诺氟沙星(Norfloxacin)对蛋白核小球藻(Chlorella pyrenoidosa)生长及抗氧化酶活性的影响

以蛋白核小球藻(Chlorella pyrenoidosa)为实验材料,研究了喹诺酮类药物诺氟沙星(Norfloxacin,NFLX)对小球藻生长及抗氧化酶活性的影响.结果表明,NFLX对小球藻的96hEC50为30.78mg·L-1,属于低毒.NFLX暴露对小球藻谷胱甘肽硫转移酶(GST)和过氧化氢酶(CAT)具有显著影响,当NFLX浓度高于30mg·L-1时,小球藻GST活性受到显著诱导,并随NFLX浓度增加而显著升高,而小球藻CAT活性随NFLX暴露浓度的升高表现出先诱导后抑制现象.NFLX对谷胱甘肽(GSH)和7-乙氧基-异吩唑酮-脱乙基酶(EROD)的影响较弱.在低浓度NFLX暴露下,GST和CAT可作为NFLX暴露的生物标记物.

Toxic Effects of Norfloxacin to the Growth and the Activity of Antioxidase of Chlorella pyrenoidosa

Chlorella pyrenoidosa was chosen as the test material to study the toxic effects of Norfloxacin on algae by acute toxicity test and a battery of biochemical parameters such as EROD, GST and CAT enzymes activities of algae in this research. The results showed that the 96h EC50 was 30.78mg·L-1 in NFLX exposure, NFLX was low-toxic to Chlorella pyrenoidosa. The activities of Glutathione S-transferase(GST) and catalase(CAT) had sensitive responses to the exposure of NFLX. CAT was induced at initial stages and inhibited gradually with the rising of NFLX concentration; while GST was induced significantly when exposed to over 30mg·L-1 NFLX and increased continuously with the rising of NFLX concentration. The activities of Glutathione(GSH) and 7-ethoxyresorufin-O-deethylase(EROD) had slight variances among different treatments groups. CAT and GST may act as the potential biomarkers of NFLX exposure at low concentration to Chlorella pyrenoidosa.