Lead bioaccumulation in Acacia farnesiana and its effect on lipid peroxidation and glutathione production

Abstract

Phytoremediation offers a cheap, efficient and environmentally friendly option for cleaning sites contaminated with toxic elements. However, there is a need to find new plant species for phytoremediation and to understand the mechanisms involved in processes such as tolerance, accumulation, exclusion and metabolism of toxic metals in plants. Thereby, in this study, the ability of Acacia farnesiana (L.) Willd to tolerate and accumulate lead was analyzed. Seedlings grown in vitro with 250 and 500 mg Pb 2+ L −1 showed an increase in their growth, achieving tolerance indexes close to 100%. In seedlings exposed to 1,000 mg Pb 2+ L −1 , growth was strongly inhibited, finding an effective concentration 50% (EC 50 ) from 720 to 766 mg Pb 2+ L −1 . A. farnesiana accumulated ≥80% of the Pb 2+ in roots (up to 51,928 mgkg −1 of air-dried tissue) in seedlings exposed to 1,000 mg Pb 2+ L −1 , with high bioconcentration (>8.5) and low translocation (≤0.03) factors. These results indicate the suitability of A. farnesiana for lead-phytostabilization purposes. Lead concentrations below 500 mgL −1 had no significant effect on lipid peroxidation and enhanced the glutathione content, suggesting that the ability of A. farnesiana to withstand the Pb-induced oxidative stress could be related to glutathione metabolism.

Lipids and proteins—major targets of oxidative modifications in abiotic stressed plants

“…Increasing concentration of Fe (40, 80, and 160 mM) enhanced lipid peroxidation in Bacopa monnieri (Sinha and Basant 2009). Similarly, elevation in lipid peroxidation in a number of plants due to their exposure to Cu (Posmyk et al 2009;Opdenakker et al 2012;Singh et al 2012;Thounaojam et al 2012;Elleuch et al 2013;Ansari et al 2013a), Ni (Kazemi et al 2010;Gajewska et al 2012), Se (Malik et al 2012), As (Ansari et al 2013b), Pb (Qureshi et al 2007;Maldonado-Magaña et al 2011), Cr (Diwan et al 2008;2010), and some other heavy metals/metalloids was reported to be dependent on their doses and plant types (Sytar et al 2013). The main site of attack by any redox active metal in a plant cell is usually the cell membrane.…”

The Distribution of Lead Accumulation (Soil, Water and Mangrove Vegetation) to Conserve Segara Anakan Lagoon

“…TF is formulated by comparison between the accumulation of Pb of leaf and stem with root. If TF score > 1 gave indication that vegetation has high ability to absorb and translocate Pb contaminant (Maldonado-Magaña, 2011;Ahmadpour et al, 2012;Arifin et al, 2012;Branzini and Zubillaga, 2013;Madejon et al,2006;Ang et al,2010;Ashraf et al,2011;Madjid et al,2011;Maldonado-Magna, 2011). The accumulation of Pb in mangrove vegetation's also showed the positive correlation between the tolerance of mangrove vegetation with capacity to reduce impact of Pb pollution with precipitation, membrane filtration, electrolyte or liquid extraction, electro dialysis and reversed osmosis activity (Oo, et al, 2009).…”

Adaptability Study of Samama (Anthocephalus macrophyllus) on Several Lead (Pb) Level

“…Informasi tersebut merupakan hal yang paling penting dan strategis dalam rangka mendukung keberhasilan fitoremediasi melalui pengkayaan referensi jenis toleran dan mampu mengakumulasi Pb. Suatu studi menemukan bahwa semai Acacia farnesiana memiliki toleransi dan kemampuan hidup yang baik terhadap Pb hingga konsentrasi 500 mg/L (Magaña et al, 2010 …”

“…IT semai samama menurun pada penambahan Pb hingga konsentrasi 900 mg Pb/kg tailing, dimana IT mencapai nilai 170%. Magaña et al (2010) menemukan bahwa Acacia farnesiana memiliki IT yang sangat tinggi, yaitu > 100% pada pemaparan Pb sebesar 250 -500 mg/L, lalu mengalami penurunan menjadi < 75% ketika paparan Pb berada pada konsentrasi 750 mg/L.…”