Influence of Walls in a Container on the Growth of the <i>Chlorella vulgaris</i> Algae

Abstract

Most of the algae are eukaryotic organisms commonly found in the aquatic environment. They are characterized by a great variety of species and the possibility of growing under various conditions. They photosynthesize, mainly needing light, water and carbon dioxide to grow. Algae can be used in various branches of the economy for the production of food, animal feed, bio-fertilizers, pigments, they can be used for sewage treatment or carbon dioxide sequestration. The aim of the work was to investigate the effect of the material from which the walls of containers are made on the bioreactors for algae cultivation. Two wall materials were used in the research: shiny aluminium foil and matte black light-absorbing paper. The content of photosynthetic pigments in algae cells, optical density, temperature and pH were examined. The tests were performed in triplicate and the standard error was calculated with the 95% confidence interval. It was observed that the glossy aluminium foil wall significantly improved the growth of the Chlorella vulgaris algae at the lowest light intensities by more than 4 times chlorophyll a compared to the sample placed in a container with walls of matte black paper. This means that the use of walls in shiny aluminium foil containers can reduce the lighting costs and contribute to an increase in the produced biomass.

Effect of Light Intensity and pH on Cell Density Assessed by Spectrophotometry for the Unicellular Algae &lt;i&gt;Chlorella vulgaris&lt;/i&gt;

“…Direct cell counts, measurements of the chlorophyll content, and absorbance can all be used to calculate the concentration of algae [16]. If cell concentration is to be obtained through spectrophotometry, then a wavelength of 750 nm is more preferable [17], although values of 665 nm, 680 nm are also used [18]. Typically, 680 nm is associated with chlorophyll absorption and has the possibility of interfering with results whereas 750 nm is above chlorophyll absorption [19].…”