Environmental Science and Pollution Research

, Volume 21, Issue 9, pp 6044–6056 | Cite as

Assessment of Jatropha curcas L. biodiesel seed cake toxicity using the zebrafish (Danio rerio) embryo toxicity (ZFET) test

  • Arnold V. HallareEmail author
  • Paulo Lorenzo S. Ruiz
  • J. C. Earl D. Cariño
Research Article


Consequent to the growing demand for alternative sources of energy, the seeds from Jatropha curcas remain to be the favorite for biodiesel production. However, a significant volume of the residual organic mass (seed cake) is produced during the extraction process, which raises concerns on safe waste disposal. In the present study, we assessed the toxicity of J. curcas seed cake using the zebrafish (Danio rerio) embryotoxicity test. Within 1-h post-fertilization (hpf), the fertilized eggs were exposed to five mass concentrations of J. curcas seed cake and were followed through 24, 48, and 72 hpf. Toxicity was evaluated based on lethal endpoints induced on zebrafish embryos namely egg coagulation, non-formation of somites, and non-detachment of tail. The lowest concentration tested, 1 g/L, was not able to elicit toxicity on embryos whereas 100 % mortality (based also on lethal endpoints) was recorded at the highest concentration at 2.15 g/L. The computed LC50 for the J. curcas seed cake was 1.61 g/L. No further increase in mortality was observed in the succeeding time points (48 and 72 hpf) indicating that J. curcas seed cake exerted acute toxicity on zebrafish embryos. Sublethal endpoints (yolk sac and pericardial edema) were noted at 72 hpf in zebrafish embryos exposed to higher concentrations. The observed lethal endpoints induced on zebrafish embryos were discussed in relation to the active principles, notably, phorbol esters that have remained in the seed cake even after extraction.


Zebrafish Danio rerio Embryotoxicity Jatropha curcas Phorbol esters Seed cake ZFET test 



The authors are grateful to the National Institute of Health (NIH) of the University of the Philippines Manila for the financial grant. Special thanks also go to Dr. Elisa Co and Asst. Prof. Kimberly Benjamin, who have given invaluable inputs and saw the study through its completion.


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© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Arnold V. Hallare
    • 1
    Email author
  • Paulo Lorenzo S. Ruiz
    • 1
  • J. C. Earl D. Cariño
    • 1
  1. 1.Department of Biology, CASUniversity of the PhilippinesManilaPhilippines

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