Tartrazine Concentration Research Articles

Electrochemical reduction of tartrazine at multi-walled carbon nanotube-modified pyrolytic graphite electrode

Electrochemical reduction of tartrazine on multi-walled carbon nanotube-modied pyrolytic graphite electrode is investigated. A simple, sensitive and inexpensive method for determination of tartrazine in drinks is proposed. The accuracy and reproducibility of the determination method for various known amounts of tartrazine were evaluated. This method was satisfactorily applied for the determination of tartrazine in drinks. The reduction peak currents were proportional to tartrazine concentrations over two intervals in the range from 2.0 to 70.0 mg l−1 and from 70.0 to 230.0 mg l−1, and the detection limit for tartrazine is 0.5 mg l−1.

Preparation, Characterization, and Environmental Application of Crosslinked Chitosan-Coated Bentonite for Tartrazine Adsorption from Aqueous Solutions

The preparation, characterization, and environmental application of crosslinked chitosan-coated bentonite (CCB) beads for tartrazine adsorption have been investigated. CCB beads were characterized by using Fourier transform infrared spectrophotometer (FTIR), scanning electron microscope (SEM), and Brunauer–Emmett–Teller (BET) surface area and Barrett–Joyner–Halenda (BJH) pore size distribution analyses were also determined. The values of pH of the aqueous slurry and pH of zero point charge (pHZPC) were almost equal. The adsorption at equilibrium of tartrazine was found to be a function of pH of the solution, stirring rate, contact time, and tartrazine concentration. The optimum conditions for tartrazine adsorption were pH 2.5, stirring rate of 400 rpm and contact time of 80 min. Pseudo-first-order and pseudo-second-order models were used to analyze the kinetics of adsorption with the latter found to agree well with the kinetics data, suggesting that the rate determining step may be chemisorption. The two most common isotherm models, Langmuir and Freundlich, were used to describe the adsorption equilibrium data. On the basis of Langmuir isotherm model, the maximum adsorption capacities were determined to be 250.0, 277.8, and 294.1 mg g−1 at 300, 310, and 320 K, respectively. Desorption studies were carried out at different concentrations of EDTA, H2SO4, and NaOH. All desorbing solutions showed poor recovery of tartrazine.

Physiological characterization ofEnterococcus faecalisduring azoreductase activity

Azo dyes are widely used in the food, pharmaceutical, paper, and textile industries. Some azo dyes are known to produce carcinogenic compounds upon reductive cleavage of the azo bond (N=N) by intestinal flora. There is not much information available on the effect of these dyes on the physiology of the gut microflora as well as their kinetics of reduction in different environments. The azoreductase activity of Enterococcus faecalis , an important opportunistic intestinal pathogen, was tested using the azo dyes Methyl Red, Direct Blue 15 and tartrazine under the following conditions: a complex supplemented brain heart infusion (BHIS) medium under aerobic and anaerobic conditions, a simple phosphate-buffered saline glucose (PBSG) medium under anaerobic conditions, and cell extracts using NADH and NADPH as electron donors, under aerobic conditions. The kinetics of reduction in all these conditions was determined. The effect of high and low concentrations of each dye on the growth of E. faecalis was also tested. Our results show that the sulfonated azo dye tartrazine was completely reduced extracellularly in BHIS under aerobic and anaerobic conditions while the other sulfonated azo dye, Direct Blue 15 was completely reduced only under anaerobic conditions. The non-polar azo dye, Methyl Red was also completely reduced, with the highest rate of reduction in both conditions. The generation time of E. faecalis in the presence of high concentration of tartrazine was significantly lower than the control, while the generation time was unaffected in the presence of low and high concentrations of Methyl Red, Direct Blue 15 and 20 uM tartrazine. Our results suggest that the metabolism of different azo dyes by E. faecalis depends on the physiochemical properties of the azo dyes and the conditions of the surrounding environment in the presence of actively dividing cells. Key words: azo dyes, Methyl Red, Direct Blue 15, tartrazine, Enterococcus faecalis, growth phase, azoreductase

Tartrazine modified activated carbon for the removal of Pb(II), Cd(II) and Cr(III)

A two in one attempt for the removal of tartrazine and metal ions on activated carbon has been developed. The method was based on the modification of activated carbon with tartrazine then its application for the removal of Pb(II), Cd(II) and Cr(III) ions at different pH values. Tartrazine adsorption data were modelled using both Langmuir and Freundlich classical adsorption isotherms. The adsorption capacities q m were 121.3, 67 and 56.7 mg g −1 at initial pH values of 1.0, 6.0 and 10, respectively. The adsorption of tartrazine onto activated carbon followed second-order kinetic model. The equilibrium time was found to be 240 min at pH 1.0 and 120 min at pH 10 for 500 mg L −1 tartrazine concentration. A maximum removal of 85% was obtained after 1 h of contact time. The presence of tartrazine as modifier enhances attractive electrostatic interactions between metal ions and carbon surface. The adsorption capacity for Pb(II), Cd(II) and Cr(III) ions has been improved with respect to non-modified carbon reaching a maximum of 140%. The adsorption capacity was found to be a pH dependent for both modified and non-modified carbon with a greater adsorption at higher pH values except for Cr(III). The enhancement percent of Pb(II), Cd(II) and Cr(III) at different pH values was varied from 28% to 140% with respect to non-modified carbon. The amount of metal ions adsorbed using static regime was 11–40% higher than that with dynamic mode. The difference between adsorption capacities could be attributed to the applied flow rate.

Evaluation of a novel standardized system for collection and quantification of oral fluid

Standardization in collection and testing of oral fluid is lacking. A novel standardized collection and quantification system for oral fluid testing was evaluated. Sample collection volumes were determined. For determination of the saliva content in oral fluid samples, tartrazine, which is an integral part of the saliva extraction solution serving as an internal standard, was used. Results were compared with those obtained by employing glucose as a 'supplemental internal standard' for determination. Analytical performance of the new system for collection and quantification of oral fluid was evaluated. Calcium and magnesium analyte concentrations in oral fluid samples were measured with a routine laboratory method and compared to a reference method. Volumes of oral fluid samples collected ranged from 4.9 to 10.5 mL. The mean saliva content in oral fluid samples was found to be 65.5 percent by volume (vol.-%) when determined through the tartrazine concentration and 65.0 vol.-% when determined through the glucose concentration. Evaluation of analytical performance revealed interassay imprecision coefficients of variation (CVs) ranging from 1.5% to 3.2% and intraassay imprecision CVs from 1.1% to 2.5%. When linearity was tested, a quasi-linear curve was observed (R2=0.99). Comparison of two different methods for determination of calcium and magnesium concentrations showed correlations of R2=0.96 for calcium and R2=0.97 for magnesium. The new system for collection and quantification of oral fluid helps to improve standardization of pre-analytics in oral fluid testing and to provide reliable and accurate quantification of analytes in oral fluid samples.

The effect of tartrazine on histamine release from rat peritoneal mast cells

The release of histamine from purified rat peritoneal mast cells induced by specific antigen (egg albumin), compound 48/80 and calcium ionophore A23187 was modified by tartrazine. Histamine release induced by 48/80 and antigen was inhibited by the presence of 10 −5 to 10 −2M tartrazine. The inhibitory effect on egg albumin induced histamine release was maximal when the tartrazine was added simultaneously with egg albumin, and was reduced by increased preincubation of the cells with tartrazine. Tartrazine had a small inhibitory effect on ionophore induced release at high concentrations, but augmented histamine release at tartrazine concentrations of 10 −3 and 10 −4M. Augmentation of ionophore induced release was maximal at between 0–5 min preincubation of the cells with tartrazine.

Tartrazine-induced chromosomal aberrations in mammalian cells

Tartrazine (FD & C Yellow No.5) has been shown to induce chromosomal aberrations in fibroblast cells of Muntiacus muntjac in vitro. M. muntjac cells were exposed to various concentrations of tartrazine (in the 5–20 μg/ml range) and were evaluated for induced chromosomal aberrations after two different periods of culture. Total percentages of chromosomal aberrations were significantly increased above control levels in all experimental groups. The results suggest that further studies are needed to determine the potential mutagenic effects of tartrazine.

Effects of tartrazine of different contractile stimuli in guinea pig tracheal muscle.

Tracheal smooth muscle obtained from ovalbumin-sensitized guinea pigs contracted with micromolar concentrations of tartrazine and indomethacin. The contractions were slightly reduced by clemastine, but were completely blocked by the SRS-A antagonist FPL 55712. Arylsulfatase B, which is an enzyme that inactivates SRS-A, also abolished the contractions induced by tartrazine. Contractions induced by carbacholine, histamine, egg albumin and arachidonic acid were slightly reduced by indomethacin and tartrazine. Tartrazine like indomethacin inhibited the generation of thromboxanes from human platelets. We suggest that SRS-A plays an important role in the immediate hypersensitivity reactions of tartrazine and indomethacin in guinea pig trachea.

976. One more advance in tartrazine metabolism: Jones, R., Ryan, A. J. & Wright, S. E. (1964). The metabolism and excretion of tartrazine in the rat, rabbit and man. Fd Cosmet. Toxicol.2, 447. Westöö, G. (1965). On the metabolism of tartrazine in the rat. Acta chem. scand.19, 1309

Food dyes, or color additives, are often added into foods, cosmetics and beverages during processing to improve the sensory attributes of the final products. However, the toxicity of tartrazine (TZ), one of the most common azo-dyes, is still unclear, and needs to be ascertained by further study. Hence, in the present study, we aimed to evaluate the effects of TZ consumption on health by using a teleost, crucian carp (Carassius auratus) as the experimental fish. TZ consumption (1.4, 5.5 and 10 mg/kg bwt/day) could cause severe histopathological and cellular alterations in intestine and liver. The height of intestinal villus, thickness of intestinal muscle, and microvilli density were also affected. With the increasing of TZ concentrations, the activities of antioxidant enzymes (CAT, SOD and GSH-Px), exhibited a decreasing trend, while the contents of MDA elevated. Upregulations of pro-inflammatory cytokines (il6 and tnfα), anti-inflammatory cytokines (il8, and il10) and other immune related genes (complement component 3 (c3), lysozymes (lyz), β-defensin 3 (defb3)), were observed after TZ uptake. In addition, TZ consumption also affected the community structure of the microbiota in the intestine of crucian carp. The amount of some probiotic bacteria (Roseomonas, Rhodococcus and Bacillus) and the bacteria (Bacteroides and Clostridium), producing short chain fatty acids, were significantly reduced, and some pathogenetic microorganisms (e.g. Bdellovibrio and Shewanella) were significantly increased after TZ uptake. In summary, the data in the present study indicate that TZ consumption, even at a low concentration, may lead to adverse effects on fish health. Therefore, in aquaculture, it is necessary to be informed about the hazardous effects of TZ, and more attentions should be focused on using natural substitutes.