The oligodynamic effect (from Greek oligos, "few", and dynamis, "force") is a biocidal effect of metals, especially heavy metals, that occurs even in low concentrations. This effect is attributed to the antibacterial behavior of metal ions, which are absorbed by bacteria upon contact and damage their cell membranes. [1]
In modern times, the effect was observed by Carl Nägeli, although he did not identify the cause. [2] Brass doorknobs, brass handrails, and silverware all exhibit this effect to an extent.
The metals react with thiol (-SH) or amine (-NH(1,2,3)) groups of proteins, a mode of action to which microorganisms may develop resistance. Such resistance may be transmitted by plasmids. [3]
Aluminium has been found to compete with iron and magnesium and bind to DNA, membranes, or cell walls, leading to its toxic effect on microbes, such as cyanobacteria, soil bacteria and mycorrhizal fungi. [4]
Aluminium triacetate (Burow's solution) is used as an astringent mild antiseptic. [5]
Orthoesters of diarylstibinic acids are fungicides and bactericides, used in paints, plastics, and fibers. [6] Trivalent organic antimony was used in therapy for schistosomiasis. [7]
For many decades, arsenic was used medicinally to treat syphilis. It is still used in sheep dips, rat poisons, wood preservatives, weed killers, and other pesticides. Arsenic is poisonous if it enters the human body. [8]
Barium polysulfide is a fungicide and acaricide used in fruit and grape growing. [9]
Bismuth compounds have been used because of their astringent, antiphlogistic, bacteriostatic, and disinfecting actions. In dermatology bismuth subgallate is still used in vulnerary salves and powders as well as in antimycotics. [10] In the past, bismuth has also been used to treat syphilis and malaria. [11]
Boric acid esters derived from glycols (example, organo-borate formulation, Biobor JF) are being used for the control of microorganisms in fuel systems containing water. [12]
Brass vessels release a small amount of copper ions into stored water, thus killing fecal bacterial counts as high as 1 million bacteria per milliliter. [13]
Copper sulfate mixed with lime (Bordeaux mixture) is used as a fungicide and antihelminthic. [14] Copper sulfate is used chiefly to destroy green algae (algicide) that grow in reservoirs, stock ponds, swimming pools, and fish tanks. Copper 8-hydroxyquinoline is sometimes included in paint to prevent mildew. [15]
Paint containing copper is used on boat bottoms to prevent barnacle growth (biofouling).
Copper also has the ability to destroy viruses, such as influenza viruses, noroviruses or human immunodeficiency virus (HIV). [16]
Gold is used in dental inlays and inhibits the growth of bacteria. [17]
Physicians prescribed various forms of lead to heal ailments ranging from constipation to infectious diseases such as the plague. Lead was also used to preserve or sweeten wine. [18] Lead arsenate is used in insecticides and herbicides. [19] Some organic lead compounds are used as industrial biocides: thiomethyl triphenyllead is used as an antifungal agent, cotton preservative, and lubricant additive; thiopropyl triphenyllead as a rodent repellant; tributyllead acetate as a wood and cotton preservative; tributyllead imidazole as a lubricant additive and cotton preservative. [20]
Phenylmercuric borate and acetate were used for disinfecting mucous membranes at an effective concentration of 0.07% in aqueous solutions. Due to toxicological and ecotoxicological reasons phenylmercury salts are no longer in use. However, some surgeons use mercurochrome despite toxicological objections. [3] Mercurochrome is still available to purchase in Australia to use on minor wounds. Dental amalgam used in fillings inhibits bacterial reproduction. [13]
Organic mercury compounds have been used as topical disinfectants (thimerosal, nitromersol, and merbromin) and preservatives in medical preparations (thimerosal) and grain products (both methyl and ethyl mercurials). Mercury was used in the treatment of syphilis. Calomel was commonly used in infant teething powders in the 1930s and 1940s. Mercurials are also used agriculturally as insecticides and fungicides. [21]
The toxicity of nickel to bacteria, yeasts, and fungi differs considerably. [22]
The metabolism of bacteria is adversely affected by silver ions at concentrations of 0.01–0.1 mg/L. Therefore, even less soluble silver compounds, such as silver chloride, also act as bactericides or germicides, but not the much less soluble silver sulfide. In the presence of atmospheric oxygen, metallic silver also has a bactericidal effect due to the formation of silver oxide, which is soluble enough to cause it. Even objects with a solid silver surface (e.g., table silver, silver coins, or silver foil) have a bactericidal effect. Silver drinking vessels were carried by military commanders on expeditions for protection against disease. It was once common to place silver foil or even silver coins on wounds for the same reason. [23]
Silver sulfadiazine is used as an antiseptic ointment for extensive burns. An equilibrium dispersion of colloidal silver with dissolved silver ions can be used to purify drinking water at sea. [3] Silver is incorporated into medical implants and devices such as catheters. Surfacine (silver iodide) is a relatively new antimicrobial for application to surfaces. Silver-impregnated wound dressings have proven especially useful against antibiotic-resistant bacteria. Silver nitrate is used as a hemostatic, antiseptic and astringent. At one time, many states[ clarification needed ] required that the eyes of newborns be treated with a few drops of silver nitrate to guard against an infection of the eyes called gonorrheal neonatal ophthalmia, which the infants might have contracted as they passed through the birth canal. Silver ions are increasingly incorporated into many hard surfaces, such as plastics and steel, as a way to control microbial growth on items such as toilet seats, stethoscopes, and even refrigerator doors. Among the newer products being sold are plastic food containers infused with silver nanoparticles, which are intended to keep food fresher, and silver-infused athletic shirts and socks, which claim to minimize odors. [15] [17]
Thallium compounds such as thallium sulfate have been used for impregnating wood and leather to kill fungal spores and bacteria, and for the protection of textiles from attack by moths. [24] Thallium sulfate has been used as a depilatory and in the treatment of venereal disease, skin fungal infections, and tuberculosis. [25]
Tetrabutyltin is used as an antifouling paint for ships, for the prevention of slimes in industrial recirculating water systems, for combating freshwater snails that cause bilharzia, as a wood and textile preservative, and as a disinfectant. Tricyclohexyltin hydroxide is used as an acaricide. Triphenyltin hydroxide and triphenyltin acetate are used as fungicides. [26]
Zinc oxide is used as a weak antiseptic and in paints as a white pigment and mold-growth inhibitor. [27] Zinc chloride is a common ingredient in mouthwashes and deodorants, and zinc pyrithione is an ingredient in antidandruff shampoos. Galvanized (zinc-coated) fittings on roofs impede the growth of algae. Copper- and zinc-treated shingles are available. [15] Zinc iodide and zinc sulfate are used as topical antiseptics. [28]
Besides the individual toxic effects of each metal, a wide range of metals are nephrotoxic in humans and/or in animals. [29] Some metals and their compounds are carcinogenic to humans.[ citation needed ] A few metals, such as lead and mercury, can cross the placental barrier and adversely affect fetal development. [30] Several (cadmium, zinc, copper, and mercury) can induce special protein complexes called metallothioneins. [31]
An oxide is a chemical compound containing at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– ion with oxygen in the oxidation state of −2. Most of the Earth's crust consists of oxides. Even materials considered pure elements often develop an oxide coating. For example, aluminium foil develops a thin skin of Al2O3 that protects the foil from further oxidation.
The cumene process is an industrial process for synthesizing phenol and acetone from benzene and propylene. The term stems from cumene, the intermediate material during the process. It was invented by R. Ūdris and P. Sergeyev in 1942 (USSR), and independently by Heinrich Hock in 1944.
Clostridium is a genus of anaerobic, Gram-positive bacteria. Species of Clostridium inhabit soils and the intestinal tracts of animals, including humans. This genus includes several significant human pathogens, including the causative agents of botulism and tetanus. It also formerly included an important cause of diarrhea, Clostridioides difficile, which was reclassified into the Clostridioides genus in 2016.
Acenaphthene is a polycyclic aromatic hydrocarbon (PAH) consisting of naphthalene with an ethylene bridge connecting positions 1 and 8. It is a colourless solid. Coal tar consists of about 0.3% of this compound.
In industrial chemistry, a stabilizer or stabiliser is a chemical that is used to prevent degradation. Above all, heat and light stabilizers are added to plastic and rubber materials because they ensure safe processing and protect products against aging and weathering. In particular polyvinyl chloride would not be possible without stabilizers.
Benzyl benzoate is an organic compound which is used as a medication and insect repellent. As a medication it is used to treat scabies and lice. For scabies either permethrin or malathion is typically preferred. It is applied to the skin as a lotion. Typically two to three applications are needed. It is also present in Balsam of Peru, Tolu balsam, and in a number of flowers.
2-Phenylphenol, or o-phenylphenol, is an organic compound. In terms of structure, it is one of the monohydroxylated isomers of biphenyl. It is a white solid. It is a biocide used as a preservative with E number E231 and under the trade names Dowicide, Torsite, Fungal, Preventol, Nipacide and many others.
Thallium(I) carbonate is the inorganic compound with the formula Tl2CO3. It is a white, water-soluble salt. It has no or very few commercial applications. It is produced by treatment of thallous hydroxide with CO2.
Phenoxyethanol is the organic compound with the formula C6H5OC2H4OH. It is a colorless oily liquid. It can be classified as a glycol ether and a phenol ether. It is a common preservative in vaccine formulations. It has a faint rose-like aroma.
In organic chemistry, a dithiocarbamate is a functional group with the general formula R2N−C(=S)−S−R and structure >N−C(=S)−S−. It is the analog of a carbamate in which both oxygen atoms are replaced by sulfur atoms.
Carbazole is an aromatic heterocyclic organic compound. It has a tricyclic structure, consisting of two six-membered benzene rings fused on either side of a five-membered nitrogen-containing ring. The compound's structure is based on the indole structure, but in which a second benzene ring is fused onto the five-membered ring at the 2–3 position of indole.
Durene, or 1,2,4,5-tetramethylbenzene, is an organic compound with the formula C6H2(CH3)4. It is a colourless solid with a sweet odor. The compound is classified as an alkylbenzene. It is one of three isomers of tetramethylbenzene, the other two being prehnitene (1,2,3,4-tetramethylbenzene) and isodurene (1,2,3,5-tetramethylbenzene). Durene has an unusually high melting point (79.2 °C), reflecting its high molecular symmetry.
Metal toxicity or metal poisoning is the toxic effect of certain metals in certain forms and doses on life. Some metals are toxic when they form poisonous soluble compounds. Certain metals have no biological role, i.e. are not essential minerals, or are toxic when in a certain form. In the case of lead, any measurable amount may have negative health effects. There is a popular misconception that only heavy metals can be toxic, but lighter metals such as beryllium and lithium can be toxic too. Not all heavy metals are particularly toxic, and some are essential, such as iron. The definition may also include trace elements when abnormally high doses may be toxic. An option for treatment of metal poisoning may be chelation therapy, a technique involving the administration of chelation agents to remove metals from the body.
In chemistry, carbonylation refers to reactions that introduce carbon monoxide (CO) into organic and inorganic substrates. Carbon monoxide is abundantly available and conveniently reactive, so it is widely used as a reactant in industrial chemistry. The term carbonylation also refers to oxidation of protein side chains.
Ammonium thiosulfate is an inorganic compound with the formula [NH4]2S2O3. It is white crystalline solid with ammonia odor, readily soluble in water, slightly soluble in acetone and insoluble in ethanol and diethyl ether.
4-Nitrotoluene or para-nitrotoluene is an organic compound with the formula CH3C6H4NO2. It is a pale yellow solid. It is one of three isomers of nitrotoluene.
Zinc dimethyldithiocarbamate is a coordination complex of zinc with dimethyldithiocarbamate. It is a pale yellow solid that is used as a fungicide, the sulfur vulcanization of rubber, and other industrial applications.
Allyl iodide (3-iodopropene) is an organic halide used in synthesis of other organic compounds such as N-alkyl-2-pyrrolidones, sorbic acid esters, 5,5-disubstituted barbituric acids, and organometallic catalysts. Allyl iodide can be synthesized from allyl alcohol and methyl iodide on triphenyl phosphite, Finkelstein reaction on allyl halides, or by the action of elemental phosphorus and iodine on glycerol. Allyl iodide dissolved in hexane can be stored for up to three months in a dark freezer at −5 °C (23 °F) before decomposition into free iodine becomes apparent.
In chemistry, a fatty amine is loosely defined as any amine possessing a mostly linear hydrocarbon chain of eight or more carbon atoms. They are typically prepared from the more abundant fatty acids, with vegetable or seed-oils being the ultimate starting material. As such they are often mixtures of chain lengths, ranging up to about C22. They can be classified as oleochemicals. Commercially important members include coco amine, oleylamine, tallow amine, and soya amine. These compounds and their derivatives are used as fabric softeners, froth flotation agents, corrosion inhibitors, lubricants and friction modifiers. They are also the basis for a variety of cosmetic formulations.