scholarly journals Microbial Transformations of Selenium Species of Relevance to Bioremediation

2016 ◽  
Vol 82 (16) ◽  
pp. 4848-4859 ◽  
Author(s):  
Abdurrahman S. Eswayah ◽  
Thomas J. Smith ◽  
Philip H. E. Gardiner
Keyword(s):  
Anthropogenic Activities ◽  
Anaerobic Respiration ◽  
Reaction Rates ◽  
Elemental Selenium ◽  
Human Beings ◽  
Microbial Transformations ◽  
Selenium Species ◽  
Number Of Microorganisms ◽  
Microbial Methylation ◽  
Detoxification Process

ABSTRACTSelenium species, particularly the oxyanions selenite (SeO32−) and selenate (SeO42−), are significant pollutants in the environment that leach from rocks and are released by anthropogenic activities. Selenium is also an essential micronutrient for organisms across the tree of life, including microorganisms and human beings, particularly because of its presence in the 21st genetically encoded amino acid, selenocysteine. Environmental microorganisms are known to be capable of a range of transformations of selenium species, including reduction, methylation, oxidation, and demethylation. Assimilatory reduction of selenium species is necessary for the synthesis of selenoproteins. Dissimilatory reduction of selenate is known to support the anaerobic respiration of a number of microorganisms, and the dissimilatory reduction of soluble selenate and selenite to nanoparticulate elemental selenium greatly reduces the toxicity and bioavailability of selenium and has a major role in bioremediation and potentially in the production of selenium nanospheres for technological applications. Also, microbial methylation after reduction of Se oxyanions is another potentially effective detoxification process if limitations with low reaction rates and capture of the volatile methylated selenium species can be overcome. This review discusses microbial transformations of different forms of Se in an environmental context, with special emphasis on bioremediation of Se pollution.

scholarly journals Utilization of Ostracods (Crustacea) as Bioindicator for Environmental Pollutants

2020 ◽  
pp. 73-93
Author(s):  
E. Parameswari ◽  
V. Davamani ◽  
R. Kalaiarasi ◽  
T. Ilakiya ◽  
S. Arulmani
Keyword(s):  
Industrial Development ◽  
Oil Spills ◽  
Human Impacts ◽  
Anthropogenic Activities ◽  
Environmental Pollutants ◽  
Chemical Properties ◽  
Agricultural Practices ◽  
Human Beings ◽  
Magnesium Calcite ◽  
Marine Areas

Ecosystem undergoes drastic changes due to the anthropogenic activities. As a consequence of industrial development, increasing population growth and modernized agricultural practices water resources like limnetic zone and marine areas have undergone eutrophication. This resulted in the decline in population of phytoplankton and zooplankton. Hence, it is an urgent need to monitor the quality of the environment. Several organisms are used as biomonitors. Among them, Ostracodes (Seed Shrimps) which belong to Crustacean group are very sensitive to those changes in the environment and useful in predicting the paleo environmental conditions. Ostracodes are bivalve arthropods which are enclosed in a carapace made of low magnesium calcite. These species are occurring for about 450 million years dates back to ordovician which are known for their easier fossilization. The development of Ostracodes is influenced by the physic - chemical properties of waters such as Salinity, temperature, pH, Dissolved oxygen, bottom grain sizes and sedimentation rates.  In addition to diversity and abundance of population, morphological and geochemical changes can also be detected in the Ostracod carapace (shell) which serves as a tracer of the water quality. These details are basis for utilizing Ostracods as paleoenvironmental (paleoclimatic, paleosalinity, paleooceanographic) reconstruction, ecotoxicity monitoring, biostratigraphic indicator. Moreover, these microcrustaceans showed similar or higher sensitivity to herbicides, pesticides, oil spills or heavy metals pollution other than traditional groups like copepods, protozoan, rotifers, cladocerans which are used to test the human impacts on ecosystem. These meiofaunas are highly adaptable to waters containing organic and inorganic contaminants generated by catastrophic activities by human beings in the surroundings.

scholarly journals Concentration of Aluminum in Drinking Water of Pakistan and Its Implications on Human Health

2020 ◽  
Vol 1 (2) ◽  
pp. 5
Author(s):  
Syeda Mehpara Farhat ◽  
Mahwish Ali
Keyword(s):  
Drinking Water ◽  
Human Health ◽  
Public Health Surveillance ◽  
Anthropogenic Activities ◽  
Extensive Literature ◽  
Average Risk ◽  
Human Beings ◽  
Surveillance Programs ◽  
Abundant Element ◽  
Great Exposure

Aluminum (Al), is the third most abundant element in the earth's crust but it is “excluded from biology” as development of all biota has taken place without it and there are no known biological functions linked to it. Currently anthropogenic activities have resulted in great exposure of this non-essential metal to human beings. The intake of Al has implications on human health and increases risk of various diseases. Major sources of Al include occupational exposure, food and water. Water is of greatest concern because Al is commonly bioavailable in water. The alarming situation in Pakistan about Al concentration in drinking water calls for an immediate need to design policies and legislations to ensure below average risk of this metal's effects. Limiting human exposure to Al is the only way to reduce the risk of developing neurodegenerative disorders like Alzheimer's disease (AD). In view of the extensive literature review, we propose development of public health surveillance programs for AI at the policy level.

scholarly journals Analysis of Pattern and Extent of Deforestation in Akure Forest Reserve, Ondo State, Nigeria

2019 ◽  
Vol 12 (1-2) ◽  
pp. 1-11
Author(s):  
Isaac Adelakun Gbiri ◽  
Nathaniel Olugbade Adeoye
Keyword(s):  
Anthropogenic Activities ◽  
Remote Sensing Data ◽  
Satellite System ◽  
Optical Remote Sensing ◽  
Human Beings ◽  
Southwestern Nigeria ◽  
Forest Reserve ◽  
Forest Depletion ◽  
Undisturbed Forest ◽  
The Government

Abstract Forest Reserves in Southwestern Nigeria have been threatened by urbanization and anthropogenic activities and the rate of deforestation is not known. This study examined the vegetation characteristics of Akure Forest Reserve using optical remote sensing data. It also assessed the changing pattern in the forest reserve between 1986 and 2017. Global Navigation Satellite System (GNSS) receiver was used to capture the location of the prominent settlements that surrounded the Forest Reserve in order to evaluate their effects on the forest. Landsat TM 1986, Landsat ETM+ 2002 and Landsat OLI_TIRS 2017 with 30m resolution were classified to assess the spatio-temporal changing pattern of the forest reserve. The results showed different composition of vegetation, which include undisturbed forest, secondary regrowth and farmlands. The study further revealed that in 1986, 2002 and 2017, undisturbed forest constituted 63.3%, 32.4% and 32.1% of the entire land area respectively, while secondary regrowth occupied 8.3% in 1986, 9.5% in 2002 and 15.6% in 2017. The farmlands had erratic growth between 1986 and 2017. It was 16.9% in 1986, 22.1% in 2002 and 17.5% in 2017. The bare ground exhibited inconsistency in the coverage. In 1986 the areal extent was 11.5%, when it increased to 36% in 2002 and decreased to 31.9% in 2017. In conclusion, the study revealed the extent of forest depletion at Akure Forest Reserve and it is therefore important that the residents, the government and the researchers show major concern about some of the critical factors to human beings that are responsible for forest depletion.

Enzymatic Treatment of Petroleum-Based Hydrocarbons

2018 ◽  
pp. 396-408
Author(s):  
Pankaj Kumar Chaurasia ◽  
Shashi Lata Bharati ◽  
Ashutosh Mani
Keyword(s):  
Aromatic Hydrocarbons ◽  
Daily Life ◽  
Refining Process ◽  
Enzymatic Treatment ◽  
Human Beings ◽  
Promising Technique ◽  
System Functioning ◽  
By Products ◽  
Detoxification Process ◽  
Microbial Sources

Petroleum and petroleum-based products are highly beneficial for our daily life system. Functioning of several industries and machineries directly depends on different forms of petroleum. There are strong possibilities of the release of such petroleum and petroleum-based compounds like aliphatic as well as aromatic hydrocarbons during their refining process, usage, storage, transport, and other activities due to the accidents, leakages, or just a little lack of awareness. Their exposure to soils or water causes serious problems for aquatic as well as human beings. The efficient removal or detoxification of such pollutants is the demand of the present time. The use of microbial sources for the bioremediation of such petroleum wastes may be promising technique because it does not require any drastic conditions for detoxification process and by-products produced by them are also harmless unlike chemical and other techniques. In this regard, this chapter discusses the enzymatic role in detoxification or bioremediation of petroleum-based hydrocarbons.

scholarly journals Identification of Anaerobic Selenate-Respiring Bacteria from Aquatic Sediments

2007 ◽  
Vol 73 (11) ◽  
pp. 3519-3527 ◽  
Author(s):  
Priya Narasingarao ◽  
Max M. Häggblom
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Anaerobic Respiration ◽  
Pseudomonas Stutzeri ◽  
Elemental Selenium ◽  
Rrna Gene ◽  
Terminal Electron Acceptor ◽  
Isolation And Characterization ◽  
Anaerobic Biotransformation ◽  
Gene Similarity

ABSTRACT The diversity population of microorganisms with the capability to use selenate as a terminal electron acceptor, reducing it to selenite and elemental selenium by the process known as dissimilatory selenate reduction, is largely unknown. The overall objective of this study was to gain an in-depth understanding of anaerobic biotransformation of selenium in the environment, particularly anaerobic respiration, and to characterize the microorganisms catalyzing this process. Here, we demonstrate the isolation and characterization of four novel anaerobic dissimilatory selenate-respiring bacteria enriched from a variety of sources, including sediments from three different water bodies in Chennai, India, and a tidal estuary in New Jersey. Strains S5 and S7 from India, strain KM from the Meadowlands, NJ, and strain pn1, categorized as a laboratory contaminant, were all phylogenetically distinct, belonging to various phyla in the bacterial domain. The 16S rRNA gene sequence shows that strain S5 constitutes a new genus belonging to Chrysiogenetes, while strain S7 belongs to the Deferribacteres, with greater than 98% 16S rRNA gene similarity to Geovibrio ferrireducens. Strain KM is related to Malonomonas rubra, Pelobacter acidigallici, and Desulfuromusa spp., with 96 to 97% 16S rRNA gene similarity. Strain pn1 is 99% similar to Pseudomonas stutzeri. Strains S5, S7, and KM are obligately anaerobic selenate-respiring microorganisms, while strain pn1 is facultatively anaerobic. Besides respiring selenate, all these strains also respire nitrate.

SYMPOSIUM ON CONGENITAL METABOLIC DISEASE

PEDIATRICS ◽  
1958 ◽  
Vol 21 (6) ◽  
pp. 1018-1021
Author(s):  
Charles U. Lowe ◽  
Barton Childs
Keyword(s):  
Gene Action ◽  
Genetic Material ◽  
Basic Mechanism ◽  
Reaction Rates ◽  
Human Beings ◽  
Secondary Effects ◽  
Genetic Origin ◽  
Daughter Cells ◽  
Metabolic Functions ◽  
Definition Of

MOST of the conditions to be considered in this symposium share one feature: their genetic origin. It could be profitable then to outline some of the principles of gene action and of the characteristics of genetic disease which will apply equally to all of the disorders to be reviewed. To begin, a definition of gene action is offered. This must be an empirical one since it is not known, with any precision, what a gene is. However, it is known that the genetic material provides the most basic mechanism for homeostasis, ensuring that offspring will exhibit the characteristics of the parent, whether the offspring be daughter cells or human beings. This is accomplished by means of control over the formation and design of the vital molecules of the organism; those molecules which in their turn control its intricate and interrealted metabolic functions. It is for the most part these metabolic functions which we attempt to measure in the elucidation of gene action in disease, and it will be seen in the ensuing discussions that only rarely is one able to make any direct assessment of the physicochemical properties of these molecules which bear a specific relationship to the gene. Much more commonly, a measurement is made of some form of activity of such substances, and a stepwise elucidation may be accomplished of the secondary effects which are consequent upon alterations in reaction rates or reaction failure. It is, in general, these secondary, tertiary, or consequential effects which are most easily measured, and which are the overt expressions of the disease. The principle illustrated here is, what a gene is said to do, depends upon which function we measure.

scholarly journals Bioremediation Options for Heavy Metal Pollution

2019 ◽  
Vol 9 (24) ◽  
pp. 191203 ◽  
Author(s):  
Meena Kapahi ◽  
Sarita Sachdeva
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Metal Pollution ◽  
Heavy Metal Pollution ◽  
Anthropogenic Activities ◽  
Environmental Pollutants ◽  
Human Beings ◽  
Heavy Metal Leaching ◽  
Advantages And Disadvantages ◽  
Financial Interests

Background. Rapid industrialization and anthropogenic activities such as the unmanaged use of agro-chemicals, fossil fuel burning and dumping of sewage sludge have caused soils and waterways to be severely contaminated with heavy metals. Heavy metals are non-biodegradable and persist in the environment. Hence, remediation is required to avoid heavy metal leaching or mobilization into environmental segments and to facilitate their extraction. Objectives. The present work briefly outlines the environmental occurrence of heavy metals and strategies for using microorganisms for bioremediation processes as reported in the scientific literature. Methods. Databases were searched from different libraries, including Google Scholar, Medline and Scopus. Observations across studies were then compared with the standards for discharge of environmental pollutants. Discussion. Bioremediation employs microorganisms for removing heavy metals. Microorganisms have adopted different mechanisms for bioremediation. These mechanisms are unique in their specific requirements, advantages, and disadvantages, the success of which depends chiefly upon the kind of organisms and the contaminants involved in the process. Conclusions. Heavy metal pollution creates environmental stress for human beings, plants, animals and other organisms. A complete understanding of the process and various alternatives for remediation at different steps is needed to ensure effective and economic processes. Competing interests. The authors declare no competing financial interests.

scholarly journals Biotransformation of Citrus Waste-II: Bio-Sorbent Materials for Removal of Dyes, Heavy Metals and Toxic Chemicals from Polluted Water

Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1544
Author(s):  
Neelima Mahato ◽  
Pooja Agarwal ◽  
Debananda Mohapatra ◽  
Mukty Sinha ◽  
Archana Dhyani ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Anthropogenic Activities ◽  
Industrial Effluents ◽  
Toxic Chemicals ◽  
Synthesis Process ◽  
Polluted Water ◽  
Waste Biomass ◽  
Human Beings ◽  
Valuable Compounds ◽  
Citrus Waste

Industrial processes and anthropogenic activities generate huge amounts of wastes in the form of chemicals, such as heavy metals, dyes, fertilizers, pharmaceutically active chemicals, battery effluents and so on. When these chemicals are left untreated and discarded in the ground or surface waters, they not only cause pollution and harm the ecosystem but also cause toxic effects on the health of human beings, animals and food crops. There are several methods of removal of these toxic materials from the wastewaters, and adsorption by bio-sorbents has been demonstrated as one of the most inexpensive, efficient and convenient methods. Citrus is one of the largest grown fruit crops in the tropical and subtropical regions on the planet. After processing of the fruits at food processing industries, approximately half of the fruit mass is discarded as waste, which causes a number of pollution problems. Alternately, this biomass can be converted to bio-sorbents for the removal of harmful and toxic chemicals from the industrial effluents and wastewaters. The first part of this article contains a thorough review on the biotransformation of citrus waste for the production of biofuel and valuable compounds by fermentation involving microorganisms. The second and concluding part reviews the recent progress in biotransformation of citrus waste biomass (that may be remaining post-extraction of valuable compounds/biofuel generation) into efficient adsorbent substrate materials and their adsorption capacities. The article also includes the details of the synthesis process and mechanisms of adsorption processes.

A Review on Measurement of Concentration of Heavy Metals in the Muscles of Mugil cephalus

2021 ◽  
Vol 43 (5) ◽  
pp. 611-611
Author(s):  
Fehmeeda Afzal Fehmeeda Afzal ◽  
Sonia Tariq Sonia Tariq ◽  
Ashraf Nadeem Ashraf Nadeem ◽  
Samiullah Samiullah ◽  
Jafar Iqbal Jafar Iqbal ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Food Chain ◽  
Industrial Waste ◽  
Anthropogenic Activities ◽  
Dry Weight ◽  
Important Class ◽  
Human Beings ◽  
Aquatic Life ◽  
Safe Limits

Heavy metals are an important class of compounds that is increasing in environment due to the anthropogenic activities. They are extremely toxic to human beings and animals. Many of them enter the water through industrial waste and effect the aquatic life. Fishes, for example, are an important source of food and they get effected by heavy metals when they ingest the infected sediments, mud and water. Heavy metals enter the food chain when infected fishes are consumed and effect humans as well. We highlight the recent (10-15 years) published work on measuring the levels of heavy metal in Mugilcephalus (Flathead mullet) fish. Out of all the methods compared and discussed in this paper, Atomic absorption spectroscopy was found to be the most preferred method and most commonly used by researchers because of its ease and cost. The most commonly used unit for metal detection in muscles was g/g (dry weight).The results also summarize advantages and drawbacks of methods used to digest muscles of the said species and heavy metal measurement. In selected studies, the levels of metals were also compared with the safe limits set by WHO, FAO and USEPA. This gives a lot of information about the edible fitness of the M.cephalus.

scholarly journals Effect of aluminum chloride against changes of the histological structure of the cerebral cortex of mice (swiss webster)

2021 ◽  
Vol 26 (2) ◽  
pp. 66-71
Author(s):  
Yulia Irnidayanti ◽  
Risa Eno Aprilyanti
Keyword(s):  
Heavy Metal ◽  
Cerebral Cortex ◽  
Aluminum Chloride ◽  
Urban Areas ◽  
Anthropogenic Activities ◽  
Histological Structure ◽  
Age Group ◽  
Human Beings ◽  
Health Security ◽  
Aluminum Exposure

The toxicity of metal to living organisms, including human beings, was discovered a long time ago. In the present time, aluminum exposure is widely used for wrapping food to keep it taste and smell. However it will affect to human health security, specially the brain. This study aimed to investigate the changes of histological Structure on the cerebral cortex caused by aluminum chloride. The mice were injected intraperitoneally with AlCl3 200 mg per kg body weight, once every 3 days, totalizing 10 administrations. Control only was administration distilled water. Histological observations were carried out using the paraffin method. The results of this study show that aluminum chloride cause disorganization of the laminated cerebral cortex, vacuolization, karyolysis, congestion, and hemorrhage. The mice of one and two-months of age group were more susceptible to aluminum chloride than the mice of the three-months of age group. This research can apply for an assessment of the exposure risk to heavy metal. Increasing Al contamination can occur naturally or by anthropogenic activities. The accumulation of the heavy metal in the organism can occur by biomagnification, by which heavy metal is passed from one trophic level to the next within a food web. Therefore communities that live in urban areas potentially exposed to metals aluminum and should be more concerned related to understanding health risks. Further studies are needed to examine the

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