Citric acid enhanced phytoextraction of nickel (Ni) and alleviate Mentha piperita (L.) from Ni-induced physiological and biochemical damages

Abstract

Phytoremediation is considered one of the well-established and sustainable techniques for the removal of heavy metals and metalloids from contaminated sites. The metal extraction ability of the plants can be enhanced by using suitable organic materials in combination with metal-tolerant plants. This experiment was carried out to investigate the phytoextraction potential of Mentha piperita L. for nickel (Ni) with and without citric acid (CA) amendment in hydroponic experiment. The experiment was performed in controlled glass containers with continuous aeration in complete randomized design (CRD). Juvenile M. piperita plants were treated with different concentrations of Ni (100, 250, and 500 μM) alone and/or combined with CA (5 mM). After harvesting the plants, the morpho-physiological and biochemical attributes as well as Ni concentrations in different tissues of M. piperita plants were measured. Results revealed that Ni stress significantly decreased the plant agronomic traits, photosynthesis in comparison to control. Nickel stress enhanced the antioxidant enzymes activities and caused the production of reactive oxygen species (ROS) in M. piperita. The CA treatment under Ni stress significantly improved the plant morpho-physiological and biochemical characteristics when compared with Ni treatments alone. The results demonstrated that CA enhanced the Ni concentrations in roots, stems, and leaves up to 138.2%, 54.2%, and 38%, respectively, compared to Ni-only-treated plants. The improvement in plant growth with CA under Ni stress indicated that CA is beneficial for Ni phytoextraction by using tolerant plant species. Keywords Accumulation . Antioxidant enzymes . Citric acid . Mentha piperita . Nickel . Phytoremediation Significance of research work Reported results provided hopeful outcomes and sustainable fate of Ni phytoextraction. The present study confirmed the ecotoxicity of Ni in M. piperita and the efficacy of CA amendment to enhance the Ni bioavailability in culture media and to alleviate Ni-induced ecotoxicity. M. piperita significantly accumulate Ni under CA amendment as confirmed from the results.

Alterations in photosynthetic pigments, antioxidant machinery, essential oil constituents and growth of menthol mint (Mentha arvensis L.) upon nickel exposure

“…The reduction in the content of chlorophyll may be ascribed to the inhibition of chlorophyll biosynthesis by creating disparity in the plant nutrients (Molas 2002;Gautam and Pandey 2008) and due to destruction of pigments by increasing the activity of chlorophyll degrading enzyme chlorophyllase under stress conditions (Reddy 1986) and by inhibiting the enzymes responsible for chlorophyll biosynthesis such as protochlorophyll-dereductase and δ-aminolevulinic acid dehydratase (Kaveriammal and Subramami 2013;Younis et al 2015). Khair et al (2020) also reported similar findings on Ni toxicity in Mentha piperita. They observed that Ni caused alterations in antioxidant enzymes and physiological damage to the plants by generating reactive oxygen species (ROS).…”

Glutamic Acid-Assisted Phytomanagement of Chromium Contaminated Soil by Sunflower (Helianthus annuus L.): Morphophysiological and Biochemical Alterations

“…This suggests that plants with greater biomass, such as mustard, rapeseed, maize and sunflower plants, can be beneficial in the field and can survive in the presence of toxic heavy metals ( Cekic et al., 2017 ; Rizwan et al., 2017a ). Along with higher biomass plants, many vegetables, ornamental and floating plant species also showed greater accumulation potential ( Amir et al., 2020 ; Khair et al., 2020 ; Khalid et al., 2020 ) Phytoremediation refers to the use of plants for the extractive removal of metal contamination from soil and aquatic media. ( Salt et al., 1998 ; USEPA, 2000 ).…”

Microwave Irradiation and Glutamic Acid-Assisted Phytotreatment of Textile and Surgical Industrial Wastewater by Sorghum

“…Soil application of amino acids substantially increased sweet basil growth, including plant height and the leaf SPAD value of plant leaf extract, compared to unfertilized control plants [63]. Because of the reduction in ROS and EL production, the application of organic acid as a chelator raises the SPAD value and even the soluble protein value [64,65].…”