The Effects of BDE-47、BDE-209on the Feeding Behavior with Brachionus Plicatilis and the Mechanism Based on the Changes of Digestive Enzyme Activity
|School||Ocean University of China|
|Keywords||PBDEs Brachionus plicatilis feeding feeding selectivity digestive enzyme activity|
A detail literature review of ecotoxicology effects of PBDEs on marineorganisms and use of rotifers in ecotoxicology were undertaken, and a series of indoorexperiments were conduced to investigate the effects of PBDEs on the lethaleffect,feeding and feeding selectivity, digestive enzyme activity with Brachionusplicatilis.The purposes were to observe the changes of two different aspects of thedigestion process(ingestion and digestive enzyme activity)under toxic stress,while toevaluate whether ingestion and digestive enzyme activity can be used as sublethalindicators in rapid toxicity tests.The results were summarized as follows:1、Ecotoxicology methods were used to study the acute toxicity of two PBDEswith Brachionus plicatilis.The acute lethality of these toxicants was studies to evaluate the sensitivity of the species and to establish the range of concentrations tobe used.The results showed that:(1) DMSO was the best dissolvent tested for BDE-47and BDE-209;(2) BDE-47and BDE-209had not the24h acute lethal effects onBrachionus plicatilis;(3) BDE-47and BDE-209had the24h acute immobilizationeffects on Brachionus plicatilis while the24hEC50of BDE-47was larger thanBDE-209which indicated that the toxicity of BDE-47was larger than BDE-209;(4)The external shape、interior structure and swimming behavior were changed underBDE-47and BDE-209stress.2、Ecotoxicology methods were used to study the feeding of Brachionus plicatilisunder the treatment of two PBDEs for4strains of microalgae,including Chlorellavulgaris Beij、Platymonas helgolandica Kylin var. tsingtaoensis、Isochrysis galbanaParke8701、Nitzschia closterium f. minutissima and and feeding selectivity for thebait mixture comprised of C. vulgaris, P. helgolandica, and N. closterium with theequaled biomass.The purposes were to evaluate the effects of two PBDEs on marineecological system,especially the effects on the marine graze food chain and the marineplankton biocoenosis structure.The results showed that:(1) Under the mono culture,F、G were all reduced with the time longed and the concentrations larged meanwhilethe good dose-effects relationship was presented;(2) Compared to G, F was the moresensitive indictor under feeding experiment;(3) Changes in the feeding behavior couldbe used as rapid indicators of toxic stress.(4) Under the mixed culture, F、G、Srandbiomass were all reduced with the time longed and the concentrations larged,meanwhile Si was curve.(5) In the feeding selectivity experiment, C. vulgaris was theoptimal food source for B. plicatilis under the toxic stress;(6) BDE-47was more toxicthan BDE-209on the feeding and feeding selectivity;(7) B. plicatilis had foodselectivity.3、Ecotoxicology methods were used to study the two PBDEs on the effects ofthree digestive enzyme included amylase、protease、lipase with B. plicatilis.Thepurposes were to futhermore study the effects on digestive process from thebiochemical aspects under PBDEs with B. plicatilis and whethere the digestiveenzyme activity were the alternative effect criteria for the short-term tests.The results showed that:(1) With the increase in the treatment time and the concentration, theinhibition of the digestive enzyme activity was more serious;(2) The effects of the twoPBDEs on the three digestive enzyme were different,and amylase> lipase>proteasewas presented;(3) Ingestion activity was more drastically reduced (at the sametoxicant concentrations) than the enzyme activity but the digestive enzyme activitywas a useful ecotoxicological endpoint in short-time assays.