Bioremediation of domestic and industrial wastewaters integrated with enhanced biodiesel production using novel oleaginous microalgae

Abstract

The study illustrates the synergistic potential of novel microalgal, Chlamydomonas debaryana IITRIND3, for phycoremediation of domestic, sewage, paper mill and dairy wastewaters and then subsequent utilisation of its biomass for biodiesel production. Among these wastewaters, maximum lipid productivity (87.5 ± 2.3 mg L day) was obtained in dairy wastewater with removal efficiency of total nitrogen, total phosphorous, chemical oxygen demand and total organic carbon to be 87.56, 82.17, 78.57 and 85.97 %, respectively. Metal ions such as sodium, calcium, potassium and magnesium were also removed efficiently from the wastewaters tested. Pigment analysis revealed loss of chlorophyll a while increase in carotenoid content in algal cells cultivated in different wastewaters. Biochemical data of microalgae grown in different wastewaters showed reduction in protein content with an increase in carbohydrate and lipid contents. The major fatty acids in algal cells grown in dairy wastewater were C14:0, C16:0, C16:1, C18:0, C18:2 and C18:3. The physical properties of biodiesel derived from microalgae grown in dairy wastewater were in compliance with the ASTM D6751 and EN 14214 fuel standards and were comparable to plant oil methyl esters.

Insights into the Enhanced Lipid Production Characteristics of a Fresh Water Microalga under High Salinity Conditions

“…Nevertheless, the high cost associated with large scale production infers a long road ahead for their commercialization as sustainable biodiesel . To bridge this gap, various efforts are being made by using low cost feed stocks such as waste/sea waters, metobolically altered algal strains, enhancing lipid concentrations by using environmental stress factors etc. − Among those, bioprospecting of high TAG accumulating strains capable of growing in sea/waste waters is of central attention. The unique ability of microalgae to grow on such waters can reduce their dependence on fresh water reserves and nutrients, thus making the biodiesel production environmentally sustainable and economically viable .…”

Feasibility of Utilizing Wastewaters for Large-Scale Microalgal Cultivation and Biofuel Productions Using Hydrothermal Liquefaction Technique: A Comprehensive Review

“…The microalga Chlamydomonas debaryana IITRIND3 was successfully cultivated in different wastewaters from domestic, sewage, paper mills, and dairy wastewaters, respectively. The maximum biomass yield was depicted as 3.66 g L −1 in dairy wastewater whereas 3.56 g L −1 in domestic wastewater, respectively (Arora et al, 2016). Biomass yield found in this process by utilizing the wastewaters was quite productive, and the yield values are significantly higher than many other reports published till date.…”

Identification of Interacting Proteins of Transcription Factor DpAP2 Related to Carotenoid Biosynthesis From Marine Microalga Dunaliella parva

“…A comprehensive utilization of microalgae could significantly reduce the cost of microalgae biofuels, which included microalgae cultivation using wastewaters in outdoor raceway ponds (Arora et al, 2016;Gao et al, 2018;Keerthana et al, 2020) and the production of bioactive substances such as polysaccharides (Li et al, 2019), antiviral substances (Fritzsche et al, 2021), bioactive peptides (Donadio et al, 2021), and carotenoids (du Preez et al, 2021;Todorovićet al, 2021).…”