title: Effects of aqueous stable fullerene nanocrystals (nC60) on the food conversion from Daphnia magna to Danio rerio in a simplified freshwater food chain.
abstract: Understanding the nanomaterial potential to the food conversion of two food chain levels is important in the ecosystem assessment as manufactured nanomaterials are being released into the environment. In this investigation, the food conversion from Daphnia magna (D. magna) (prey) to Danio rerio (D. rerio) (predator) was used as the study object of aqueous stable fullerene nanocrystals (nC60). Accumulated nC60 of D. magna was determined as the nominal initial exposure concentration for D. rerio. The results of 21-d dietary exposure experiment demonstrate that nC60 in D. magna decreased the body weight growths and condition factors of D. rerio, and reduced the food conversion ratio by 20% (from D. magna to D. rerio). Further, the experiments present that nC60 decrease three digestive enzymes activities of trypsinase, lipase, and amylase by 30, 29, and 55% in vivo, and by 60, 90, and 42% in vitro, respectively. Both in vivo and in vitro experiments indicated that nC60 was involved with the decrements of digestive enzymes activities. These decrements in digestive enzymes activities may be due to the deactivation caused by the adsorption of nC60 particles onto the surface or active center of digestive enzymes. Sum up, these results not only describe the nC60 deleterious effects on the food conversion from D. magna to D. rerio, but also provide some information regarding a probable food conversion inhibition mechanism of nC60.
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, 201306, China; School of Environmental Science and Technology, Shanghai Jiao Tong University, Shanghai, 200240, China. Electronic address: xjtao@shou.edu.cn.
authors.forename: Xianji
authors.initials: X
authors.lastname: Tao
authors.affiliation: College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, 201306, China.
authors.forename: Cuilan
authors.initials: C
authors.lastname: Li
authors.affiliation: School of Environmental Science and Technology, Shanghai Jiao Tong University, Shanghai, 200240, China; NUS Environmental Research Institute, Singapore.
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.affiliation: School of Environmental Science and Technology, Shanghai Jiao Tong University, Shanghai, 200240, China. Electronic address: ylhe@sjtu.edu.cn.
authors.forename: Yiliang
authors.initials: Y
authors.lastname: He
mesh_terms: D000681:Amylases / Q000378:metabolism; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D003621:Daphnia / Q000378:metabolism*; D004032:Diet; D020387:Food Chain; D005618:Fresh Water; D037741:Fullerenes / Q000633:toxicity*; D008049:Lipase / Q000378:metabolism; D053758:Nanoparticles / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015027:Zebrafish / Q000254:growth & development / Q000378:metabolism*
chemical_list: D037741:Fullerenes; D014874:Water Pollutants, Chemical; D008049:Lipase; D000681:Amylases
keywords: Aqueous stable fullerene; Dietary exposure; Food conversion; Inhibition mechanism