Investigating the productivity of biomass, lipid content, and biodiesel fuel in the mixed culture of Scenedesmus sp and Desmodesmus armatus microalgae.

Subject Areas : microalgae

Ammar Bagheri ¹ , Mohammad Gholami Parashkoohi ² , Ahmad Mohammadi ³ , Davood Mohammadzamani ⁴

1 - Department of Biosystem Mechanical Engineering. Takestan Branch. Islamic Azad university.
2 - Department of Biosystem Engineering, Takestan Branch, Islamic Azad University, Takestan, Iran
3 - Department of Bio-system mechanical, Arak branch, Islamic Azad University
4 - Department of Biosystem Mechanical Engineering. Takestan Branch. Islamic Azad university

Received: 2023-03-17 Accepted : 2023-05-22 Published : 2023-06-22

Keywords: Microalgae, Secondary metabolite, mixed culture, primary metabolite, pure culture,

Abstract :

The role of biotechnology in the production of primary and secondary metabolites of algae is of great importance. Cultivation of pure and single-celled algae has been widely carried out in recent years. Although mixed cultures of microalgae have advantages over pure cultures, there is still insufficient information on the performance of mixed cultures. In this research, all effective factors in the growth of two types of freshwater microalgae in mixed culture and their biological effects on the growth rate, biomass, and fat were investigated. The selected species included the microalgae Scenedesmus sp and Desmodesmus armatus. After the initial culture and reaching the appropriate density, the sample was transferred to the vertical photobioreactor and environmental factors were applied to the microalgae in pure and mixed cultures. Then the effect of environmental parameters and type of cultivation on biomass productivity and lipid content was investigated.The results showed that the highest amount of cell density and biomass in the conditions of a temperature of 25 degrees Celsius, the light intensity of 3000 lux, 16 hours of exposure, and acidity of 8 is related to the pure culture of Scenedesmus and then the mixed culture of Scenedesmus and Desmodesmus. The highest amount of lipid production under constant temperature conditions of 30°C, 18 hours of exposure, the light intensity of 4000 lux, and pH9 were related to Scenedesmus and then Desmodesmus. In terms of the amount of biodiesel produced, the highest amount was related to the microalgae Scenedesmus and then Desmodesmos under conditions of 16 hours of exposure, 4000 lux radiation, a temperature of 25°C, and pH8.The results showed that microalgae mixed culture had a positive effect on the production of biomass and cell density, and a negative effect on the production of secondary metabolites such as lipids, compared to pure culture.