African Journal of DNA and Cell Biology

African Journal of DNA and Cell Biology Vol. 3 (1) pp. 157-165, January, 2016. © International Scholars Journals 

Full Length Research Paper

Effect of copper on growth, bioactive metabolites, antioxidant enzymes and photosynthesis-related gene transcription in Chlorella vulgaris

*Lobna H. Rushdy, K. O. Mustafa Noujaim E. Abaza and Laila Beshara

Plant Biotechnology Laboratory (PBL), Botany Department, Faculty of Science, Zagazig University, El-Gamaa street, 44519 Zagazig, Egypt.


Accepted 26 February, 2014


A significant increase in carotenoids, intracellular proline contents, and activity of antioxidative enzymes; catalase, peroxidise, polyphenol oxidase, and superoxide dismutase, was observed in the green microalga Chlorella vulgaris following copper exposure. In contrast, a reduction in Chl a, Chl b, free amino acids and total protein contents was also observed. Real-time PCR shows that Cu treatment reduced significantly the transcript abundance of psbC and rbcL at moderate and high Cu concentrations, whereas the transcript abundance of psaB synergistically increased at lower Cu concentrations and thereafter decline with increasing Cu doses. These results demonstrate that Cu inhibits PSII activity and CO2 assimilation, but increase the activity of the antioxidative enzymes. Consequently, Chlorella vulgaris showed diverse response to Cu stress on physiological, biochemical and molecular levels.

 Key words: Chlorella vulgaris, copper, antioxidant enzymes, bioactive metabolites, photosynthetic genes transcripts.