African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5210

Full Length Research Paper

Promotion effects of nitrogen on the cell proliferation of Platymonas subcordiformis evaluated by spectrophotography and cytometry analysis

Zhuo-Ping Cai1,2, Shun-Shan Duan2 and Hong-Hui Zhu1*  
1Guangdong Institute of Microbiology, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, State Key Laboratory of Applied Microbiology (Ministry-Guangdong Province Jointly Breeding Base), South China, Guangzhou 510070, China. 2Institute of Hydrobiology, Jinan University, Guangzhou 510632, China
Email: [email protected]

  •  Accepted: 08 February 2013
  •  Published: 26 February 2013


Platymonas subcordiformis, a model microalga in microalgal biotechnology, is rich in bioactive substances such as fatty acid, protein and vitamin, and hence it has been widely applied in biofuel, environmental purification, and pharmaceutical industry. In the current study, promotion effects of nitrogen on cell proliferation of P. subcordiformis were investigated by using spectrophotography ana-lysis and cytometry analysis, and the correlation between optical density at wavelength of 680 nm (OD680) and cell density was estimated. The results show that there were significant effects of nitrogen on the growth ofP. subcordiformis, with the OD680, cell density and dry weight increasing with the increase of nitrogen concentration. In the termination of experiment, OD680 values were 0.037, 0.111, 0.188, 0.393, 0.551 and 0.628; cell densities were 4×104, 2.6×105, 4.1×105, 8.3×105, 1.15×106 and 1.38×106 cells/mL; and dry weights were 0.021 7, 0.088 3, 0.131 7, 0.177 5, 0.238 3 and 0.310 0 g/L at the nitrogen concentrations of 0, 7.5, 15, 37.5, 75 and 150 mg/L, respectively. In addition, there was significantly positive correlation between OD680 and cell density throughout the experiment, with the regression equation of cell density (104 cells/mL) = 218.05OD680 - 1.6014 (R2 = 0.997 1) on day 11. The findings suggest that nitrogen promotes the cell growth and proliferation of P. subcordiformis, and that spectrophotography analysis is relatively simple, quick and accurate, which can be used in the scientific research or industrialization of this microalga.


Key words: Spectrophotography analysis, cytometry analysis, cell proliferation,Platymonas subcordiformis, nitrogen