Butylated hydroxytoluene

A HPLC with gradient elution method for the determination of the synthetic phenolic antioxidants (SPAs) propyl gallate (PG), tertiary butyl hydroquinone (TBHQ), butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) in food items is described. A C18 column served as the stationary phase; the gradient elution was formed by acetonitrile and water:acetic acid (1%). The UV detector was set at 280 nm. Under the recommended conditions, separation of the four SPAs was achieved in less than 8 min. Analytical characteristics of the HPLC method such as limit of detection, linear range, and reproducibility were evaluated. Extraction parameters were optimized for the recoveries of the SPAs in different types of food items (cooking oil, margarine and butter, and cheese). Before the HPLC separation, the SPAs were extracted with methanol/acetonitrile (1:1, v/v) and were subjected to vortex/ultrasonic treatment. The extracts were next kept in a freezer (∼2 h) to precipitate co-extracted components. Recoveries of the SPAs when spiked to cooking oil, margarine, butter and cheese at 50 and 200 mg l−1 were in the ranges 93.3–108.3% for PG, 85.3–108.3% for TBHQ, 96.7–101.2% for BHA and 73.9–94.6% for BHT. The method was applied to the determination of SPAs in 38 food items (16 cooking oils, ten margarine, six butter and six cheese samples). The levels of SPAs in positive samples are all below the legal limits of Malaysia.

Essential oils of three different Salvia species [Salvia aucheri var. aucheri (endemic), Salvia aramiensis and Salvia pilifera (endemic)] were screened for their possible antioxidant and antimicrobial properties as well as their chemical compositions. According to the gas chromatography (GC)/EIMS (gas chromatography/electron impact mass spectrum) analysis results; 41 (97.2%), 51 (98.5%) and 83 compounds (98.2%) were identified, respectively. While 1,8-cineole (30.5%), camphor (21.3%) and borneol (8.50%) are the major compounds for S. aucheri var. aucheri oil, beta-pinene (10.3%), was the main constituent for S. aramienesis together with 1,8-cineole (46.0%) and camphor (8.7%). In the case of S. pilifera oil, alpha-thujene (36.1%) and alpha-pinene (13.8%) determined as the major compounds. Antioxidant activity was employed by two complementary test systems namely 2,2'-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and beta-carotene/linoleic acid systems. Antioxidant activity of S. aramiensis was found to be higher than those of the others for the both systems (12.26+/-1.09 and 92.46%+/-1.64 microg mg(-1), respectively). Additionally, antioxidant activities of BHT, curcumin, ascorbic acid and alpha-tocopherol were determined in parallel experiments. In the case of antimicrobial activity, similar activity pattern was obtained (both in disc diffusion and MIC tests). Antimicrobial activity of S. aramiensis was followed by S. aucheri var. aucheri and S. pilifera, respectively. In these experiments, the most sensitive microorganism Acinetobacter lwoffii was followed by Candida albicans.

Aims:  To evaluate the antibacterial and free-radical scavenging (FRS) activities of propolis collected from three different areas of Sonoran Desert in northwestern Mexico [Pueblo de Alamos (PAP), Ures (UP) and Caborca (CP)].Methods and Results:  The antibacterial and FRS activities of Sonoran propolis were determined by the broth microdilution method and the DPPH (1,1-diphenyl-2-picrylhydracyl) assay, respectively. Propolis samples had antibacterial activity against only Gram-positive bacteria. The UP sample showed the highest antibacterial activity against Staphylococcus aureus [minimal inhibitory concentration (MIC) 100 μg ml−1] in a concentration-dependent manner (UP > CP > PAP). Caffeic acid phenethyl ester (CAPE), a UP propolis constituent, had very high growth-inhibitory activity towards Gram-positive bacteria, particularly against S. aureus (MIC 0·1 mmol l−1). To our knowledge, this is the first study showing a strong antibacterial activity of CAPE against S. aureus. Additionally, propolis CP exhibited high FRS activity (86% ± 0·3 at 100 μg ml−1) comparable with those of the reference antioxidants vitamin C (87·4% ± 1·7 at 70 μmol l−1) and BHT (66·07% ± 0·76 at 140 μmol l−1). The propolis compounds CAPE and rutin showed high FRS activity (90·4% ± 0·2 and 88·5% ± 0·8 at 70 μmol l−1, respectively).Conclusions:  Sonoran propolis UP and CAPE had strong antibacterial activity against S. aureus. In addition, propolis CP showed potent FRS activity comparable with those of vitamin C and BHT.Significance and Impact of the study:  The strong antibacterial and antioxidant properties of Sonoran propolis and some of its constituents support further studies on the clinical applications of this natural bee product against S. aureus and several oxidative damage-related diseases.

Under anaerobic conditions S-nitrosothiols 1a-e undergo thermal decomposition by homolytic cleavage of the S-N bond; the reaction leads to nitric oxide and sulfanyl radicals formed in a reversible manner. The rate constants, k(t), have been determined at different temperatures from kinetic measurements performed in refluxing alkane solvents. The tertiary nitrosothiols 1c (k1(69 degrees C) = 13 x 10(-3) min(-1)) and 1d (k1(69 degrees C) = 91 x 10(-3) min(-1)) decomposed faster than the primary nitrosothiols 1a (k1(69 degrees C) = 3.0 x 10(-3) min(-1)) and 1b (k1(69 degrees C) = 6.5 x 10(-3) min(-1)). The activation energies (E# = 20.5-22.8 Kcal mol(-1)) have been calculated from the Arrhenius equation. Under aerobic conditions the decay of S-nitrosothiols 1a-e takes place by an autocatalytic chain-decomposition process catalyzed by N2O3. The latter is formed by reaction of dioxygen with endogenous and/or exogenous nitric oxide. The autocatalytic decomposition is strongly inhibited by removing the endogenous nitric oxide or by the presence of antioxidants, such as p-cresol, beta-styrene, and BHT. The rate of the chain reaction is independent of the RSNO concentration and decreases with increasing bulkiness of the alkyl group; this shows that steric effects are crucial in the propagation step.

Abstract Coumarin and benzothiazole scaffolds can be found in a number of natural or synthetic antioxidants. In an effort to develop a novel radical scavenger and potential antioxidant, a series of coumarin derivatives containing 2-methylbenzothiazoline motif and related compounds was synthesized and evaluated for their DPPH (1, 1-diphenyl-2-picrylhydrazyl) and ABTS•+(2, 2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) radicals scavenging activities. Among them, 7-hydroxy-3-(2-methyl-2, 3-dihydrobenzo [d] thiazol-2- ...

Introduction: Cryopreservation of semen is routinely used in a variety of circumstances
including before assisted reproduction treatments, pre- radiation or chemotherapy treatment
and etc. The aim of this study was to compare the effect of Butylated hydroxytoluene (BHT)
and Glutathione supplemented cryopreservation medium on sperm parameters and amount of
DNA fragmentation during the freeze-thaw process.
Methods: Semen samples were obtained from 60 donors. After the determination of basic
parameters, groups of three sample with similar parameters were pooled and processed by Pure
Sperm gradient centrifugation. The semen samples were then diluted with normal freezing
medium (control) or a medium containing 5mM glutathione (test) and 0.5 mM BHT (test)
stored in liquid nitrogen. Frozen cryovials were thawed individually for 20 seconds in a water
bath (37 ˚C) for evaluation.
Results: Significant differences were observed in motility, viability and DNA fragmentation.
Motility and viability were significantly higher in treated groups with 0.5 Mm in 5 min BHT
than the control group and Glutathione 5mM (P<0.001).
Conclusion: Significant differences were observed in motility, viability and DNA
fragmentation. Motility and viability were significantly higher in treated groups with 0.5 Mm
in 5 min BHT than the control group and Glutathione 5mM (P<0.001).

Dipterocarpus alatus (Dipterocarpaceae) is a medicinal plant whose use is well known for the treatment of genito-urinary diseases. However, there is no report of its cytotoxic potential. In this study, the chemical composition, antioxidant and cytotoxic activities of extracts of the leaves, bark, twigs and oleo-resin from D. alatus are investigated. Cytotoxicity was measured by the neutral red (NR) assay against HCT116, SKLU1, SK-MEL2, SiHa and U937 cancer cell lines and antioxidant capacity was evaluated by DPPH, ABTS radical scavenging, and ferric reducing antioxidant power (FRAP) assays. The chemical composition was analyzed by gas chromatography–mass spectrometry (GC-MS). Leaf, bark and twig extracts exhibited stronger antioxidant activity than oleo-resin, with bark extract showing the highest antioxidant activity and the highest total phenolic content. All samples showed more cytotoxic activity against the U937 cell line than HCT116, SKLU1, SK-MEL2 and SiHa cells with oleo-resi...

Butylated hydroxytoluene (BHT), in concentrations of 500, 100, and 10 mg/liter (but not 1 mg/liter), significantly depressed methacholine-induced contractions of isolated rat and rabbit ileal preparations. BHT, in concentrations of 500, 100, 10, and 1 mg/liter, significatly (p &lt; ...

Vitamin A and vitamin A palmitate photostability were tested in different media. Ethanol and octyl octanoate solutions of these two vitamins, as such and with the addition of sunscreens (3,4 methylbenzilidencanfora, butyl methoxy dibenzoylmethane and octyl methoxycinnamate) or beta-carotene and butylated hydroxy toluene, were analysed spectrophotometrically after UVB or UVA irradiation. An O/W fluid emulsion with 0.5% w/w of retinyl palmitate, with and without butylated hydroxy toluene, was prepared. The oil containing the vitamin was extracted with HCl and aluminium sulfate and analysed spectrophotometrically after UVB or UVA irradiation. The fluid emulsion containing retinyl palmitate with and without butylated hydroxy toluene was stored at different temperatures and analysed every week spectrophotometrically for a month. Of the sunscreens tested butyl methoxy dibenzoylmethane showed the strongest protective action towards vitamin A and vitamin A palmitate, whereas beta-carotene d...