Absence Of Hydroquinone Research Articles

Identifikasi hidroquinon dalam lotion pemutih dengan metode kromatografi lapis tipis

Background: Cosmetics have been widely used to enhance the appearance and make it look more attractive. One of the most commonly used cosmetics is lotion. As science and technology progress, many lotions are introduced to the market. As pharmaceutical regulations require, not all lotion products are safe, effective, and of high quality. However, many losses are caused by whitening lotion products in circulation, one of which is the addition of hydroquinone, a whitening substance that can cause damage to the skin.Objectives: This study aims to identify the hydroquinone content contained in whitening lotion.Methods: Experimental research using the Thin Layer Chromatography (KLT) method to test lotions for hazardous ingredients. It was conducted at the Chemistry Laboratory of Poltekkes Kemenkes Aceh in June 2022. Materials are whitening hand body lotion available online and not branded as many as five samples—determination of criteria, namely, low prices, high demand, and instant results. The single variable used in this study determines the presence or absence of hydroquinone in lotion samples.Results: This study has shown that five whitening lotion samples are positive. Sample S4 contains hydroquinone with an Rf value of 0,55 (< 0,05). Meanwhile, samples S1, S2, S3, and S5 were negative for hydroquinone.Conclusion: Some lotions tested have met the requirements of BPOM regulations and are safe to use, but one lotion is unsafe to use because it contains high hydroquinone.

Identifikasi Hidrokuinon Pada Krim Pemutih Wajah Yang Beredar Di Pasar Central Tompasobaru

The board of trustees of medicine and food throughout Indonesia was keeping a routine check on cosmetics that ran from October 2014 to September 2015, there are 30 types of cosmetics that contain the dangerous materials of 13 types of cosmetic product and 17 types of domestic production. The harmful substances identified in such cosmetics as K3 and K10 red dye (Rhodamin B), retinoic acid, mercury and hydroquinine. Hydroquinone is a supposition or a device that ACTS to treat hyperpigmentation in the outer part of the body as skin. Hyperpigmentation is the process by which skin is exposed to such areas as pimples, scars, or brown spots from frequent exposure to sunlight. Excessive use of hydroquinone can cause ookronosis, namely the skin has nodules like sand and bluish-brown in color, people with ookronosis will feel the skin like burning and itching. This type of research is descriptive, which aims to describe and describe the presence or absence of hydroquinone in facial whitening creams. The method used for laboratory testing is qualitatively using the thin layer chromatography method. Sampling using purposive sampling method, namely sampling where the sample taken is a cream that does not have a permit from the Food and Drug Supervisory Agency. From the results of research that has been carried out on three face whitening creams circulating in the Central Tompasobaru market and do not have a permit from the Food and Drug Supervisory Agency, one of which was declared positive for containing Hydroquinone, it is shown from the results of a qualitative test using the thin layer chromatography method which has the same value. with a standard solution of hydroquinone, which is Rf = 0.84 and under UV light 254 has a blackish fluorescence.

Identification and quantitative determination of arbutin in the herb of Orthilia secunda

Introduction. Orthilia secunda (L.) House is a perennial herb that grows in Europe, Siberia, Asia Minor and Central Asia. The herb of Orthilia secunda is actively used in folk medicine as a diuretic, wound-healing and anti-inflammatory agent. From literary sources it is known that this medicinal plant raw material (PRM) contains flavonoids, tannins, organic acids, vitamins, as well as simple phenols and their derivatives (arbutin and hydroquinone). The presence of arbutin is responsible for the plant's high antioxidant and anti-inflammatory properties. But the use of Orthilia secunda in official medicine is limited due to the lack of complete information on the chemical composition and criteria for standardization of this type of medicinal product.Aim. Identification and quantification of arbutin by chromatographic methods in Orthilia secunda (L.) House, harvested in various phytocenotic zones.Materials and methods. The investigated medicinal plant material – the herb of Orthilia secunda – was harvested in various phytocenotic zones: in July 2018, harvesting was carried out in the northern part of Kazakhstan (Kokshetau district), in July-August 2019 in the Perm Territory and in the Tyumen Region. Preliminary identification of arbutin and related phenols – gallic acid and hydroquinone – was carried out by high performance thin layer chromatography (HPTLC) on a CAMAG instrument with a UV cabinet (Merck HPTLC silica gel 60 F154 plates, 20 × 10), semi-automatic Linomat 5 applicator (sample application). Elution of the plates was performed in a CAMAG Automatic Developing Chamber (ADC2). Image fixation was performed on a CAMAG Scanner 3 spectrodensitometer. The quantitative determination of arbutin was carried out by the method of highperformance liquid chromatography, which was carried out on a Prominence LC-20 device (Shimadzu, Japan) according to the validated method described in the European Pharmacopoeia 10.0. Diode array detector SPD-M20A, column Intersil C18 column (250–4.6 mm, 5 μm) (Phenomenex, USA). The results were processed using the LabSolution software. The identification and quantification of arbutin was carried out in comparison with a standard solution containing a reference sample (RS) of arbutin (C = 0,025 mg/ml) and RS of hydroquinone (C = 0,0125 mg/ml).Results and discussion. HPTLC analysis made it possible to detect arbutin and gallic acid – the main product of hydrolytic degradation/ precursor of the biosynthesis of tannins of the hydrolysable group – in the herb of Orthilia secunda from different places of growth. HPLC analysis demonstrates a different chromatographic profile of Orthilia herb harvested in different phytocenotic zones. However, in all studied objects, the absence of hydroquinone and the presence of substances that can presumably be attributed to its derivatives were confirmed, which is confirmed by the visual similarity of the spectra of these compounds and the proximity of the extrema. It was found that arbutin does not belong to the marker (majority) compounds of Orthilia. Its content is low and reaches a maximum (about 0,021 %) in the herb of Orthilia secunda growing on the territory of Kazakhstan, while in the herb of Orthilia harvested in the Perm Territory arbutin was not identified. From the data obtained, it follows that the greatest accumulation of arbutin occurs in areas with a warmer and drier climate (northern part of Kazakhstan).Conclusion. HPTLC analysis of the herb Orthilia secunda allowed the identification of arbutin and gallic acid (the main precursor of tannins of the hydrolysable group). The results of HPLC analysis of Orthilia herb harvested in various phytocenotic zones suggest quantitative differences in the content of arbutin depending on the region of growth. From the experimental data, it follows that Orthilia growing in the northern part of Kazakhstan accumulates the maximum (0,021%) amount of arbutin, in comparison with the samples harvested in the Tyumen region and the Perm region. At the same time, Orthilia harvested in the Perm Territory does not accumulate arbutin. The presence of hydroquinone has not been confirmed (by HPTLC and HPLC methods); therefore, it is not justified to talk about the hydrolytic cleavage of arbutin in the process of biosynthesis or drying. However, in all studied objects there are peaks of substances with spectral characteristics like hydroquinone, which makes it possible to assume the presence of its derivatives. Therefore, it is not advisable to position arbutin as a marker compound of Orthilia secunda harvested on the territory of the Russian Federation, and to standardize raw materials for this compound.

Hydroquinone exposure accumulates neutral lipid by the activation of CDP-DAG pathway in Saccharomyces cerevisiae.

Benzene metabolites (HQ and BQ) are toxic compounds and their presence in human cause alteration in cellular respiration and kidney damage. In the current study, Saccharomyces cerevisiae has been used as a model organism and acute exposure of hydroquinone (HQ) decreased cell growth and increased reactive oxygen species (ROS). The expression of apoptosis regulatory genes (YCA1, NUC1, YSP1 and AIF1) were increased with HQ exposure in the wild-type cells. HQ exposure in the wild-type cells altered both the phospholipid and neutral lipid levels. Phosphatidylcholine is a vital membrane lipid that has a vital role in membrane biogenesis and was increased significantly with HQ. The neutral lipid results were supported with lipid droplets data and mRNA expression study. The phospholipid knockouts (Kennedy pathway) accumulated neutral lipids via the CDP-DAG (cytidine-diphosphate-diacylglycerol) pathway genes both in the presence and absence of HQ.

Comparative Study of 1,1‐Diphenyl‐2‐picryl‐hydrazyl Radical (DPPH•) Scavenging Capacity of the Antioxidant Xanthones Family

AbstractThis study compares the antioxidant capacities of the xanthone family and analyzes structure‐activity relationship. Thirty xanthones with various structural features were selected as the references and their antioxidant capacities were determined using the 1,1‐diphenyl‐2‐picryl‐hydrazyl radical (DPPH•) scavenging assay. The results of the assay indicated that these xanthones could scavenge the DPPH• in a dose‐dependent manner. It was found that their Trolox equivalent antioxidant capacity (TEAC) values varied by the presence or absence of hydroquinone (or catechol) group within the molecule. The former 15 xanthones (1‐15, TEAC=2.030‐0.568) with hydroquinone (or catechol) pattern possessed much higher TEAC values than the latter 15 xanthones (16‐30, TEAC=0.019‐0.002) without hydroquinone (or catechol) pattern. It was concluded that the presence of the hydroquinone (or catechol) group governs the antioxidant capacity of xanthone family. Other structural factors, such as isoprenylation, methylation, and glycosidation, play a minor role, unless they remove the hydroquinone (or catechol) pattern. These findings can be used to directly predict the antioxidant capacity of xanthone.

Influence of dihydroxybenzenes on paracetamol and ciprofloxacin degradation and iron(III) reduction in Fenton processes.

The degradation of paracetamol (PCT) and ciprofloxacin (CIP) was compared in relation to the generation of dihydroxylated products, Fe(III) reduction and reaction rate in the presence of dihydroxybenzene (DHB) compounds, or under irradiation with free iron (Fe3+) or citrate complex (Fecit) in Fenton or photo-Fenton process. The formation of hydroquinone (HQ) was observed only during PCT degradation in the dark, which increased drastically the rate of PCT degradation, since HQ formed was able to reduce Fe3+ and contributed to PCT degradation efficiency. When HQ was initially added, PCT and CIP degradation rate in the dark was much higher in comparison to the absence of HQ, due to the higher and faster formation of Fe2+ at the beginning of reaction. In the absence of HQ, no CIP degradation was observed; however, when HQ was added after 30min, the degradation rate increased drastically. Ten PCT hydroxylated intermediates were identified in the absence of HQ, which could contribute for Fe(III) reduction and consequently to the degradation in a similar way as HQ. During CIP degradation, only one product of hydroxyl radical attack on benzene ring and substitution of the fluorine atom was identified when HQ was added to the reaction medium.

Hydroquinone Identification in Whitening Creams Sold at Minimarkets in Minomartini, Yogyakarta

Whitening cream is a cosmetic which is contains chemicals and other materials that can etiolate black (brown) stain on the skin. Hydroquinone is a supplemental ingredient in whitening cream. Hydroquinone is the active ingredient that can control the production of uneven pigment, rather serves to reduce or inhibit the formation of melanin. The use of hydroquinone in cosmetics should not be more than 2%.The excessive use of hydroquinone can cause oochronosis,a rough, speckled bluish skin. The purpose of this study is to determine whether or not there are any hydroquinone in whitening cream sold at Minimarket in Minomartani, Yogyakarta. If found, further testing is done to determine the level of hydroquinone in it. This research describes the presence or absence of hydroquinone in the whitening creams and find out how much the percentage is. The method used is Thin Layer Chromatography (TLC) and serimetri titration. The qualitative study test results that 64% of the samples positively contain hydroquinone, whereas from the quantitative assay it is obtained that 89% of the samples are not suitably qualified according to Permenkes No.445/MENKES/PER/V/1998. There are 9 out of 14 whitening cream brands that contain hydroquinone and 8 of them contain levels of hydroquinone more than normal (> 2 %).Keywords: face whitening cream, hydroquinone, Thin Layer Chromatography, serimetri titration.

CD/AuNPs/MWCNTs based electrochemical sensor for quercetin dual-signal detection.

A dual-signal strategy was developed in the present work for quercetin (QR) electrochemical recognition and detection. Mercapto-β-cyclodextrin (HS-β-CD) self-assembled on gold nanoparticles and multi-walled carbon nanotubes modified electrode surface to fabricate an electrochemical sensor. Scanning electron microscope, electrochemical impedance spectroscopy, and cyclic voltammetry were employed to characterize the preparation process of the sensor. Hydroquinone (HQ) was chosen as an electrochemical marker for QR detection due to its small molecular size for the formation of inclusion with HS-β-CD. The results of UV-vis and differential pulse voltammetry demonstrate that the added QR can replace the included HQ in CD cavities, resulting in the dual-signal in electrochemical experiments composed of the decrease of oxidized current of HQ and the increase of oxidized current of QR. Compared with the sensor for QR detection in the absence of HQ, the sensor based dual-signal strategy exhibited a higher sensitivity with a wider detection range from 5.0 × 10(-9) to 7.0 × 10(-6)mol/L. With good selectivity, reproducibility, and stability, the sensor was applied for real samples detection with satisfactory results. The proposed dual-signal strategy can be readily extended to the selective recognition and sensitive detection of other molecules.

A mechanistic investigation of (Me 3Si) 3SiH oxidation

The interaction of (Me 3Si) 3SiH with O 2 is known to afford (Me 3SiO) 2Si(H)SiMe 3 in which the two oxygen atoms arise from the same oxygen molecule. In order to investigate the mechanism of this unusual reaction, the oxidation rates were measured in the temperature range 30–70 °C by following oxygen uptake in the presence and absence of hydroquinone as inhibitor. The rate constant for the spontaneous reaction of (Me 3Si) 3SiH with O 2 was determined at 70 °C to be ∼3.5 × 10 −5 M −1 s −1. A sequence of the propagation steps is proposed by combining the previous and present experimental findings with some theoretical results obtained at the semiempirical level. These calculations showed that the silylperoxyl radical (Me 3Si) 3SiOO undergoes three consecutive unimolecular steps to give (Me 3SiO) 2Si( )SiMe 3. Evidence has been obtained that the rate determining step is the rearrangement of silylperoxyl radical to a dioxirand-like pentacoordinated silyl radical. Our findings are of considerable importance for the understanding of the oxidation of hydrogen-terminated silicon surfaces.

Inhibition of Human T Lymphoblast Proliferation by Hydroquinone

Hydroquinone (HQ) is a major metabolite of benzene and is present in large quantities in cigarette tar as a result of the combustion of tobacco leaf pigments. We hypothesize that the immunosuppressive effects of cigarette smoking are due, in part, to the deposition of large quantities of HQ in the lungs. Exposure of primary human T lymphoblasts (HTL)in vitroto 50 μmHQ blocked IL-2-dependent proliferation by >90% with no loss in viability. Inhibition of DNA synthesis was observed immediately after the addition of HQ to the cells. However, this effect could be reversed up to 6 hr later by simply washing the cells and reculturing them in the absence of HQ. HQ did not significantly alter intracellular glutathione levels up to 24 hr later, and the presence of 50 μm2-mercaptoethanol or 500 μmdithiothreitol during the treatment did not prevent inhibition of DNA synthesis. HQ did not block binding of125I-IL-2 to the cells, but inhibited the IL-2-dependent progression of HTL through S phase of the cell cycle. These observations demonstrate that HQ, in concentrations comparable to those found in cigarette tar, is a potent inhibitor of IL-2-dependent T cell proliferation and may therefore help to explain the potent immunosuppressive effects of cigarette smoke on lung T lymphocytes.

Hydrogenolysis and hydrocracking of the carbonoxygen bond. 3. Thermolysis in tetralin of substituted anisoles

Mild pyrolysis and hydrogenolysis products of coal contain substantial amounts of pyrocatechol and resorcinol and their homologues whereas hydroquinone and its homologues are absent or present in only low amounts. In the present work the model compounds anisole and methyl-, methoxy- or hydroxy-substituted anisoles were studied to elucidate substituent effects on the carbon—oxygen bond cleavage in the presence of tetralin. The experiments were carried out at 618 K and 6 MPa (H 2). The major reaction is demethylation to the corresponding phenols. A steric effect can be seen in the ortho compounds and an electronic effect when the substituent is a strongly electron-releasing group. In compounds with oxygen substituents para to each other little or no hydroquinone can be isolated whereas the ortho and meta compounds, respectively, give pyrocatechol and resorcinol. It is suggested that the low yield or absence of hydroquinone in this work and in coal pyrolysis is due to the high reactivity of the intermediate p-hydroxyphenoxy radical, which gives rise to adducts and other compounds of high molar mass. The ortho radical is sterically hindered and the meta radical has a lower reactivity and are hence abstracting hydrogen from the hydrogen donor or coal.

The influence of some pyrazol-pyridine derivatives on prostaglandin synthetase activity in vitro

Four pyrazol-pyridine derivatives were found to increase about 3-fold the oxygen consumption by microsomes of ram seminal vesicles in the presence of arachidonic acid (100 μm) and 19 times prostaglandins generation. They had no influence on malondialdehyde formation. Radiochemical studies showed that mainly PGE 2 generation was increased. Stimulation of PG generation was observed also in bovine seminal vesicle microsomes but only in the absence of hydroquinone and glutathione. Tested compounds stimulate oxygen consumption in renal medulla but not in renal cortex, They had no influence on soybean lipoxidase activity.

Effect of hydroquinone on the electrochemical spectral sensitization at CdS single crystal electrode

AbstractThe spectral sensitization and supersensitization at n‐type CdS single crystal electrode have been investigated principally with the aim of obtaining some informations concerning the transformations of sensitizer (rhodamine B) and supersensitizer (hydroquinone) in the course of sensitization process. In the absence of hydroquinone, the dye is consumed approximately in proportion to the amount of electric charge passed through the electrode‐electrolyte interface. When hydroquinone is added into the dye‐containing electrolyte solution, the dye consumption is almost entirely suppressed and hydroquinone is quantitatively converted to p‐quinone.Taking into account the fastness of the reaction between hydroquinone and the supposed dye intermediate, and also the quenching of dye fluorescence by hydroquinone, it is suggested that the supersensitization is the result of an interaction between hydroquinone and the sensitizing dye in its excited state.

Beobachtungen zum mechanismus der Nenitzescu-reaktion

The structure of the carbmolamine 5 was recognised as an intermediate in the Nenitzescu-reaction but until recently it had been formulated as the quinone derivate 3. The course of the Nenitzescu-reaction in acetic acid would be understood if the last step by reduction with hydroquinone of 5 to the 5-hydroxyindol derivative 6 could be clarified. The 4,4′ and 4,6′-diindole derivates 11 and 12 as well as the acetoxyhydroxy-indolederivative 10 h in the absence of hydroquinone were established.

The Oxidation of Phenidone in Alkaline Solution

AbstractAlthough it is now recognized that in the presence of hydroquinone and sulphite, Phenidone does not oxidize further than the l electron stage to a free radical, oxidation in alkaline solution in the absence of hydroquinone. results in a series of highly coloured products. The separation of these products by chromatography and electrophoresis is described, derivatives of Phenidone being investigated as well as Phenidone itself.