Growth Aspects and Biochemical Composition of Synechococcus sp. MK568070 Cultured in Oil Refinery Wastewater

Abstract

The aim of the study was to explore the possibility of bioremediation of oil refinery wastewaters by the cyanobacterium Synechococcus sp. MK568070, isolated from the Adriatic Sea. The potential of biomass and lipid production was explored upon cultivation on oil refinery wastewater with excess CO2 after the removal of nutrients. The strain grew well in a wide range of salinities and ammonium concentrations, and was further tested on the wastewater from local oil refinery plant of various N-composition. Growth experiment under optimized conditions was used to analyze the lipid, carbohydrate and protein dynamics. The biomass yield was highly dependent on nutrient source and concentration, salinity and CO2 addition. Highest biomass yield was 767 mg/L of dry weight. Towards the end of the experiment the decline in carbohydrate to 18.9% is visible, whereas at the same point lipids, in particular saturated fatty acid methyl esters (FAME), started to accumulate within the cells. The content of lipids at the end of the experiment was 21.4%, with the unsaturation index 0.45 providing good biofuel feedstock characteristics. Fourier Transform Infrared (FTIR) spectroscopy analysis demonstrated a high degree of lipid accumulation in respect to proteins, along with the structural changes and biomass accumulation. In addition, the N-removal from the wastewater was >99% efficient. The potential of lipid accumulation, due to the functional photosynthesis even at the minimal cell quota of nutrients, is critical for the usage of excess industrial CO2 and its industrial transformation to biodiesel. These findings enable further considerations of Synechococcus sp. (MK568070) for the industrial scale biomass production and wastewater remediation.

Adriatic cyanobacteria potential for cogeneration biofuel production with oil refinery wastewater remediation

“…The experiments presented herein represent growth on wide range of NH 4 + , however under constant high salinity (38 psu) corresponding to Northern Adriatic. Previous research [72] demonstrated wide salinity tolerance of Synechococcus sp. MK568070.…”

Characterization of Pseudochloris wilhelmii potential for oil refinery wastewater remediation and valuable biomass cogeneration

“…Confidence intervals for biomass FIGURE 1 A scheme of 4 photobioreactors (PBR). Temperature, air/CO 2 bubbling, pH, light intensity and diurnal cycle are controlled by SCADA system (Blazǐna et al, 2019).…”

“…In addition to the high concentrations of ammonium, ORWW contains high concentrations of organic, and inorganic pollutants, such as petroleum hydrocarbons, mercaptans, polycyclic aromatic hydrocarbons (PAHs), benzene homologues, crude oil, heavy metals etc. (Jiang et al, 2010;Blazǐna et al, 2019).…”