Plants For Detoxification Research Articles

Microbiota analysis for risk assessment of xenobiotics: toxicomicrobiomics, incorporating the gut microbiome in the risk assessment of xenobiotics and identifying beneficial components for One Health.

This work explores three areas of relevance to the gut microbiome in the context of One Health; the incorporation of the microbiome in food safety risk assessment of xenobiotics; the identification and application of beneficial microbial components to various areas under One Health, and specifically, in the context of antimicrobial resistance. We conclude that, although challenging, focusing on the microbiota resilience, function and active components, are critical for advancing the incorporation of the gut microbiome in the risk assessment of xenobiotics. Moreover, research technologies, such as toxicomicrobiomics, culturomics and genomics, especially in combination, have revealed that the human microbiota may be a promising source of beneficial taxa or other components, with the potential to metabolise and biodegrade xenobiotics. These may have possible applications in several health areas, including in animals or plants for detoxification or in the environment for bioremediation. This approach would be of particular interest for antimicrobials, with the potential to ameliorate antimicrobial resistance development. Finally, we propose that the concept of resistance to xenobiotics in the context of the gut microbiome may deserve further investigation in the pursuit of holistically elucidating their involvement in the balance between health and disease.

Incorporating the Gut Microbiome in the Risk Assessment of Xenobiotics and Identifying Beneficial Components for One Health.

Three areas of relevance to the gut microbiome in the context of One Health were explored; the incorporation of the microbiome in food safety risk assessment of xenobiotics; the identification and application of beneficial microbial components to various areas under One Health, and; specifically, in the context of antimicrobial resistance. Although challenging, focusing on the microbiota resilience, function and active components is critical for advancing the incorporation of microbiome data in the risk assessment of xenobiotics. Moreover, the human microbiota may be a promising source of beneficial components, with the potential to metabolize xenobiotics. These may have possible applications in several areas, e.g., in animals or plants for detoxification or in the environment for biodegradation. This approach would be of particular interest for antimicrobials, with the potential to ameliorate antimicrobial resistance development. Finally, the concept of resistance to xenobiotics in the context of the gut microbiome may deserve further investigation.

Bioprospecting of Medicinal Plants for Detoxification of Aflatoxins

Aflatoxin contamination of foods is a major concern worldwide as aflatoxin B1 is implicated in the etiology of hepatic cancer in humans. The aflatoxins are a group of secondary metabolites mainly produced by Aspergillus flavus and Aspergillus parasiticus when they grow on a wide range of agricultural commodities. Once the food commodities are contaminated with aflatoxin, removal of the toxin is extremely difficult as the toxin is highly stable. Several approaches for detoxification of aflatoxins have been proposed; however, each method has its own shortcomings. Natural plant products are of interest as a source of safe and alternative way for detoxification of aflatoxins. This paper summarizes some of the recent developments in the detoxification of aflatoxins by using plant products.

Biogenic sulphide for cyanide recycle and copper recovery in gold–copper ore processing

Many complex-ore gold deposits with cyanide-soluble copper minerals such as chalcocite, covellite, bornite, cuprite, malachite and azurite are now being considered for processing. In some cases the ore is not currently being mined largely due to the various issues associated with the cyanide-soluble copper minerals in the ore, which results in low gold recoveries and high cyanide consumption and detoxification costs. Moreover, the presence of copper in tailings supernatant tends to stabilize weak-acid dissociable cyanide in a form toxic to wildlife. In the SART process (sulphidization–acidification–recycle–thickening), the cyanide associated with the copper cyanide complexes is released by NaHS dosing to precipitate copper and convert cyanide to HCN gas under weakly acidic conditions, allowing it to be recycled back to the leach process as free cyanide. Copper is also recovered as a valuable, high-grade (∼70% Cu) Cu 2S by-product. Cyanide recycling allows the leach circuit to be operated at higher cyanide levels, maximizing leach efficiency and minimizing copper deportment to gold electrowinning. The first commercial plant is at Telfer in Western Australia. Biogenically-produced hydrogen sulphide can be used to replace chemical sulphide at significantly lower cost and with the added advantage of lowering the acid demand substantially. While the capital cost of a biogenic SART plant will be higher than a cyanide detoxification plant, this will be more than offset by the revenues generated by copper recovery and the savings realized by cyanide recycle, allowing for a short payback time on the incremental capital. BioteQ is currently working with Columbia Metals Corporation Ltd., Canada, to apply its sulphide generating and precipitation technology in a SART circuit at both of Columbia’s gold projects (La Jojoba and Lluvia de Oro) in Northern Mexico. Processing of ores from both mines has presented challenges resulting from the presence of cyanide-soluble copper. This paper reviews the BioteQ biogenic SART process technology, economics and commercial status as well as environmental and operating outcomes.

The chemical form of trivalent chromium in xylem sap of maize (Zea mays L.)

The toxicity, mobility and bioavailability of Cr, a versatile industrial metal and a contaminant, depends on its chemical form, viz: Cr(lll) and Cr(VI). It may enter humans through plants grown on contaminated soil or irrigated by contaminated water. The phytoavailability and transfer through agricultural food chains requires an understanding of mechanisms of Cr uptake and translocation by plants. Xylem sap transports both nutrient and non-nutrient ions after absorption by roots to aerial parts of the plant. lt transports cations by complexation with organic ligands. Trivalent chromium, though prone to hydrolysis, also complexes O donor ligands. The chemical form in which Cr(lll) is transported by xylem sap was investigated. ln vitro studies were performed by mixing the xylem sap of maize plants at three stages of plant growth with radiotagged Cr(III). The speciation change was investigated after 10 days and 30 days by anion and cation exchange elution chromatography. The elution curves were compared with those of pure Cr(III) and Cr(III) complexes of different synthetic acids. Complexation of Cr(III) with ligands of xylem sap especially with carboxylates was evident. Cationic Cr(III) was vitally being transported as anionic organic complex species. The major species seemed to be that of Cr(III)-citrate. Citric acid was the major complexing acid of xylem sap as determined by HPLC. These mobile and soluble complexes may get immobilized and stored in leaves and other edible plant parts. This may also be a mechanism used by plants for detoxification of toxic Cr(VI) which may become reduced and then complexed.

PSA application for a PCB detoxification plant

Polychlorinated biphenyls (PCBs), a type of persistent organic pollutants (POPs), are considered to be endocrine disrupters. According to the Stockholm Convention on POPs, PCB detoxification is being accelerated globally. We have developed an environmentally sound chemical PCB detoxification plant using the ultraviolet ray/catalyst method. The purpose of this paper is to check the design methodology for the PCB detoxification plant by the application of probabilistic safety analysis. First, possible hazardous events were determined; second, the weakest points in these hazardous events were established; and third, the impact when failures arise at the weak points in the system were studied. We clarified the preventive measures as follows. To prevent PCBs leaking into the environment, select leak-tight valves for the piping containing PCBs, and reduce the number of valves. To prevent fire or explosions due to leaks of an inflammable mixture, select leak-tight valves, reduce the number of valves installed in the piping, and improve the reliability of the suppression tank in the isopropyl alcohol (IPA) recovery unit.

Basic Analysis on Severe Accidents for Chemical PCB Detoxification Plant Using the UV/Catalyst Method.

Implementation of polychlorinated biphenyls detoxification is being accelerated globally. We have developed an environmentally sound chemical polychlorinated biphenyls detoxification plant (codenamed: HMI), using the Ultraviolet ray (UV)/Catalyst Method. Safety analysis greatly facilitates communication on the subject of risk between the entity wishing to construct and operate the plant and the local residents. In the UVlCatalyst Method, PCB is mixed with sodium hydroxide (NaOH) and isopropyl alcohol (IPA: solvent) to realize PCB concentration in IPA of 1 wt% and subsequently PCB is dechlorinated by two independent process steps. The first step is the UV irradiating process (UV process), and the second step is the catalyst reaction process. As a result, biphenyl, NaOH, acetone, and water are generated after PCB is dechlorinated. A distilling column is designed in order to separate IPA from the solution, and IPA can be recycled many times as a solvent of PCB. IPA and acetone may form an inflammable mixture after leakage. Concerning HM1, first, hazardous events which produce severe accidents were identified by Failure Mode and Effect Analysis (FMEA); and secondly, leak of isopropyl alcohol (IPA), that causes fire/explosion, is defined as the most serious event. Based on this result, numerical safety analyses were carried out and the following findings were obtained. Thermal runaway experiment of residual liquid in the bottom of a distilling column: It was confirmed experimentally that no possibility of thermal runaway exists. Stress analysis of the distilling column after fire/explosion: The strength of the distilling column was proved. Impact evaluation concerning the surrounding facilities and residents after fire/explosion: It was confirmed that impact would be slight. Impact evaluation concerning exposure of residents to PCB: Exposure of residents to PCB would be negligibly small. In conclusion, the standardized methodologies for both safety evaluations and procedures concerning PCB plants were proposed and their validity verified.

Destruction of Low Levels of Volatile Organic Compounds in Dry Air Streams by an Electron-Beam Generated Plasma

The destruction of parts per million (ppm) levels of volatile organic compounds in a dry air stream by high–energy electron–beam irradiation has been investigated in a pilot plant at the University of Tennessee Space Institute, Tullahoma, Tennessee. In a series of experiments, dry air contaminated with various VOCs in the concentration range of 50–1000 ppm were treated in the UTSI pilot plant to determine the extent of destruction at various electronbeam dose levels. The destruction removal efficiency was determined as a function of the electron beam irradiation dose. The results suggest a charge transfer reaction as the major decomposition mechanism. A theoretical foundation of the process, along with a simple first–generation reaction kinetics model, a summary of the results from the pilot plant flow reactor, and a preliminary cost analysis for a fullscale detoxification plant using currently available electronbeam gun technology are presented in this paper.

Land Conservation Through Public/Private Partnerships

The International Trade In Toxic Waste: A Selected Bibliography Of Sources Deanna L. Lewis and Ron Chepesiuk Dacus Library, Winthrop University, Rock Hill, SC 29733, USA. TEL: 803-323-2131. Call it a toxic memorial, a monument to loose laws and fast money. This monument, tons of municipal incinerator ash from Philadelphia, lies on a rural Haitian beach where it was dumped one night in 1986 by a barge called the Khian Sea. The ship had entered the port with a permit to unload fertilizer. Fertilizer? Hardly! This cargo contained some of the most toxic chemicals on the planet--dioxins and furan and laced with heavy metals such as lead, cadmium, mercury and arsenic. As workers began heaping the ash only yards from the incoming waves, one crewman even stuffed his mouth with a handful of the flaky black cargo to prove its harmless nature. Nearly one fourth of the 13,000 plus tons of waste had been unloaded from the barge before the Haitian government intervened and ordered the ash reloaded onto the barge. But the Khian Sea disappeared under the cover of darkness, leaving approximately 3,000 tons of toxic ash on Haiti's beach. The Khian Sea returned to Philadelphia with the remainder of its deadly cargo. The ship spent the next two years vainly seeking a dumping ground; it crossed the Atlantic, sailed around the coast of West Africa, through the Mediterranean, down the Suez Canal and into the Indian Ocean. When it finally pulled into the Singapore harbor it had a new name (the Pelicano), a new owner, and an empty hull. No one is willing to take responsibility for this scandal. The city of Philadelphia blames the middleman who blames the barge owner. The owner claims the ash was still on board when the barge was sold. The tangled case went to court; finally in 1993, two executives of Coastal Carriers, operators of the Khian Sea, received modest fines and prison sentences for dumping in the ocean without a permit. The legal battle is not over yet. But how much longer will the ash sit on the beach, and who will remove it? While the Khian Sea incident is one of the most notorious episodes of the international toxic waste trade, it is by no means an isolated incident. In Koko, Nigeria, 3,800 tons of highly poisonous waste, including potentially lethal polychlorinated byphenyls (PCBs), were found in drums at an open site; they were dumped by a local businessman who forged his cargo papers and bribed Koko port officials. An American chemical company sold 3,000 tons of fertilizer to the Bangladesh government, but 1,000 tons of ash from copper smelting furnaces was mixed into the fertilizer before it was shipped. U.S. officials verified that this altered fertilizer contained dangerous levels of lead and cadmium. In another case, several hundred mysterious barrels washed up onto the Turkish shore. When curious locals opened some of the barrels, they suffered from nausea and skin rashes. A few barrels even exploded. In fact, countless barrels of trouble have rolled down the economic slope to a number of poor, less developed countries: black South Africa, the former East Germany, China, Romania, Poland, Thailand, the Ukraine, and others. The lure of foreign currency available in the international waste trade can be awfully tempting to cash-poor developing countries. In Papua New Guinea, for example, the government of the province of Oro negotiated a deal with a California firm to build a $38 million detoxification plant to process 600,000 metric tons of toxic waste a month. The deal, had it gone through, would have generated an income approximately six times the annual provincial budget.

Ferritin gene transcription is regulated by iron in soybean cell cultures.

Iron-regulated ferritin synthesis in animals is dominated by translational control of stored mRNA; iron-induced transcription of ferritin genes, when it occurs, changes the subunit composition of ferritin mRNA and protein and is coupled to translational control. Ferritins in plants and animals have evolved from a common progenitor, based on the similarity of protein sequence; however, sequence divergence occurs in the C termini; structure prediction suggests that plant ferritin has the E-helix, which, in horse ferritin, forms a large channel at the tetrameric interface. In contemporary plants, a transit peptide is encoded by ferritin mRNA to target the protein to plastids. Iron-regulated synthesis of ferritin in plants and animals appears to be very different since the 50- to 60-fold increases of ferritin protein, previously observed to be induced by iron in cultured soybean cells, is accompanied by an equivalent accumulation of hybridizable ferritin mRNA and by increased transcription of ferritin genes. Ferritin mRNA from iron-induced cells and the constitutive ferritin mRNA from soybean hypocotyls are identical. The iron-induced protein is translocated normally to plastids. Differences in animal ferritin structure coincide with the various iron storage functions (reserve for iron proteins and detoxification). In contrast, the constancy of structure of soybean ferritin, iron-induced and constitutive, coupled with the potential for vacuolar storage of excess iron in plants suggest that rapid synthesis of ferritin from a stored ferritin mRNA may not be needed in plants for detoxification of iron.