Bioremediation potential of genus Portulaca L. collected from industrial areas in Vadodara, Gujarat, India

During the present study, two species of Portulaca, i.e., P. tuberosa and P. oleracea were collected from two field sites in Vadodara, Gujarat, India; one irrigated with industrial effluent and other with tube well water, and were analyzed for heavy metal accumulation in different plant parts viz., roots, stem, leaves, and flowers. Plants collected from effluent irrigated areas showed high accumulation of all the investigated heavy metals in all plant parts with the maximum being in roots and the least in flowers. Interestingly, both species of Portulaca demonstrated hyperaccumulation of multiple elements viz., Cu, Ni, Hg, and Pb. The total shoot concentrations (mu g g(-1) dw) of Cu, Ni, Hg, and Pb in P. tuberosa were 1538, 1191, 789, and 2744, respectively, while in P. oleracea, these were 1940, 1542, 534, and 2312, respectively. Besides this, selective hyperaccumulation of Se (2,327 mu g g(-1) dw) and Al (1,164 mu g g(-1) dw) was shown by P. tuberosa and P. oleracea, respectively. Total shoot concentrations (mu g g(-1) dw) of Mo were about 399 and 668 in P. tuberosa and P. oleracea, respectively. Overall, P. oleracea accumulated higher amounts of multiple metals from industrial effluent contaminated site, hence appears to be a suitable candidate for phytoremediation purposes of metal contaminated areas.