RESEARCH ARTICLE Nopalea cochenillifera, a potential chromium (VI) hyperaccumulator plant Vinayak S. Adki & Jyoti P. Jadhav & Vishwas A. Bapat Received: 24 March 2012 / Accepted: 8 August 2012 / Published online: 23 August 2012 # Springer-Verlag 2012 Abstract Hexavalant chromium [Cr(VI)] tolerance and ac- cumulation in in vitro grown Nopalea cochenillifera Salm. Dyck. plants was investigated. A micropropagation protocol was establish for a rapid multiplication of N. cochenillifera and [Cr(VI)] tolerance and accumulation was studied in in vitro grown cultures. Cr concentration was estimated by atomic absorption spectroscopy in roots and shoots to con- firm plant’ s hyperaccumulation capacity. Plants showed tol- erance up to 100 μMK 2 Cr 2 O 7 without any significant changes in root growth after 16 days treatment; whereas, chlorophyll content in plants treated with 1 and 10 μM K 2 Cr 2 O 7 were not so different than the control plant. The levels of lipid peroxidation and protein oxidation increased significantly (p <0.01) with increasing concentration of chromium. Exposures of N. cochenillifera to lower concen- trations of K 2 Cr 2 O 7 (≤10 μM) induced catalase (CAT) and superoxide dismutase (SOD) significantly (p <0.001) but higher concentrations of K 2 Cr 2 O 7 (>100 μM) inhibited the activities of CAT and SOD. Roots accumulated a maximum of 25,263.396±1,722.672 mgCrKg -1 dry weight (DW); while the highest concentration of Cr in N. cochenillifera shoots was 705.714±32.324 mgCrKg -1 DW. N. cochenilli- fera could be a prospective hyperaccumulator plant of Cr (VI) and a promising candidate for phytoremediation purposes. Keywords Bioconcentration . Hexavalant chromium . Nopalea cochenillifera . Tolerance . Translocation . Hyperaccumulator Introduction Several industries release toxic substances, gases, and other harmful pollutants in the environment continuously affect- ing water sources and natural wealth posing serious health hazards. In this context, mainly hexavalent chromium [Cr (VI)] has been widely used in a wide range of industries, including electroplating, wood preservation, leather tanning, and alloy production (Yu et al. 2008). Disposal of these industrial wastes containing high levels of chromates results in anthropogenic contamination of pristine environments, in spite of the stringent industrial effluent standards. Chromium exists in a number of forms in natural environ- ment, among which Cr(VI) draws serious public health and legislative concerns because of its extremely high toxicity, mutagenicity and teratogenecity and has been listed as class A human carcinogens by the United States Environmental Protection Agency (Desai et al. 2008). Chromium oxyan- ions can readily permeate through biological membranes and their intracellular reduction results in the dire conse- quences of the chromate induced toxicity by generation of Cr(V), Cr(III) valence states, and reactive oxygen species that damage cellular components including DNA, proteins, and lipids (Rodriguez et al. 2011). Remediation of metal contamination is a challenging task, because unlike organic contaminants, metals cannot be degraded into non/less toxic components but needs re- moval. In attempting to preserve and conserve environment, new and traditional methods of remediation using physical, chemical, and biological principles have been studied (Agarwal et al. 2006). However, the physicochemical Responsible editor: Elena Maestri V. S. Adki : J. P. Jadhav : V. A. Bapat (*) Department of Biotechnology, Shivaji University, Vidyanagar, Kolhapur 416004, India e-mail: vabapat@gmail.com J. P. Jadhav Department of Biochemistry, Shivaji University, Kolhapur 416004, India Environ Sci Pollut Res (2013) 20:1173–1180 DOI 10.1007/s11356-012-1125-4