6-氨基青霉烷酸对布氏轮藻的毒性效应

Toxic Effect of 6-aminopenicillanic Acid on Chara braunii

采用水培法,研究6-氨基青霉烷酸(6-APA)溶液单一处理布氏轮藻(Chara braunii)的毒性效应。将布氏轮藻养于玻璃缸中,用水培法恢复其生长5 d后,进行质量浓度分别为20 mg/L、40 mg/L、60 mg/L、80 mg/L、100 mg/L的6-APA胁迫处理,7 d后,测定布氏轮藻的各项生理指标。研究结果表明,随着6-APA胁迫浓度的增大,布氏轮藻叶片相对电导率逐渐升高;布氏轮藻的丙二醛(MDA)含量变化幅度较大,呈先减少后增加态势;其超氧化物歧化酶(SOD)活性和过氧化氢酶(CAT)活性持续升高,而过氧化物酶(POD)活性先大幅升高后大幅下降;叶绿素含量呈先增加后减少的趋势。低浓度6-APA对布氏轮藻生长具有促进作用,高浓度6-APA抑制布氏轮藻生长,具有毒性效应。

The toxic effect of 6-Aminopenicillanic acid（6-APA） on Chara braunii was studied in this study.After a 5 days revival in the glass cylinders,6-APA concentrations were 20 mg/L,40 mg/L,60 mg/L,80 mg/L and 100 mg/L for 5 stress treatments,which were applied to water environment planted Chara braunii samples respectively for 7 days.Physiological indexes of Chara braunii under 5 treatments were measured and analyzed.The result showed that the relative electric conductivity of Chara braunii increased gradually with6-APA level rising;malondialdehyde content increased after an early decrease;activities of superoxide dismutase and catalase increased;the peroxidase activity had an significant early increase then decreased sharply;chlorophyll content decreased after an early increase.It is suggested that lower 6-APA concentration（less than 40 mg/L） could advance the growth of Chara braunii,while higher concentration（more than 60 mg/L） inhabited their growth,causing toxic effect.