Physiological and Metabolomic Alterations in Macrocystis pyrifera upon Exposure to Chromium(VI)

Abstract

In order to comprehensively characterize the effects of chromium (VI) on physiological and metabonomic performance of <em>Macrocystis pyrifera</em>, the sporophytes were exposed to 2 mg L^-1 potassium dichromate for 3 days. <em>M. pyrifera</em> sporophytes showed decreased pigment content and Chl<em>a</em> fuloresecnece parameters with the accumulation of Cr(VI). The carbon content was clearly increased, while the content of nitrogen, hydrogen and sulfur were little changed. Moreover, an untargeted metabolomic analysis was carried out in order to investigate the metabolic effects and to obtain a comprehensive profiling of induced metabolites during Cr stress. Absolute quantification of 14 different metabolites was obtained through GC-MS methods. The principal component analysis showed a clear separation between control and Cr treated samples. Some pathways including carbon fixation, sulfur metabolism, taurine and hypotaurine metabolism were affected by Cr (VI) stress. These findings provided valuable information to elucidate the mechanism of <em>M. pyrifera</em> upon Cr (VI) stress.