Heavy metal detoxification and tolerance mechanisms in plants: Implications for phytoremediation

2016 ◽  
Vol 24 (1) ◽  
pp. 39-51 ◽  
Author(s):  
Anamika Kushwaha ◽  
Radha Rani ◽  
Sanjay Kumar ◽  
Aishvarya Gautam
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Plant Cell Wall ◽  
Heavy Metal Stress ◽  
Heavy Metal Detoxification ◽  
Mycorrhizal Association ◽  
Copper Manganese ◽  
Living Organisms ◽  
Detoxification Mechanisms ◽  
Harmful Effects

Heavy metals, such as cobalt, copper, manganese, molybdenum, and zinc, are essential in trace amounts for growth by plants and other living organisms. However, in excessive amounts these heavy metals have deleterious effects. Like other organisms, plants possess a variety of detoxification mechanisms to counter the harmful effects of heavy metals. These include the restriction of heavy metals by mycorrhizal association, binding with plant cell wall and root excretions, metal efflux from the plasma membrane, metal chelation by phytochelatins and metallothioneins, and compartmentalization within the vacuole. Phytoremediation is an emerging technology that uses plants and their associated rhizospheric microorganisms to remove pollutants from contaminated sites. This technology is inexpensive, efficient, and ecofriendly. This review focuses on potential cellular and molecular adaptations by plants that are necessary to tolerate heavy metal stress.

A brief Survey of Assessment models to Predict stress Level of Heavy Metals in Soils

2020 ◽  
Vol 13 ◽  
Author(s):  
Sangeetha Annam ◽  
Anshu Singla
Keyword(s):  
Economic Growth ◽  
Heavy Metals ◽  
Heavy Metal ◽  
Ecological Risk ◽  
Stress Level ◽  
Metal Contamination ◽  
Heavy Metal Contamination ◽  
Human Life ◽  
High Stress ◽  
Heavy Metal Stress

Abstract: Soil is a major and important natural resource, which not only supports human life but also furnish commodities for ecological and economic growth. Ecological risk has posed a serious threat to the ecosystem by the degradation of soil. The high-stress level of heavy metals like chromium, copper, cadmium, etc. produce ecological risks which include: decrease in the fertility of the soil; reduction in crop yield & degradation of metabolism of living beings, and hence ecological health. The ecological risk associated, demands the assessment of heavy metal stress levels in soils. As the rate of stress level of heavy metals is exponentially increasing in recent times, it is apparent to assess or predict heavy metal contamination in soil. The assessment will help the concerned authorities to take corrective as well as preventive measures to enhance the ecological and hence economic growth. This study reviews the efficient assessment models to predict soil heavy metal contamination.

scholarly journals Kandungan Logam Berat Besi (Fe) Pada Air, Sedimen, Dan Kerang Hijau (Perna viridis) Di Perairan Tanjung Emas Semarang

2015 ◽  
Vol 18 (1) ◽  
Author(s):  
Endang Supriyantini ◽  
Hadi Endrawati
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Flow Velocity ◽  
Atomic Absorption ◽  
Key Words ◽  
Atomic Absorption Spectrophotometry ◽  
Pollution Level ◽  
Perna Viridis ◽  
Absorption Spectrophotometry ◽  
Living Organisms

Logam berat Fe merupakan logam berat essensial yang keberadaannya dalam jumlah tertentu sangat dibutuhkan oleh organisme hidup, namun dalam jumlah yang berlebih dapat menimbulkan efek racun.Penelitian ini bertujuan untuk menganalisis kandungan dan tingkat pencemaran logam berat Fe pada air, sedimen, dan kerang hijau (Perna viridis) di perairan Tanjung Emas Semarang. Penelitian ini dilaksanakan pada tanggal 7 November dan 7 Desember 2013 dengan metode penelitian deskriptif. Logam berat Fe dalam sampel air, sedimen dan kerang hijau dianalisis di Laboratorium Balai Besar Teknologi Pencegahan Pencemaran Industri (BTPPI) Semarang dengan menggunakan metode AAS (AtomicAbsorption Spectrophotometry). Hasil penelitian menunjukkan bahwa perairan Tanjung Emas masih dalam taraf terkontaminasi logam Fe. Sedangkan pada sedimen dan pada kerang hijau (Perna viridis) sudah terindikasi tercemar logam Fe.Meskipun demikian variasi faktor lingkungan seperti suhu, salinitas, pH, kecepatan arus dan jenis sedimen juga memberikan kontribusi yang cukup penting terhadap kandungan logam Fe.Kata Kunci: logam Fe, Air, Sedimen, Perna viridis, metode AAS Heavy metalsiron(Fe) is anessentialheavy metalswhose presencein a certain amountis neededby living organisms, but inexcessiveamountscan causetoxic effects.The aims of the research is to analyze the heavy metals coccentration and the pollution level of Fe in water, sediment, and green mussels (Perna viridis) at Tanjung Emas Semarang. This research was conducted from 7 November and 7 December 2013 using the Atomic Absorption Spectrophotometry (AAS) and research methodswithdescriptive. The results showed that the waters of the Tanjung Emas is still in the stage of heavy metals contaminated iron (Fe). Sediment and green mussels (Perna viridis)already indicated heavy metal contaminatediron. However, variations inenvironmental factorssuch astemperature, salinity, pH, flow velocity an dsediment types also providean important contributionto heavy metal contentof iron(Fe).Key Words: Fe, water, sediment, Perna viridis, metode AAS

scholarly journals Heavy Metals Removal from Water by Efficient Adsorbents

Water ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 2659
Author(s):  
Muhammad Zaim Anaqi Zaimee ◽  
Mohd Sani Sarjadi ◽  
Md Lutfor Rahman
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Water Treatment ◽  
Adsorption Process ◽  
Natural Occurrence ◽  
Toxic Heavy Metals ◽  
Major Purpose ◽  
Treatment Methods ◽  
Metals Removal ◽  
Harmful Effects

Natural occurrence and anthropogenic practices contribute to the release of pollutants, specifically heavy metals, in water over the years. Therefore, this leads to a demand of proper water treatment to minimize the harmful effects of the toxic heavy metals in water, so that a supply of clean water can be distributed into the environment or household. This review highlights several water treatment methods that can be used in removing heavy metal from water. Among various treatment methods, the adsorption process is considered as one of the highly effective treatments of heavy metals and the functionalization of adsorbents can fully enhance the adsorption process. Therefore, four classes of adsorbent sources are highlighted: polymeric, natural mineral, industrial by-product, and carbon nanomaterial adsorbent. The major purpose of this review is to gather up-to-date information on research and development on various adsorbents in the treatment of heavy metal from water by emphasizing the adsorption capability, effect of pH, isotherm and kinetic model, removal efficiency and the contact of time of every adsorbent.

scholarly journals Role of nitric oxide in plant responses to heavy metal stress: exogenous application versus endogenous production

2019 ◽  
Vol 70 (17) ◽  
pp. 4477-4488 ◽  
Author(s):  
Laura C Terrón-Camero ◽  
M Ángeles Peláez-Vico ◽  
Coral Del-Val ◽  
Luisa M Sandalio ◽  
María C Romero-Puertas
Keyword(s):  
Nitric Oxide ◽  
Heavy Metals ◽  
Heavy Metal ◽  
Human Health Risk ◽  
Heavy Metal Stress ◽  
Metal Stress ◽  
Future Research ◽  
Plant Responses ◽  
Research Perspectives

Abstract Anthropogenic activities, such as industrial processes, mining, and agriculture, lead to an increase in heavy metal concentrations in soil, water, and air. Given their stability in the environment, heavy metals are difficult to eliminate and can constitute a human health risk by entering the food chain through uptake by crop plants. An excess of heavy metals is toxic for plants, which have various mechanisms to prevent their accumulation. However, once metals enter the plant, oxidative damage sometimes occurs, which can lead to plant death. Initial production of nitric oxide (NO), which may play a role in plant perception, signalling, and stress acclimation, has been shown to protect against heavy metals. Very little is known about NO-dependent mechanisms downstream from signalling pathways in plant responses to heavy metal stress. In this review, using bioinformatic techniques, we analyse studies of the involvement of NO in plant responses to heavy metal stress, its possible role as a cytoprotective molecule, and its relationship with reactive oxygen species. Some conclusions are drawn and future research perspectives are outlined to further elucidate the signalling mechanisms underlying the role of NO in plant responses to heavy metal stress.

scholarly journals Glycine Betaine Accumulation, Significance and Interests for Heavy Metal Tolerance in Plants

Plants ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 896 ◽  
Author(s):  
Shafaqat Ali ◽  
Zohaib Abbas ◽  
Mahmoud F. Seleiman ◽  
Muhammad Rizwan ◽  
İlkay YAVAŞ ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Glycine Betaine ◽  
Metal Tolerance ◽  
Anthropogenic Activities ◽  
Heavy Metal Tolerance ◽  
Agricultural Practices ◽  
Effective Role ◽  
Living Organisms ◽  
Sustainable Agricultural Practices

Unexpected biomagnifications and bioaccumulation of heavy metals (HMs) in the surrounding environment has become a predicament for all living organisms together with plants. Excessive release of HMs from industrial discharge and other anthropogenic activities has threatened sustainable agricultural practices and limited the overall profitable yield of different plants species. Heavy metals at toxic levels interact with cellular molecules, leading towards the unnecessary generation of reactive oxygen species (ROS), restricting productivity and growth of the plants. The application of various osmoprotectants is a renowned approach to mitigate the harmful effects of HMs on plants. In this review, the effective role of glycine betaine (GB) in alleviation of HM stress is summarized. Glycine betaine is very important osmoregulator, and its level varies considerably among different plants. Application of GB on plants under HMs stress successfully improves growth, photosynthesis, antioxidant enzymes activities, nutrients uptake, and minimizes excessive heavy metal uptake and oxidative stress. Moreover, GB activates the adjustment of glutathione reductase (GR), ascorbic acid (AsA) and glutathione (GSH) contents in plants under HM stress. Excessive accumulation of GB through the utilization of a genetic engineering approach can successfully enhance tolerance against stress, which is considered an important feature that needs to be investigated in depth.

Overcoming the Bacteriostatic Effects of Heavy Metals on A. thiooxidans Direct Bioleaching of Saprolitic Ni Laterite Ores

2015 ◽  
Vol 1130 ◽  
pp. 263-267 ◽  
Author(s):  
Hee Chan Jang ◽  
Marjorie Valix
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Metal Tolerance ◽  
Heavy Metal Tolerance ◽  
Heavy Metal Stress ◽  
Lag Phase ◽  
Tolerance Index ◽  
Acid Generation ◽  
Laterite Ores ◽  
Laterite Ore

In this study, the adaptation of A. thiooxidans to heavy metals leached from saprolitic Ni laterite ores was performed by gradual acclimatisation. The bacteria was cultivated in heavy metals (Ni, Co, Fe, Mg, Cr and Mn) with total concentrations of 2400 to 24000 ppm equivalent to total dissolution of 1 to 10% (w/v) pulp densities of the saprolitic Ni laterite ore. Adaptation evolution mapped from its tolerance index was found to be dependent on metal concentration, acid generation, and period of adaptation. Bio-stimulation of cell growth and acid production was promoted by heavy metal stress on the bacteria. Pre-established heavy metal tolerance of the bacteria improved the leaching rate in its early phase; 20% and 7% increase in Ni and Co metal recoveries were observed in using adapted bacteria. However heavy metal tolerance was also achieved by the bacteria during the leaching process, albeit delayed by a lag phase. These results confirm the robust nature and suitability of A. thiooxidans in direct biomining of Ni ores.

scholarly journals Spatial Variations and Potential Risks of Heavy Metals in Seawater, Sediments, and Living Organisms in Jiuzhen Bay, China

2020 ◽  
Vol 2020 ◽  
pp. 1-13 ◽  
Author(s):  
Xia Sun ◽  
Bao-Shi Li ◽  
Xuan-Li Liu ◽  
Cheng-Xuan Li
Keyword(s):  
Heavy Metals ◽  
Risk Assessment ◽  
Heavy Metal ◽  
Ecological Risk ◽  
Potential Risk ◽  
Metal Pollution ◽  
Heavy Metal Pollution ◽  
Marine Ecology ◽  
Potential Risks ◽  
Living Organisms

Coastal waters are polluted by heavy metals to varying degrees, posing potential risks to marine ecology and human health. In May 2006, the pollution levels, sources, and ecological risks of heavy metals (Cu, Pb, Zn, Cd, Hg, and As) in seawater, surface sediments, and living organisms were studied in Jiuzhen Bay in Fujian, China. This study identified Hg (0.26–0.72 µg/L) and As (20.3–31.5 µg/L) pollution in the seawater of Jiuzhen Bay. In sediments, heavy Pb pollution (946 µg/g dw) was only detected at one station at a level posing very serious potential risk, while Hg pollution (0.052–0.087 µg/g dw) was observed at three stations at a level posing serious potential risk. No heavy metal pollution was detected in sediments at other stations. The concentrations of five heavy metals (Cu, Zn, As, Cd, and Pb) exceeded the corresponding National Quality Standards for oysters, indicating heavy pollution, based on an ecological risk assessment. In clams, two heavy metals (Pb and As) exceeded the standards, indicating light pollution, based on an ecological risk assessment. No heavy metal pollution was found in fish or shrimps. The heavy metals in the seawater and sediments of Jiuzhen Bay are mainly derived from the river discharges of Luxi and Wujiang Rivers although sewage discharge along the coast of Jiuzhen Bay is another source of heavy metal pollution at some stations. Given the pollution of Pb, Hg, and As in seawater and sediments at some stations within the bay, the potential risks of Pb, Hg, and As in living organisms to both the marine ecology and human health deserve increased attention.

scholarly journals Biomonitoring of Heavy Metal Pollution Using Acanthocephalans Parasite in Ecosystem: An Updated Overview

Animals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 811 ◽  
Author(s):  
El-Sayed E. Mehana ◽  
Asmaa F. Khafaga ◽  
Samar S. Elblehi ◽  
Mohamed E. Abd El-Hack ◽  
Mohammed A.E. Naiel ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Industrial Revolution ◽  
Heavy Metal Contamination ◽  
Developmental Stages ◽  
Heavy Metal Accumulation ◽  
Natural Ecosystem ◽  
Parasitic Infestation ◽  
Living Organisms ◽  
Life On Earth

As a result of the global industrial revolution, contamination of the ecosystem by heavy metals has given rise to one of the most important ecological and organismic problems, particularly human, early developmental stages of fish and animal life. The bioaccumulation of heavy metals in fish tissues can be influenced by several factors, including metal concentration, exposure time, method of metal ingestion and environmental conditions, such as water temperature. Upon recognizing the danger of contamination from heavy metals and the effects on the ecosystem that support life on earth, new ways of monitoring and controlling this pollution, besides the practical ones, had to be found. Diverse living organisms, such as insects, fish, planktons, livestock and bacteria can be used as bioindicators for monitoring the health of the natural ecosystem of the environment. Parasites have attracted intense interest from parasitic ecologists, because of the variety of different ways in which they respond to human activity contamination as prospective indices of environmental quality. Previous studies showed that fish intestinal helminths might consider potential bioindicators for heavy metal contamination in aquatic creatures. In particular, cestodes and acanthocephalans have an increased capacity to accumulate heavy metals, where, for example, metal concentrations in acanthocephalans were several thousand times higher than in host tissues. On the other hand, parasitic infestation in fish could induce significant damage to the physiologic and biochemical processes inside the fish body. It may encourage serious impairment to the physiologic and general health status of fish. Thus, this review aimed to highlight the role of heavy metal accumulation, fish histopathological signs and parasitic infestation in monitoring the ecosystem pollutions and their relationship with each other.

Sign in / Sign up

Export Citation Format

Share Document