TITLE:
Effect of Light Intensity and pH on Cell Density Assessed by Spectrophotometry for the Unicellular Algae Chlorella vulgaris
AUTHORS:
Nishat Tasnim, Debabrata Karmakar, Rakibul Hasan, Rashadul Islam, Saddam Hossain, Aftab Ali Shaikh, Rezaul Karim
KEYWORDS:
Chlorella vulgaris, Light Intensity, pH, Cell Density
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.14 No.4,
April
28,
2023
ABSTRACT: In this study, an effective environment for Chlorella vulgaris growth is sought after. As a substitute source of food and feed, increasing the
cell density of Chlorella culture is one of the keys to ensuring
sustainability. It can be showed from different studies that optimum
light intensity and pH could increase cell density. In this study, the effects
of light and pH on the growth rate of C. vulgaris were observed in
photobioreactor. A specific wavelength (682 nm) was determined by UV-Vis
Spectrophotometry to carry out the further analysis. The light intensities were
set at 7409, 9261 and 11,113 lux; pH values were set at 7, 8 and 9
respectively. The experimental results depicted the light intensity of 9261 lux as the best due to the higher number
of cells (48.56 × 106 cells/mL) obtained using this
intensity. In terms of pH, without pH control, cell numbers were found to be
highest under the light intensity of 9261 lux. When pH was controlled, it was
found that under the optimum light intensity, pH control between 7.0 and 7.5 was
the optimum range for the growth of C. vulgaris. Moreover, this method of study may possibly be a
promising source of low cost culture for Chlorella vulgaris.