Heavy Metal Tolerance in Metal Hyperaccumulator Plant, Salvinia natans

2013 ◽  
Vol 90 (6) ◽  
pp. 720-724 ◽  
Author(s):  
B. Dhir ◽  
S. Srivastava
2012 ◽  
Vol 610-613 ◽  
pp. 1223-1228 ◽  
Author(s):  
Su Chen ◽  
Lei Chao ◽  
Li Na Sun ◽  
Tie Heng Sun

In order to investigate the effects of four heavy metal tolerant microorganisms, Staphylococcus pasteuri (X1), Agrobacterium tumefaciens (X2), Penicillium chrysogenum (Z1) and Paecilomyces lavender (Z2), on heavy metals uptake by the heavy metal tolerance plant-maize and the cadmium hyperaccumulator plant-Beta vulgaris var. cicla L., a pot experiment with sediments was conducted. Through comparing the overall situations of four microorganisms’ role in enhancing maize and Beta vulgaris var. cicla L. to gather cadmium, lead, copper and zinc, plant biomasses, and enrichment characteristics, the combination of bacterium X2, fungus Z2 and these two plants can effectively repair these four heavy metals in sediments.


2013 ◽  
Vol 68 (8) ◽  
pp. 1795-1800 ◽  
Author(s):  
R. N. Tian ◽  
S. Yu ◽  
S. G. Wang ◽  
Y. Zhang ◽  
J. Y. Tang ◽  
...  

In this study, we report the tolerance and accumulation of Triarrhena sacchariflora to copper (Cu) and cadmium (Cd). The results show that T. sacchariflora had strong tolerance to Cu and Cd stress. The tolerance indexes (TI) were greater than 0.5 for all treatments. The bioconcentration factors (BCFs) to Cu and Cd were both above 1.0. The accumulation ability of roots was stronger than that of shoots, and ranges of BCF to Cu and Cd in roots were 37.89–79.08 and 83.96–300.57, respectively. However, the translocation ability to Cu and Cd was weak, with more than 86% of Cu or Cd accumulated in roots, suggesting an exclusion strategy for heavy metal tolerance. The uptake efficiency (UE) and translocation efficiency (TE) to Cu and Cd increased linearly as the Cu and Cd concentration in the substrate increased. UE was higher than TE, with a maximum of 2,118.90 μg g−1 root dry weight (DW) (50 mg L−1 Cu) and 1,847.51 μg g−1 root DW (20 mg L−1Cd), respectively. The results indicate that T. sacchariflora is a Cu- and Cd-tolerant non-hyperaccumulator plant, suggesting that T. sacchariflora could play an important role in phytoremediation in areas contaminated with Cu and Cd.


Author(s):  
Kashaf Junaid ◽  
Hasan Ejaz ◽  
Iram Asim ◽  
Sonia Younas ◽  
Humaira Yasmeen ◽  
...  

This study evaluates bacteriological profiles in ready-to-eat (RTE) foods and assesses antibiotic resistance, extended-spectrum β-lactamase (ESBL) production by gram-negative bacteria, and heavy metal tolerance. In total, 436 retail food samples were collected and cultured. The isolates were screened for ESBL production and molecular detection of ESBL-encoding genes. Furthermore, all isolates were evaluated for heavy metal tolerance. From 352 culture-positive samples, 406 g-negative bacteria were identified. Raw food samples were more often contaminated than refined food (84.71% vs. 76.32%). The predominant isolates were Klebsiella pneumoniae (n = 76), Enterobacter cloacae (n = 58), and Escherichia coli (n = 56). Overall, the percentage of ESBL producers was higher in raw food samples, although higher occurrences of ESBL-producing E. coli (p = 0.01) and Pseudomonas aeruginosa (p = 0.02) were observed in processed food samples. However, the prevalence of ESBL-producing Citrobacter freundii in raw food samples was high (p = 0.03). Among the isolates, 55% were blaCTX-M, 26% were blaSHV, and 19% were blaTEM. Notably, heavy metal resistance was highly prevalent in ESBL producers. These findings demonstrate that retail food samples are exposed to contaminants including antibiotics and heavy metals, endangering consumers.


Plants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 155
Author(s):  
Anastasia Giannakoula ◽  
Ioannis Therios ◽  
Christos Chatzissavvidis

Photosynthetic changes and antioxidant activity to oxidative stress were evaluated in sour orange (Citrus aurantium L.) leaves subjected to lead (Pb), copper (Cu) and also Pb + Cu toxicity treatments, in order to elucidate the mechanisms involved in heavy metal tolerance. The simultaneous effect of Pb− and Cu on growth, concentration of malondialdehyde (MDA), hydrogen peroxide (H2O2), chlorophylls, flavonoids, carotenoids, phenolics, chlorophyll fluorescence and photosynthetic parameters were examined in leaves of Citrus aurantium L. plants. Exogenous application of Pb and Cu resulted in an increase in leaf H2O2 and lipid peroxidation (MDA). Toxicity symptoms of both Pb and Cu treated plants were stunted growth and decreased pigments concentration. Furthermore, photosynthetic activity of treated plants exhibited a significant decline. The inhibition of growth in Pb and Cu-treated plants was accompanied by oxidative stress, as indicated by the enhanced lipid peroxidation and the high H2O2 concentration. Furthermore, antioxidants in citrus plants after exposure to high Pb and Cu concentrations were significantly increased compared to control and low Pb and Cu treatments. In conclusion, this study indicates that Pb and Cu promote lipid peroxidation, disrupt membrane integrity, reduces growth and photosynthesis and inhibit mineral nutrition. Considering the potential for adverse human health effects associated with high concentrations of Pb and Cu contained in edible parts of citrus plants the study signals that it is important to conduct further research into the accessibility and uptake of the tested heavy metals in the soil and whether they pose risks to humans.


BioMetals ◽  
2012 ◽  
Vol 25 (3) ◽  
pp. 489-505 ◽  
Author(s):  
Ganesh Thapa ◽  
Ayan Sadhukhan ◽  
Sanjib Kumar Panda ◽  
Lingaraj Sahoo

2013 ◽  
Vol 7 (2) ◽  
pp. 130-136 ◽  
Author(s):  
Tewari Suman ◽  
W Ramteke Pramod ◽  
Tripathi Manikant ◽  
Kumar Shailendra ◽  
Kumar Garg Satyendra

Author(s):  
Nasser Delangiz ◽  
Bahman Khoshru ◽  
Behnam Asgari Lajayer ◽  
Mansour Ghorbanpour ◽  
Solmaz Kazemalilou

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