Detection of azo dyes and aromatic amines in women undergarment Nguyen, Thao; Saleh, Mahmoud A.
Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering,
07/2016, Letnik:
51, Številka:
9
Journal Article
Recenzirano
Odprti dostop
Women are exposed to several chemical additives including azo dyes that exist in textile materials, which are a potential health hazard for consumers. Our objective was to analyze suspected ...carcinogenic azo dyes and their degradation aromatic amines in women underwear panties using a fast and simple method for quantification. Here, we evaluated 120 different samples of women underwear for their potential release of aromatic amines to the skin. Seventy-four samples yielded low level mixtures of aromatic amines; however eighteen samples were found to produce greater than 200 mg/kg (ppm) of aromatic amines. Azo dyes in these 18 samples were extracted from the fabrics and analyzed by reverse phase thin layer chromatography in tandem with atmospheric pressure chemical ionization mass spectrometry. Eleven azo dyes were identified based on their mass spectral data and the chemical structure of the aromatic amine produced from these samples. We demonstrate that planar chromatography and mass spectrometry can be really helpful in confirming the identity of the azo dyes, offering highly relevant molecular information of the responsible compounds in the fabrics. With the growing concern about the consumer goods, analysis of aromatic amines in garments has become a highly important issue.
High-performance thin-layer chromatography (HPTLC) coupled with negative ion desorption electrospray ionization high-resolution mass spectrometry (DESI-HRMS) was used for the analysis of ...anthraquinones in complex crude extracts of Chilean dermocyboid Cortinarii. For this proof-of-concept study, the known anthraquinones emodin, physcion, endocrocin, dermolutein, hypericin, and skyrin were identified by their elemental composition. HRMS also allowed the differentiation of the investigated anthraquinones from accompanying compounds with the same nominal mass in the crude extracts. An investigation of the characteristic fragmentation pattern of skyrin in comparison with a reference compound showed, exemplarily, the feasibility of the method for the determination of these coloring, bioactive and chemotaxonomically important marker compounds. Accordingly, we demonstrate that the coupling of HPTLC with DESI-HRMS represents an advanced and efficient technique for the detection of anthraquinones in complex matrices. This analytical approach may be applied in the field of anthraquinone-containing food and plants such as
spp. (rhubarb),
spp.,
spp.,
spp. and others. Furthermore, the described method can be suitable for the analysis of anthraquinone-based colorants and dyes, which are used in the food, cosmetic, and pharmaceutical industry.
Since the 1990s, food chemistry opened a new chapter in foods and plants investigation. An increasing attention to secondary metabolites and micro-constituents of nutraceutical interest present in ...foods has been noticed, supporting previous studies on macronutrient composition. Thanks to positive scientific opinions on the presence of bioactive molecules in plants and foods, the previous vision of exploring foods exclusively from a “caloric” point of view has been changed to looking at foodstuffs as having positive effects on human health.This book focuses on the optimization and validation of advanced analytical methodologies dedicated to the characterization and valorization of foods and plants containing bioactive molecules. Qualitative and quantitative characterization, food security, traceability, and innovation in the field of nutraceutical and functional nutrition will be of particular interest in order to stimulate a dialogue on correct nutrition concepts in a constantly changing cultural, technological, and climate context.
A new high-throughput method was developed to detect simultaneously riboflavin (Vitamin B
2), pyridoxine (Vitamin B
6), nicotinamide (Vitamin B
3), caffeine and taurine in energy drinks by multiple ...detection. Ten samples of energy drinks and six samples of beverages containing caffeine were prepared by degassing in an ultrasonic bath for 20
min. After chromatography, multi-wavelength scanning was performed by: (1) UV-absorbance measurement at 261
nm for nicotinamide and 275
nm for caffeine, (2) fluorescence measurement at 366/>400 and 313/>340
nm for riboflavin and pyridoxine, respectively, and (3) Vis-absorbance measurement at 525
nm for taurine, after post-chromatographic derivatization with ninhydrin reagent. Calibrations were linear or polynomial with determination coefficients
r
2
>
0.999. Overall recoveries of the five compounds were between 81 and 106% at three different concentration levels. Repeatabilities (RSD, %) of all substances in matrix were determined to be between 0.8 and 1.5%. Intermediate precisions (RSD, %) ranged between 3.6 and 7.4% for riboflavin, 2.8 and 6.3% for nicotinamide, 2.5 and 4.4% for caffeine, 2.1 and 2.9% for taurine and 0.5 and 4.0% for pyridoxine at different concentration levels. Mass confirmation was performed by a single quadrupole MS in positive electrospray ionisation (ESI) scan mode for all substances except taurine (negative mode). This method offers a good alternative for routine analysis due to its simplicity and at the same time reliability.
Background
Sphaeranthus indicus
L. is a well-known medicinal plant in folk medicine. A variety of biological activities and chemical substances in this plant have been reported. The phytochemical ...content and activity may vary according to geographic location. This study aims to determine the geographical significance, the analysis of the synergistic effect of phytochemicals, the identification of active compounds, and the determination of the action mechanism of
S
.
indicus
inflorescence methanolic extract against
Staphylococcus aureus
and
Klebsiella pneumonia
.
Results
The bands with Rf values of 0.92 and 1.0 showed antimicrobial activity, while all bands showed antioxidant activity. The first fraction showed the highest antimicrobial activity, and the pool of the second fraction showed the highest antioxidant activity. The kinetics of the antioxidants differed among the fractions. Analysis of synergistic effects showed that several compounds were involved in the activities. The bands with Rf 0.45, 0.55, 0.68, 0.79, and 0.85 were active components of the extract. Leakage of cell contents was detected at 260 and 280 nm wavelengths. Six different proteins and one nucleic acid band were detected after electrophoresis. The SEM analysis showed that the phytochemicals caused severe membrane damage.
Conclusion
The study revealed that the photochemical present in methanol extract of the inflorescence of
S. indicus
has a synergistic effect and acts on bacterial cell envelope. The five compounds were identified as active molecules belonging to the class of terpenoids. The result also signified the geographical area since thymol was identified for the first time in this plant at this location.
Graphical abstract
Anthraquinones (yellow dyes) were extracted from Japanese knotweed rhizomes with twelve extraction solvents (water; ethanol
(20%, 40%, 60%, 70% and 80%), ethanol, 70% methanol
, methanol, 70% acetone
..., acetone and dichloromethane). The obtained sample test solutions (STSs) were analyzed using high-performance thin-layer chromatography (HPTLC) coupled to densitometry and mass spectrometry (HPTLC-MS/MS) on HPTLC silica gel plates. Identical qualitative densitometric profiles (with anthraquinone aglycones and glycosylated anthraquinones) were obtained for STSs in all the solvents except for the STS in dichloromethane, which enabled the most selective extractions of anthraquinone aglycones emodin and physcion. The highest extraction efficiency, evaluated by comparison of the total peak areas in the densitograms of all STSs scanned at 442 nm, was achieved for 70% acetone
. In STS prepared with 70% acetone
, the separation of non-glycosylated and glycosylated anthraquinones was achieved with developing solvents toluene-acetone-formic acid (6:6:1, 3:6:1 and 3:3:1
/
) and dichloromethane-acetone-formic acid (1:1:0.1,
/
). Non-glycosylated anthraquinones were separated only with toluene-acetone-formic acid, among which the best resolution between emodin and physcion gave the ratio 6:6:1 (
/
). This solvent and dichloromethane-acetone-formic acid (1:1:0.1,
/
) enabled the best separation of glycosylated anthraquinones. Four HPTLC-MS/MS methods enabled the identification of emodin and tentative identification of its three glycosylated analogs (emodin-8-
-hexoside, emodin-
-acetyl-hexoside and emodin-
-malonyl-hexoside), while only the HPTLC-MS/MS method with toluene-acetone-formic acid (6:6:1,
/
) enabled the identification of physcion. Changes of the shapes and the absorption maxima (bathochromic shifts) in the absorption spectra after post-chromatographic derivatization provided additional proof for the detection of physcion and rejection of the presence of chrysophanol in STS.
Genista species are sources of antioxidant phenolic compounds such as O- and C-glycosylflavonoids and isoflavonoids. A combination of a DPPH scavenging assay with HPTLC-MS, a fast and efficient method ...for identification of bioactive compounds, has been applied for evaluation of the radical scavenging activity of metabolites from Genista saharae Coss. & Dur. Different organs collected at various periods have been compared. Identification of antioxidant compounds was obtained by elution of the major DPPH-inhibition zones. The resulting HPTLC-MS analysis under moderately polar conditions, coupled to the DPPH results led to the putative identification of two antioxidant isoflavone aglycones: 3',4',5,7-tetrahydroxyisoflavone (1) and ficuisoflavone (3), whereas polar migration conditions led to the identification of the glycosides 5-methoxy-4',7-trihydroxy-8-glucopyranosylisoflavone (4) and 4',5-dihydroxy-7-methoxyisoflavone-4'-O-β-D-gluco-pyranoside (5). Evaluation of percentage of inhibition of DPPH radical by the purified isoflavone 4 from the root extract showed that it affords a moderate contribution to the total radical scavenging activity of the extract.
HPTLC silica gel plates without and with fluorescence indicator F254 in combination with n-hexane-ethyl acetate-formic acid (20:19:1, v/v/v) as a developing solvent were explored for the ...HPTLC-densitometric and HPTLC-MS/(MSn) analyses of flavonoids. Pre-development of the plates with chloroform-methanol (1:1, v/v) was needed for reliable HPTLC-densitometric analyses of flavonoid aglycones in the whole RF range, while 2-step pre-development (1st methanol-formic acid (10:1, v/v), 2nd methanol), that decreased background signals of formic acid adducts, was required for HPTLC-MS analyses. Optimization with conditioning of the adsorbent layer with water before development and saturation of the twin trough chamber resulted in required decrease of the RF values of studied flavonoids (flavone, apigenin, luteolin, chrysin, quercetin dihydrate, myricetin, kaempferide, kaempferol, naringenin, pinocembrin).Detection was performed based on fluorescence quenching (on the plates with F254), natural fluorescence and after post-chromatographic derivatization with natural product reagent without or with further enhancement and stabilization of fluorescent zones with polyethylene glycol (PEG 400 or PEG 4000) or paraffin-n-hexane reagents. For all three reagents, drying temperature and time passed after drying influenced the intensity, which was increasing the first 20 min, and the stability (less than 2 h for PEGs and at least 24 h for paraffin-n-hexane) of the standards' zones.Optimal wavelengths for densitometric evaluation were selected based on in-situ absorption spectra scanned before and after derivatization and after stabilization. The developed method was tested via analyses of propolis, roasted coffee, rose hip, hibiscus, rosemary and sage crude extracts. To further increase the reliability of the obtained densitometric results HPTLC-MS/(MSn) analyses of all crude extracts were performed. Several phenolic and non-phenolic compounds were tentatively identified.Some possible interferences with phenolic acids (chlorogenic acid, rosmarinic acid, protocatechuic acid, gallic acid, syringic acid, ellagic acid, trans-cinnamic acid, o-coumaric acid, m-coumaric acid, p-coumaric acid, caffeic acid, ferulic acid, sinapic acid) that are often present in the extracts together with flavonoids were also examined.
High-performance thin-layer chromatography (HPTLC)-densitometry was directly combined with electrospray (ESI) tandem mass spectrometry for obtaining rapid and relevant structural identification of ...phospholipids (PL) species associated to membrane proteins (MP), in non-sulfur, purple bacteria having photosynthetic activity. Thus, species belonging to phosphatidylcholines (PC), phosphatidylethanolamines (PE), cardiolipins (CL) and phosphatidylglycerols (PG) associated to MP were investigated in bacterial membrane extracts from Rhodobacter (Rb.) blasticus, Rhodospirillum (R.) rubrum and Rhodobaca (Rbc.) bogoriensis, as well as those which are bound to a purified MP-photosynthetic complex from Rbc. bogoriensis.
PL-classes were separated using a 7-step gradient-solvent sequence with a previous acid plate preconditioning, using Automated Multiple Development. Band zones of the plate corresponding to PL classes were selected to ensure their direct transfer to ion-trap MS equipment through an elution-based interface.
Under the studied conditions, ESI
+
-MS spectra of PC and CL mostly showed sodium adducts (M + Na
+
) and M-2H + 3Na
+
, respectively, when recorded from the plate. The respective sodium adducts were fragmented in the ion-trap, and sodium remained as the charge of the fragment ions, thus being useful for their structural identification through MS/MS. ESI
-
-MS and MS/MS spectra of CL were also obtained as M-2H
2−
, as well as those of PE and PG species as M-H
-
and M
−
, respectively.
In this way, relative composition profiles of each studied PL-class by ESI-MS, and further identification of individual PL and the molecular species belonging to each of them by MS/MS were obtained.
Present paper describes the application of a recently developed method for the determination of six nucleobases (thymine, uracil, adenine, cytosine, guanine and guanosine), by high performance thin ...layer chromatography (HPTLC) in Ganoderma lucidum (GL) and Cordyceps sinensis (CS) - two mushrooms that have been widely revered in traditional Chinese medicines. The method used a simple mobile phase constituted of dicholoromethane-methanol-formic acid (8:2.25:0.8, v/v/v). Validation of the method according to USP guidelines proved the method to be accurate (97.1-99.9%) and precise (1.8-5.2% RSD). Results confirmed the abundance of nucleobases in various extracts of GL and CS wherein the aqueous extracts of GL and ethanolic extracts of CS were found to have the maximum nucleobase content. Identification of nucleobases in the samples was reconfirmed by hyphenated HPTLC-MS technique. HPTLC data were further processed by chemometric tools like heat maps, cluster dendrograms and principal component analysis for drawing relatability patterns among the samples. Since both GL and CS are well known for their therapeutic applications, nucleobase profiling in these medicinal mushrooms will provide an essential lead in establishing their use in the development of drug formulations.
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