Tertiary-butyl-hydroquinone

A paired-ion, reversed-phase high-performance liquid chromatographic method was developed for the simultaneous determination of sweeteners (dulcin, saccharin-Na, and acesulfame-K), preservatives (sodium dehydroacetate, SA, salicyclic acid, BA, succinic acid, methyl-para-hydroxybenzoic acid, ethyl-para-hydroxybenzoic acid, n-propyl-para-hydroxybenzoic acid, n-butyl-para-hydroxybenzoic acid, and isobutyl-para-hydroxybenzoic acid), and antioxidants (3-tertiary-butyl-4-hydroxyanisole and tertiary-butyl-hydroquinone). A mobile phase of acetonitrile-50 ml aqueous tr-hydroxyisobutyric acid solution (pH 4.5) (2.2 3.4 or 2.4 3.6, v/v) containing 2.5 mM hexadecyltrimethylammonium bromide and a Clg column with a flow rate of 1.0 ml/min and detection at 233 nm were used. This method was found to be very reproducible detection limits ranged from 0.15 to 3.00 p,g. The retention factor (k) of each additive could be affected by the concentrations of hexadecyltrimethylammonium bromide and a-hydroxyisobu-tyric acid and the pH and ratio of mobile phase. The presence of additives in dried roast beef and sugared fruit was determined. The method is suitable for routine analysis of additives in food samples (81). 

Primary antioxidants terminate free radical chains and function as electron donors. They include the phenolic antioxidants, butylated hydroxyanisole (BHA), butylated hydroxy-toluene (BHT), tertiary butyl hydroquinone (TBHQ), alkylgalates, usually propylgallate (PG), and natural and synthetic tocopherols and tocotrienols. 

Synthetic antioxidants, such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), propyl gallate (PG), ascorbyl palmitate, and tertiary-butyl-hydroquinone (TBHQ), are used in soybean cooking oils and frying fats (230). These antioxidants are typically added at 0.01% for one antioxidant and 0.02% total for two or more. Natural antioxidants, derived from sage, rosemary, and green tea, are increasingly popular because of consumer preferences for natural food ingredients (231). 

Beilstein Handbook Reference) AI3-61039 Banox 20BA 1,4-Benzenediol (1,1-di-methylethyl)- 1,4-Benzenediol, 2-(1,1-dimethylethyl)- BRN 0637923 tert-Butyl-1,4-benzenediol 2-tert-Butyl-1,4-benzenediol Butylhydroquinone, tert- t-Butyl hydroquinone tert-Butylhydroquinone tertiary-Butylhydroquinone 2-t-Butylhydroquinone 2-tert-Butylhydroquinone 2-tert-Butyl(1,4)hydroquinone CCRIS 1447 2-(1,1-Dimethylethyl)-1,4-benzenediol Eastman MTBHQ EINECS 217-752-2 HSDB 838 Hydroquinone, t-butyl- Hydroquinone, tert-butyl- Mono-tert-butylhydroquinone Mono-tertiary butyl-hydroquinone MTBHQ NSC 4972 Sustane Sustane TBHQ TBHQ Tenox TBHQ. Preservative and antioxidant for foodstuffs and meat products color stable and useful as substitute for reactive antioxidants that tend to form purple complexes with iron or copper. White to light tan crystal solid soluble in organic solvents slightly soluble in water mp = 126.5-128,5 LD50 (rat orl) = 700 mg/kg, AC Ind, Inc Aceto Corp. Allchem Ind. Charkit Eastman Chem. Co. Lancaster Synthesis Co. Penta Mfg. Showa Denko UOP. 

This sequence of reactions is affected by prooxidants and by anti-oxidants. The former-frequently metals or radical-producing species-encourage initiation whilst anti-oxidants usually shorten the propagation sequence by promoting the termination reactions. Other compounds (synergists), added to anti-oxidants to enhance their activity, are mainly metal-chelating compounds such as citric acid, phosphoric acid, ascorbic acid or ethylenediamine tetra-acetic acid which inhibit the metal-catalysed initiation. Anti-oxidants include natural compounds like the tocopherols or synthetic materials such as butylated hydroxy-anisole (BHA), butylated hydroxytoluene (BHT), propyl gallate or tertiary butyl hydroquinone. 

Tenera palm, see Palmkernel oil Ternary phase diagrams, 237, 335 Terpenes, 38,143, 437 Tertiary butyl hydroquinone, 453... 

Meding B (1996) Occupational contact dermatitis from tertiary butyl hydroquinone (TBHQ) in a cutting fluid. Contact Dermatitis 34 224... 

Stabilisers. If stabilisation is necessary, e.g. to prolong the pot life or increase the storage stability, 0.01-0.03 % (solid) hydroquinone or tertiary butyl catechol can be added as a 1 to 5% solution in a suitable solvent. It should be borne in mind that the use of such substances has an effect on the drying time of the coating. 

Other additives of dermatological importance are hydroquinone, p-tertiary-butyl-catechol, cobalt naph-tenate, benzoyl peroxide, dimethylaniline, methyl-4-toluene sulphonate, p-tolyldiethanolamine, and dimethyl-, diethyl- and diphenylthiourea. These agents may cause both allergic and irritant contact dermatitis... 

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