Phytoremediation potential of Eichhornia crassipes for the treatment of<br>cadmium in relation with biochemical and water parameters

Abstract

The present investigation was aimed to assess the effect of cadmium chloride on some biochemical parameters and the potential of cadmium uptake of Eichhornia crassipes. The effects of increasing concentrations of cadmium chloride on growth characteristics of E. crassipes including root length, leaf area and biomass production was studied. The root growth of E. crassipes was severely affected at all concentrations of cadmium in the trays where plants were grown and in general it was serially increased. Similar trend was observed in average leaf area with 11.28 cm2 on 12th day in control while with only 7.05 cm2 at 75 ppm concentration. Chlorophyll contents were also observed to be decreased serially with the increasing concentrations of CdCl2. The lowest total chlorophylls were 118.56 mg/100g in comparison with 239.09 mg/100g in control set at the end of treatment. Polyphenol and proline contents were increased indicating the stress conditions due to toxicity of cadmium. Highest polyphenol and proline were 303.27 mg/100g and 8.14 mg/100g respectively at 50 ppm set of the treatment. Moreover, Electrical conductivity and total dissolved solids content of the various dilutions were decreased remarkably after 12 days of treatment. pH of the solution tend to become neutral while increase in turbidity might be related with root exudates and dead organics by the plants growing in the tray whereas decrease in hardness, acidity, sodium and potassium content was observed with increase in concentration. Values for BOD and COD were slightly increased at the end of treatment. Estimation of bioconcentration factor is very much important. It indicates that the species is more favourable to tolerate higher concentrations of heavy metals and also helps a lot in decontamination of the land, water etc. In this study increasing concentration of cadmium showed higher accumulation capacities and may be better treatment option for cadmium by means of phytoremediation

Phytoremediation potential of Bacopa monnieri in the removal of heavy metals

“…(El-Khatib, Hegazy and Abo-El-Kassem, 2014; Bokhari et al, 2016). Several studies have been previously conducted to study the toxic removal of B. monnieri grown in effluents and it has been found to be potential bioaccumulator of various pollutants (Borker et al, 2013;Badejo et al, 2015). In view of the above, main objectives of this study were to: (1) calculate the heavy metal accumulation by plant; (2) translocation and bioaccumulation factor of plant and 3interaction between contaminants and soil.…”

Metales pesados (Cd, Cr y Hg): su impacto en el ambiente y posibles estrategias biotecnológicas para su remediación

“…Las sales de cadmio son consideradas muy significativas en aguas contaminadas, no solamente por su alta toxicidad, sino por su habilidad para incorporarse en los alimentos, las plantas acuáticas y organismos mediante procesos naturales como bioacumulación y biomagnificación (Borker et al, 2013). Así mismo el Departamento de Servicios de Salud Humana de Estados Unidos propone que el cadmio sea considerado un compuesto carcinogénico (Waalkes, 2003).…”

“…Como regla general, los metales rápidamente biodisponibles para las plantas son Cd, Ni, Zn, As, Se y Cu, los moderadamente disponibles son Co, Mn y Fe; mientras que el Pb, Cr y Hg no son biodisponibles (Miller y Bassler, 2001). La habilidad de acumular metales pesados varía significativamente entre especies, cada una desarrolla diferentes mecanismos para transformar los iones, según sus características morfológicas, fisiológicas, genéticas y anatómicas (Borker et al, 2013;Swain et al, 2014).…”

“…En algunas zonas, la contaminación del suelo y agua por metales pesados o micronutrientes se encuentra en concentraciones fitotóxicas, lo que permite que algunas plantas puedan tener la capacidad de adaptarse y colonizar ambientes con altas concentraciones de metales pesados, hasta acumularlas en sus tejidos. Diferentes concentraciones de metales inducen diversas respuestas en las plantas, en los casos donde están expuestas a altas concentraciones, se genera inhibición de las enzimas involucradas en reacciones de fotosíntesis (Rascio y Navari-Izzob, 2011;Borker et al, 2013).…”

“…En la tabla 4 se presentan diferentes especies de plantas con la capacidad de resistir y transformar ciertos metales pesados. Cd, Cr, Hg Zhu et al, 1999;Dos Santos y Lenzi, 2000;Prasand y Freitas, 2003;January et al, 2008, Jafari, 2010Mane et al, 2011;Carrión et al, 2012, Kumar et al, 2012Saleth, 2012;Sood et al, 2012;Borker et al, 2013;Buta et al, 2014;Swain et al, 2014 Lemna minor L. Cd, Cr, Hg Prasand y Freitas, 200), Kumar et al, 2012;Bharti y Banerjee, 2013;Ücüncü et al, 2013Ücüncü et al, , Buta et al, 2014 Azolla pinnata Cd, Cr, Hg, Kumar et al, 2012, Bharti y Banerjee,2013 Tabla 4. Especies de plantas que pueden resistir y transformar Cd, Cr y Hg.…”