereafter. Effects on activities of the two peroxidases（LiP and MnP） and total enzymes activities of broth were the same with addition of 0.01 mmol·L^-1 PFOA, which was inhibited at beginning and promoted later. Effects with addition of 0.1 mmol·L^-1 E2 on activities of the two peroxidases（LiP and MnP）and total enzyme activities of broth were the same, which executed consistent inhibition effects.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2013年第6期1134-1142,共9页
Journal of Agro-Environment Science
基金
国家自然科学基金项目(41201280)
2013年西北农林科技大学基本科研业务费专项资金项目(QN2013072)
