Naturally floating microalgal mat for in situ bioremediation and potential for biofuel production

Abstract

The objective of this study is to understand the fatty acid composition of a naturally floating microalgal mat with respect to seasonal variations in the water of a eutrophic lagoon on the west coast of India. The floating microalgal mat was explored for its bioaccumulation of metals and lipids for sustainable utilization in biofuel production. The effects of the nutrient profile and heavy metals in the water on the community composition of microalgal mat in different seasons were also studied and a principal component analysis was performed. It was observed that the unsaturated fatty acids such as C18:1n9c and C18:2n6c increased in low temperatures. The reverse effect was observed during the pre-monsoon season with augmented C16:0 fatty acid and an overall increment in saturated fatty acids. The Cyanophyceae and diatom community nurtured the growth during the pre-monsoon season by acquiring a higher bioaccumulation concentration factor (BCF) for Mn (3812.6 +/- 680), As (90.47 +/- 15.38), Ni (1620 +/- 163.64), Cr (73.27 +/- 21.23), and Cu (46.40 +/- 11.44). The higher abundance of Cyanophyceae in the microalgal mat exhibited better metal endurance during the pre-monsoon season, which could be obviously tilized for the bioremediation of heavy metals. The biodiesel prepared from the microalgal mat met European biodiesel standards. (C) 2015 Elsevier B.V. All rights reserved