Biofuel and bioremediation prospects of estuarine diatoms

Abstract

Escalating fuel prices, rising environmental concerns and dwindling stocks of fossil fuel have necessitated the exploration of viable alternative feedstocks. Biofuel from microalgae has been showing prospects of a viable alternative to conventional fossil fuels. The present study evaluates the bioremediation and biofuel potential of indigenously collected mixed consortia of estuarine diatoms, grown using aquaculture wastewater as the nutrient source. Diatoms, when subjected to different treatment conditions, exhibited better nutrients removal efficiencies (N: 89.1 ± 0.85%, P: 90.8 ± 0.12%) with significant variations in lipid content (14%-32%). Diatoms depicted real-time accumulation of neutral lipids during different phases of cell growth, observed through flow cytometry. Fatty acid profiling using GC-MS showed properties comparable to that of the plant-based oils. These results show the feasibility of growing diatoms in aquaculture wastewater and in vivo quantification of lipids using flow cytometry.