Biodegradation of naproxen by freshwater algae Cymbella sp. and Scenedesmus quadricauda and the comparative toxicity

Tengda Ding; Kunde Lin; Bo Yang; Mengting Yang; Juying Li; Wenying Li; Jay Gan

doi:10.1016/j.biortech.2017.04.018

Biodegradation of naproxen by freshwater algae Cymbella sp. and Scenedesmus quadricauda and the comparative toxicity

Bioresour Technol. 2017 Aug:238:164-173. doi: 10.1016/j.biortech.2017.04.018. Epub 2017 Apr 8.

Authors

Tengda Ding¹, Kunde Lin², Bo Yang³, Mengting Yang⁴, Juying Li⁵, Wenying Li⁶, Jay Gan⁷

Affiliations

¹ College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China; State Key Laboratory of Marine Environmental Science, Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen 361005, PR China.
² State Key Laboratory of Marine Environmental Science, Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, College of the Environment and Ecology, Xiamen University, Xiamen 361005, PR China.
³ College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China; Shenzhen Key Laboratory of Environmental Chemistry and Ecological Remediation, Shenzhen University, Shenzhen 518060, PR China.
⁴ College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China.
⁵ College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China; Shenzhen Key Laboratory of Environmental Chemistry and Ecological Remediation, Shenzhen University, Shenzhen 518060, PR China. Electronic address: jyli@szu.edu.cn.
⁶ Institute of Agricultural Resources & Environment, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, PR China.
⁷ Department of Environmental Sciences, University of California, Riverside, CA 92521, United States.

PMID: 28433904
DOI: 10.1016/j.biortech.2017.04.018

Abstract

Naproxen is one of the most prevalent pharmaceuticals and of great environment concern. Information about bioremediation of naproxen by algae remains limited and no study has been reported on the degradation mechanism and the toxicity of NPX on algae. In this study, both Cymbella sp. and Scenedesmus quadricauda showed complete growth inhibition (100%) at 100mgL^-1 within 24h. Biochemical characteristics including chlorophyll a, carotenoid contents and enzyme activities for these two microalgae were affected by NPX at relatively high concentrations after 4d of exposure. Degradation of naproxen was accelerated by both algae species. Cymbella sp. showed a more satisfactive effect in the bioremediation of NPX with higher removal efficiency. A total of 12 metabolites were identified by LC-MS/MS and the degradation pathways of naproxen in two algae were proposed. Hydroxylation, decarboxylation, demethylation, tyrosine conjunction and glucuronidation contributed to naproxen transformation in algal cells.

Keywords: Algae; Biodegradation; Degradation pathway; Naproxen; Toxicity.

MeSH terms

Chlorophyll
Chlorophyll A
Fresh Water
Naproxen / metabolism*
Scenedesmus*
Tandem Mass Spectrometry
Water Pollutants, Chemical / metabolism*
Water Purification

Substances

Water Pollutants, Chemical
Chlorophyll
Naproxen
Chlorophyll A