磺胺嘧啶和盐酸四环素对四种赤潮藻生长的影响

Effects of sulfadimethoxine sodium and tetracycline hydrochloride on the growth of four red tide algae-Scrippsiella trochoidea,Karenia mikimotoi,Phaeocystis globosa and Skeletonema costatum

本文以锥状斯氏藻(Scrippsiella trochoidea)、米氏凯伦藻(Karenia mikimotoi)、球形棕囊藻(Phaeocystis globosa)、中肋骨条藻(Skeletonema costatum)为研究对象,实验室条件下对比研究了磺胺间二甲氧嘧啶钠(SMS)和盐酸四环素(TC)暴露下4种赤潮藻的细胞增长、光合色素组成以及最大光能转化效率(Fv/Fm)等的变化规律。研究结果表明:4种赤潮藻在SMS和TC(7.5~240 mg/L)暴露组细胞密度均未出现半抑制效应,SMS对4种赤潮藻细胞密度的最大抑制效应范围为5.47%~36.26%,略高于TC的最大抑制效应0~35.21%(球形棕囊藻无抑制效应);藻细胞叶绿素含量在抗生素暴露下均显著下降,但作为抗氧化剂和捕光色素的类胡萝卜素含量则显著增加;低浓度(<50 mg/L)TC暴露下,4种赤潮藻Fv/Fm均显著下降;TC(<30 mg/L)暴露下,4种赤潮藻细胞密度最大促进作用范围为11.30%~38.89%,球形棕囊藻细胞密度增加比例最高;赤潮藻对抗生素的响应存在显著的种间差别,两种抗生素暴露对球形棕囊藻生长的抑制效应明显低于其他3种赤潮藻,高浓度抗生素残留对浮游植物群落演替存在较强的干扰作用。

The effects of sulfadimethoxine sodium salt(SMS)and tetracycline hydrochloride(TC)on cell density,photosynthetic pigment and maximum photochemical efficiency(Fv/Fm)were studied with four red tide algae species Scrippsiella trochoidea,Karenia mikimotoi,Phaeocystis globosa and Skeletonema costatum.Concentrations of SMS and TC were 7.5 mg/L~240 mg/L in toxic tests.The results indicated that the maximum inhibitory rates of SMS on growth of four algae species were among 5.47%and 36.26%,while those of TC were among 0 and 35.21%.The growth inhibitory effect of TC on P.globosa was not observed in tested concentrations.The concentrations of photosynthetic pigment were influenced by two antibiotics.Concentrations of chlorophyll a and chlorophyll b in all algal species decreased significantly,while concentrations of carotenoids increased dramatically exposure to antibiotics.The maximum photochemical efficiencies of four algae decreased significantly exposure to TC at 50 mg/L,while no significant differences were detected in SMS treatments.The increases in cell density exposure to TC were detected in all algal species,with the highest ratios ranging from 11.30%to 38.89%.The growth stimulating effect of TC on P.globosa was much higher than those on other species.The toxicity effects of SMS and TC on P.globosa were much lower than those on other three algal species.High concentrations of antibiotics in wastewaters of aquaculture ponds,hospitals or pharmaceutical factories could influence the growth of algal species.The ecological risks of harmful algal bloom affected by antibiotics should be concerned in further study.