Butylated hydroxy-anisole

Di-/ l -butyl-4-methylphenol /2j5 i77-2/-i72,6-Di-/ l -butyl-4-methylphenol (di-/ l -butyl-/)-cresolDi-/ l -butyl-j )-cresol or butylated hydroxytoluene (BHT)) is most commonly used as an antioxidant in plastics and mbber. Use in food is decreasing because of legislation and it is being replaced by butylated hydroxy anisole (BHA) (see Antioxidants Eood additives). 

It should be mentioned that the Food Additives Analytical Manual (FAAM) [75] provides analysts with FDA evaluated methodology (partly subjected to collaborative study) needed to determine compliance with food additive regulations, including procedures for indirect food additives, such as butylated hydroxy-anisole (BHA), butylated hydroxytoluene (BHT), t-butylhydroxyquinone (TBHQ), dilaurylthiopropionate (DLTDP), fatty acid methyl esters (FAME), sodium benzoate, sorbitol, and others. 

Aromatic alcohols are called phenols. The simplest phenol, also called phenol, forms when a hydroxyl group replaces a hydrogen atom in the benzene ring. Phenol (carbolic acid) was used as an antiseptic in the 1800s. Today other phenol derivatives are used in antiseptic mouthwashes and in cleaning disinfectants such as Lysol. Phenols are easily oxidized, and this makes them ideal substances to use as antioxidants. By adding phenols such as BHT (butylated hydroxy toluene) and BHA (butylated hydroxy anisole) to food, the phenols oxidize rather than the food. 

Each 5 mL of VANTIN oral suspension contains cefpodoxime proxetil equivalent to 50 mg or 100 mg of cefpodoxime activity after constitution and the following inactive ingredients artificial flavorings, butylated hydroxy anisole, carboxymethylcellulose sodium, microcrystalline... 

Isotretinoin, a retinoid, is available as in 10-mg, 20-mg, and 40-mg soft gelatin capsules for oral administration. Each capsule also contains beeswax, butylated hydroxy-anisole, edetate disodium, hydrogenated soybean oil flakes, hydrogenated vegetable oil, and soybean oil. Gelatin capsules contain glycerin and parabens (methyl and propyl), with the following dye systems 10 mg, iron oxide... 

Hirose, M., Tanaka, H., Takahashi, S., Futakuchi, M., Fukushima, S. Ito, N. (1993b) Effects of sodium nitrite and catechol, 3-methoxy catechol, or butylated hydroxy anisole in combination in a rat mulhorgan carcinogenesis model. Cancer Res.. 53, 32-37... 

Many naturally occurring antioxidants are found in common foods. These include the green tea catechins,5 6 resveratrol from red wine,7 curcumin from curry powder,8 sul-foraphane from cruciferous vegetables,9 etc. Some synthetic materials are also added to foods to prevent rancidity of lipids. Examples include butylated hydroxy toluene (BHT) and butylated hydroxy anisole (BHA). 

The use of acidulants is an essential part of beverage formulation, with the acid component usually third in order of concentration. Acidulants performs a variety of functions in addition to their primary thirst-quenching properties, which are the result of stimulation of the flow of saliva in the mouth. Because it reduces pH, an acidulant can act as a mild preservative and in some respects as a flavour enhancer, depending on the other components present. In addition, by functioning as a synergist to antioxidants such as butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT) and ascorbic acid, acidulants can indirectly prevent discolouration and ranciditye. 

Oil-based, water-dispersible flavours (emulsions) are protected by the addition of oil-soluble antioxidants such as butylated hydroxy anisole (BHA) and butylated hydroxy toluene (BHT) to the oil phase before the emulsification process 1,000 mg/1 is the typical usage level in essential oils. Since the flavour emulsion will be used at the rate of about 0.1%, the level of antioxidant in the finished beverage will be of the order of 1 mg/1, which will safely comply with an ADI of 5 mg/kg body weight for either additive. 

Antioxidants include ascorbic acid, lecithin, and tocopherol and are added to all food products. Other antioxidants, such as butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT), and gallates, are permitted for use only in specific concentrations of food products. BHA is permitted for use in many countries, but BHT is not permitted because of possible toxicity, such as tumorigenicity. 

The level of polyunsaturates in the hydrophobe of a cationic surfactant influences its liquidity and also its resistance to oxidative degradation and color formation [24, 37]. The higher the polyunsaturate level and consequently the iodine value, the higher the liquidity and the higher the aqueous concentration of a softener dispersion that can be achieved. Products with high or even modest degrees of unsaturation frequently require the addition of an antioxidant such as the hindered phenol derivatives, butylated hydroxy toluene and butylated hydroxy anisole [24, 25, 38]. 

Figure 2. Shows the antioxidant activity of different rosemary extracts in comparison with Butylated Hydroxy Anisole (BHA). Although only 150 ppm of rosemary extract was used to stabilize lard, the antioxidant activity was higher compared to BHA.

Colour Test. Dissolve 0.1 g in 10 ml of ethanol, add 2 ml of a 2% solution of borax and a few crystals of 2,6-dichloroquinonechlo-roimide—faint blue (compare blue colour produced by butylated hydroxy anisole). 

Draw all resonance structures of the radical resulting from abstraction of a hydrogen atom from the antioxidant BHA (butylated hydroxy anisole)... 

Salad and cooking oils have varying amounts of natural antioxidants, mostly toco-pherols. With the introduction of synthetic antioxidants, it has been customary to supplement the natural antioxidants with the synthetic ones. Most commonly used synthetic antioxidants are butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT), propyl gallate (PG), ascorbyl palmitate, and tertiary butyl hydro-quinone (TBHQ). As a result of the questionable health implications of BHA and BHT, use of BHA and BHT is becoming rare. In recent times, TBHQ, because of its superior performance, has been used more extensively than the other synthetic antioxidants. Application and status of antioxidants have been reviewed (75). 

More recently Braun et al. 106) investigated the diffusion of stabilizers in molten polyethylene. Their results for butylated hydroxy toluene (BHT), butylated hydroxy anisole (BHA) and several hydrocarbons are given in Fig. 14. The Arrhenius... 

Buffers can also be provided in parenteral formulations to ensure the required pH needed for solubility and/or stability considerations. Other excipients included in parenteral products are preservatives (e.g., benzyl alcohol, p-hydroxybenzoate esters, and phenol), antioxidants (e.g., ascorbic acid, sodium bisulfite, sodium metabisulfite, cysteine, and butyl hydroxy anisole), surfactants (e.g., polyoxyethylene sorbitan monooleate), and emulsifying agents (e.g., polysorbates). An inert gas (such as nitrogen) can also be used to enhance drug stability. Stability and solubility can also be enhanced by the addition of complexation and chelating agents such as the ethylenediaminetetraacetic acid salts. For a more detailed list of approved excipients in parenteral products, the reader should consult the monographs within the USP. 

Some antioxidants possess antimicrobial properties, such as propyl gallate and butylated hydroxy anisole, which are somewhat effective against bacteria. Butylated hydroxy toluene has demonstrated some antiviral activity. Compatibility of antioxidants with the drug, packaging system and the body should be studied carefully. For example, tocopherols may be absorbed onto plastics ascorbic acid is incompatible with alkalis, heavy metals, and oxidizing materials such as phenylephrine, and sodium nitrite and propyl gallate forms complexes with metal ions such as sodium, potassium and iron. 

Lamikanra A, Ogunbayo TA. A study of the antibacterial activity of butyl hydroxy anisole (BHA). Cosmet Toilet 1985 100(10) 69-74. 

In addition to its use in resins and adhesives, phenol is also the starting material for the synthesis of chlorinated phenols and the food presen-atives BHT (butylated hydroxytoluene) and BHA (butylated hydroxy-anisole). Pentachlorophenol, a widely used wood preservative, is prepared by reaction of phenol with excess CI2. The herbicide 2,4-D (2,4-dich)< -phenoxyacetic acid) is prepared from 2,4-dichlorophenol, and the hospital antiseptic agent hexachlorophene is prepared from 2,4,5-trichlorophenol. 

A mixture of polysorbate 20 and PEG 400 in combination with povidone and butylated hydroxy anisole (BHA) solubilizes 75 mg bexarotene, a benzoic acid derivative that is a selective activator of the retinoid X receptor indicated for the treatment of T-cell lymphoma, in Targretin soft gelatin capsules. The dose of bexarotene is 300-750 mg (four to ten capsules) once daily and Targretin soft gelatin capsules should be stored at controlled room temperature. Targretin has been available in the United Kingdom (UK) since 2001, and is also available in the United States of America (USA). 

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