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result(s) for
"Benzoates - analysis"
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Ultrasound-Assisted Extraction Coupled with Ion Chromatography for Benzoate Determination in Northern Thai Green Chili Dip: Box–Behnken Optimization, Greenness Assessment, and Application to Commercial Samples
by
Chanakul, Waraporn
,
Prasertboonyai, Kanyarak
,
Chuathong, Nissaya
in
benzoate
,
Benzoates - analysis
,
Capsicum - chemistry
2026
In this study, an ultrasound-assisted extraction (UAE) method combined with ion chromatography (IC) was developed, optimized and validated for the determination of benzoate in Northern Thai green chili dip. Four extraction variables were optimized using response surface methodology (RSM) based on a Box–Behnken design (BBD). The optimal conditions were a sample mass of 5.0 g, water volume of 20.0 mL, extraction temperature of 70 °C, and extraction time of 20 min. The validated method showed good linearity in the range of 0.5 to 100 mg L−1, limits of detection (LOD) and quantification (LOQ) of 0.305 and 1.070 mg L−1, respectively, precision in the range of 0.31 to 6.37% (%RSD, n = 11), and spiked recovery in the range of 85.50 to 107.80%, all of which were within the acceptable criteria. The AGREE score of the developed method was 0.45, which was higher than that of the conventional LLE-HPLC-UV method (0.27) due to the use of only deionized water as the extracting solvent and no generation of organic waste. The developed method was sensitive, validated, and environmentally friendly, and was successfully applied to the determination of benzoate in traditional condiment products. The proposed method may serve as an alternative approach for routine food analysis and quality control.
Journal Article
A label-free optical whole-cell Escherichia coli biosensor for the detection of pyrethroid insecticide exposure
by
Hammock, Bruce D.
,
Bever, Candace Spier
,
Polizzi, Karen M.
in
13/31
,
631/553/2691
,
631/553/552
2019
There is a growing need for low-cost, portable technologies for the detection of threats to the environment and human health. Here we propose a label-free, optical whole-cell
Escherichia coli
biosensor for the detection of 3-phenoxybenzoic acid (3-PBA), a biomarker for monitoring human exposure to synthetic pyrethroid insecticides. The biosensor functions like a competitive ELISA but uses whole-cells surface displaying an anti-3-PBA VHH as the detection element. When the engineered cells are mixed with 3-PBA-protein conjugate crosslinking that can be visually detected occurs. Free 3-PBA in samples competes with these crosslinks, leading to a detectable change in the output. The assay performance was improved by coloring the cells via expression of the purple-blue amilCP chromoprotein and the VHH expression level was reduced to obtain a limit of detection of 3 ng/mL. The optimized biosensor exhibited robust function in complex sample backgrounds such as synthetic urine and plasma. Furthermore, lyophilization enabled storage of biosensor cells for at least 90 days without loss of functionality. Our whole-cell biosensor is simple and low-cost and therefore has potential to be further developed as a screening tool for monitoring exposure to pyrethroids in low-resource environments.
Journal Article
Effects of acute arginine supplementation on neuroendocrine, metabolic, cardiovascular, and mood outcomes in younger men: A double-blind, placebo-controlled trial
by
Greenway, Frank L.
,
Lieberman, Harris R.
,
Rood, Jennifer C.
in
Amino acids
,
Arginine
,
Benzoate
2022
•Randomized, double-blind, placebo-controlled, crossover trial of healthy men•Comprehensive examination of acute arginine treatment, including metabolomics•Growth hormone was modestly increased, but limited endocrine effects were found•Vascular function and mood state were not altered by arginine•Gut microorganisms could affect arginine's effects on growth hormones
Arginine is an amino-acid supplement and precursor for nitric-oxide synthesis, which affects various biologic processes. The objective of this study was to determine the effects of arginine supplementation on growth hormone (GH) and metabolic parameters.
Thirty physically active, healthy men (age 18–39 y; body mass index: 18.5–25 kg/m2) were randomized in a double-blind, placebo-controlled, crossover trial. Arginine (10 g) and placebo (0 g) beverages were consumed after an overnight fast. Blood samples were collected at baseline and 1.5, 3.0, and 24 h after supplementation. The primary outcomes were serum GH and metabolomics. Also, amino acids, glucose, insulin, triacylglycerols, thyroid hormones, testosterone, cortisol, dehydroepiandrosterone, and mood state were assessed. Individuals with detectable increases in GH were analyzed separately (responders: n = 16; < 0.05 ng/mL at 1.5 h). Repeated-measure analyses of variance estimated the treatment effects at each timepoint.
Arginine levels increased at 1.5 h (146%) and 3.0 h (95%; P ≤ 0.001) and GH (193%) and thyroid-stimulating hormone (TSH; 10%) levels at 24 h (P < 0.05) after arginine versus placebo consumption. Arginine versus placebo increased glucose levels at 1.5 h (5%) and 3.0 h (3%; P ≤ 0.001). Arginine versus placebo did not affect other dependent measures, including mood state (P > 0.05), but changes in the urea, glutamate, and citric-acid pathways were observed. Among responders, arginine versus placebo increased GH at 1.5 h (37%), glucose at 1.5 h (4%) and 3.0 h (4%), and TSH at 24 h (9%; P < 0.05). Responders had higher levels of benzoate metabolites at baseline and 1.5 h, and an unknown compound (X-16124) at baseline, 1.5 h, and 24 h that corresponds to a class of gut microbes (P < 0.05).
Arginine supplementation modestly increased GH, glucose, and TSH levels in younger men. Responders had higher benzoate metabolites and an unknown analyte attributed to the gut microbiome. Future studies should examine whether the increased prevalence of these gut microorganisms corresponds with GH response after arginine supplementation.
Journal Article
Three spectrophotometric quantitative analysis of bisoprolol fumarate and telmisartan in fixed-dose combination utilizing ratio spectra manipulation methods
by
Abuseada, Hamed H. M.
,
Sattar, Osama I. Abdel
,
Abuelwafa, Mahmoud M.
in
639/638/11
,
639/638/224
,
Antihypertensive Agents - analysis
2024
Hypertension is a chronic condition with multiple drug regimens. Limiting these medicines is critical to patient compliance. Therefore, bisoprolol and telmisartan were recently developed in a fixed-dose combination to control blood pressure. The UV absorption spectra of bisoprolol and telmisartan overlapped significantly. Thus, three spectrophotometric methods have been developed for simultaneous determination of bisoprolol and telmisartan without prior separation. Method A is ratio difference of ratio spectra (RD), which measures the amplitude difference between (210–224) nm for bisoprolol and between (255–365) nm for telmisartan. Method B, the first derivative of ratio spectra (
1
DD), measures amplitude signals at 232 and 243 nm for bisoprolol and telmisartan, respectively. Method C is the mean centering of ratio spectra (MC), which measures the mean-centered ratio spectra's values at 223 nm for bisoprolol and 245 nm for telmisartan. The applied methods showed good linearity 2–20 µg/mL for bisoprolol, 4–32 µg/mL for telmisartan, with sufficient accuracy and precision. The methods were sensitive, with LOD values of 0.243 µg/mL and 0.596 µg/mL in RD method, 0.313 µg/mL and 0.914 µg/mL in
1
DD method, and 0.406 and 0.707 µg/mL in MC method for bisoprolol and telmisartan, respectively, the methods were validated per ICH criteria. The novel methods are precise and accurate and can be used for routine analysis and quality control of bisoprolol and telmisartan in pure and dosage form. Furthermore, the greenness of the approaches was evaluated using Analytical Greenness assessment (AGREE), and the suggested method received a high greenness score.
Journal Article
An eco-friendly HPLC method for simultaneous analysis of sildenafil and sodium benzoate in pulmonary arterial hypertension suspension dosage monitoring
2026
The purpose of this research is to develop a fast, environmentally friendly, precise, sensitive, and specific high-performance liquid chromatography (HPLC) method for the simultaneous determination of sildenafil and sodium benzoate in bulk raw materials and in the legally marketed reference drug (Revatio powder for oral suspension). The optimized mobile phase flow rate was 1 mL/min, with the mobile phase consisting of 600 mL of 0.2% v:v phosphoric acid aqueous solution and 400 mL of ethyl alcohol. The range of linearity used for sildenafil and sodium benzoate was 3.5–280 µg/mL (sildenafil) and 0.35–28 µg/mL (sodium benzoate), respectively. The wavelength used to analyze the samples was 230 nm; the sample size was 10 µL; and the analysis time was less than 4.5 min. The ultimate scores are as follows: 0.63 for the Analytical Greenness Metric for Sample Preparation (AGREEprep), 72.22 for the Analytical Green Star Area (AGSA), 80 for the Blue Applicability Grade Index (BAGI), 72 for the Click Analytical Chemistry Index (CACI), 88 for the Carbon Footprint Reduction Index (CaFRI), 89 for the Analytical Ecoscale (AES), and 78 for the Modified Green Analytical Procedure Index (MoGAPI), and an (A) letter score of 75.3% indicates the whiteness level using the Multi-color Assessment (MA) Tool, and all imply the high sustainability, greenness, whiteness, and economic wisdom of the current method. All validation characteristics have followed the International Council for Harmonisation (ICH) and United States Food and Drug Administration (US FDA) validation guidelines. Compared to complicated systems such as Ultra-performance Liquid Chromatography-tandem Mass Spectrophotometry (UPLC-MS), it has benefits including shorter retention times, less reagent usage, simultaneous analysis, and cheaper prices.
Journal Article
Development and validation of a novel HPLC-PDA method for the detection of preservatives in milk
by
de Abreu, Samanta Stinghen
,
de Lira, Fernanda Montanholi
,
Gonzaga, Natalia
in
Acetonitrile
,
Acids
,
Animals
2024
In this research paper we introduce and validate an enhanced method for the detection of sodium benzoate and potassium sorbate in milk. Sodium benzoate and potassium sorbate are widely employed as preservatives in the food industry; however, their use to restrict microbial growth in milk is prohibited. Our novel method achieved performance indicators in accordance with the criteria outlined by the International Conference on Harmonization. The extraction process involved sample dilution in acetonitrile (1:1 v/v), followed by subsequent centrifugation, filtration and injection into a high-performance liquid chromatography system with a photodiode array detector. The detection and quantification limits for sodium benzoate were determined to be 0.204 and 0.618 mg/l, respectively, while for potassium sorbate, these values were 0.108 and 0.328 mg/l, respectively. The accuracy ranged from 92.67 to 99.53%, with pH 4.0 selected as the optimal condition to ensure adequate resolution of the preservatives. The proposed method stands out due to its simplicity and speed, using a single reagent in modest quantities during sample preparation. This approach reduces toxicity and minimizes the production of pollutants during disposal. Furthermore, the novel method requires less raw material and energy consumption, aligning with the principles of green chemistry. Its lower quantitation limits render it more sensitive when compared to the official analysis. The preparation, separation, and simultaneous detection of these preservatives in a short period of time make this method suitable for integration into industrial workflows.
Journal Article
Chemical analysis of Brasilimeria Stach, 1949 (Hexapoda, Collembola, Neanuridae) hemolymphatic secretion, and description of a new species
by
Zeppelini, Douglas
,
Lopes, Norberto P.
,
Mendonça-Junior, Francisco J. B.
in
Acaricides
,
Alcohols
,
Aliphatic compounds
2019
Though Collembola is a widespread hexapod its use of chemical compounds for defense has been reported for only a few European species. Chemical composition analyses of the hemolymphatic secretion of Neotropical Collembola using Gas Chromatography with Mass Spectrometry (GC-MS) has been performed for the first time. The GC-MS analysis revealed 32 constituents, such as aliphatic and aromatic hydrocarbons, esters, alcohols, a phenol, an aldehyde and a ketone. Benzyl benzoate, the main component (at 46.98%), is a compound with known acaricide and insecticide properties. This is the first report on chemical constituents produced by Neotropical Pseudachorutinae, genus Brasilimeria, and will permit future secretion comparisons for Collembola. The taxonomic description of the species producing the secretion analyzed is provided; Brasilimeria assu sp. nov. (Collembola, Neanuridae, Pseudachorutinae) is the third known species of the genus; an updated diagnosis of the genus, an identification key, and further remarks on the species Brasilimeria Stach, 1949 are provided.
Journal Article
Acquisition of species-specific perfume blends: influence of habitat-dependent compound availability on odour choices of male orchid bees (Euglossa spp.)
by
Quezada-Euan, J. J. G.
,
Bång, J.
,
Eltz, T.
in
Analysis
,
anatomy & histology
,
Animal and plant ecology
2013
Male orchid bees (Euglossini, Apidae, Hymenoptera) expose species-specific blends of volatile chemicals (perfume bouquets) during their courtship display. The perfumes are acquired by collecting fragrant substances from environmental sources, which are then accumulated in specialised hind leg pouches. To balance the perfume composition, the males need to find and collect the required substances in specific relative amounts while facing seasonal, local or habitat-dependent differences in compound availability. Experience-dependent choice of odours, i.e. 'learned avoidance' of recently collected components, has been proposed as the mechanism that mediates the accumulation of the stereotypical compound ratios. In the present study, we used the presence of certain compounds in male hind leg pouches as proxy for the respective local compound availability, and investigated whether differences in content are correlated with differences in chemical choice assays. Our results suggest that volatile availability differs between localities (n = 16) as well as habitats (n = 2; coastal vs. inland) across the Yucatán peninsula, Mexico, for both studied species. Male Euglossa dilemma showed a pronounced preference for benzyl benzoate and eugenol at locations where those compounds were rare in hind leg extracts, as predicted by the learned avoidance model. No equivalent correlations were found for Euglossa viridissima. This is the first study to combine chemical analyses of perfumes with bioassays of odour choice. It strengthens the view that negative feedback from collected odours modifies future chemical choice and helps males to acquire specific perfume blends.
Journal Article
Pyrethroid Insecticides in Households from Urban Areas: An Association of the 3-PBA Metabolite and Hand Wipes
by
Panicharoen, Pongsaya
,
Robson, Mark Gregory
,
Siriwong, Wattasit
in
Benzoates - analysis
,
Benzoates - urine
,
Child, Preschool
2020
Pyrethroid exposure in the household environment affects children directly via inhalation or dermal exposure. Hand wipes can effectively predict pyrethroid exposure to young children along with the children's activities. The main purpose of this study is to identify the relationship between 3-PBA metabolites, hand wipe sample concentrations and multiple exposure factors, within the population of households with young children in urban Bangkok, Thailand.
Interviews were conducted with the parents of 80 children (aged 2-3 years). Urine was collected to analyze for 3-PBA metabolites and hand wipe samples were collected to analyze for cypermethrin. Both were analyzed by gas chromatography (GC/MS).
A Spearmen's correlation test of the increase of 3-PBA metabolites was significantly associated with an increase in hand wipe samples (cypermethrin) in children (r
= 0.226-0.274,
-value < 0.05). The binary logistic regression test presented an association between exposure factors with 3-PBA metabolite concentration. Gender presented a significant association with 3-PBA metabolites (
-value = 0.035, OR = 0.326, 95% CI 0.115-0.926), and frequency of bare feet inside the household presented a significant association with 3-PBA metabolites (
-value < 0.01, OR = 7.072, 95% CI 1.707-29.291). In addition, exposure factors were not significantly associated with wipe sample concentration (cypermethrin) but showed high risk of exposure to young children.
Suggestions to reduce the risk from long-term pyrethroid insecticide exposure to children living in households include increased education, awareness, and management.
Journal Article
Human Indoor Exposure to Airborne Halogenated Flame Retardants: Influence of Airborne Particle Size
by
Uding, Nancy
,
Hale, Robert
,
Schreder, Erika
in
Air Pollution, Indoor - analysis
,
Atoms & subatomic particles
,
Benzoates - analysis
2017
Inhalation of halogenated flame-retardants (HFRs) released from consumer products is an important route of exposure. However, not all airborne HFRs are respirable, and thus interact with vascular membranes within the gas exchange (alveolar) region of the lung. HFRs associated with large (>4 µm), inhalable airborne particulates are trapped on the mucosal lining of the respiratory tract and then are expelled or swallowed. The latter may contribute to internal exposure via desorption from particles in the digestive tract. Exposures may also be underestimated if personal activities that re-suspend particles into the breathing zone are not taken into account. Here, samples were collected using personal air samplers, clipped to the participants’ shirt collars (n = 18). We observed that the larger, inhalable air particulates carried the bulk (>92%) of HFRs. HFRs detected included those removed from commerce (i.e., polybrominated diphenyl ethers (Penta-BDEs: BDE-47, -85, -100, -99, and -153)), their replacements; e.g., 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB or EH-TBB); bis(2-ethylhexyl) 3,4,5,6-tetrabromophthalate (TBPH or BEH-TEBP) and long-produced chlorinated organophosphate-FRs (ClOPFRs): tris(2-chloroethyl)phosphate (TCEP), tris(1-chloro-2-propyl)phosphate (TCPP or TCIPP), and tris(1,3-dichloro-2-propyl)phosphate (TDCPP or TDCIPP). Our findings suggest estimates relying on a single exposure route, i.e., alveolar gas exchange, may not accurately estimate HFR internal dosage, as they ignore contributions from larger inhalable particulates that enter the digestive tract. Consideration of the fate and bioavailability of these larger particulates resulted in higher dosage estimates for HFRs with log Koa < 12 (i.e., Penta-BDEs and ClOPFRs) and lower estimates for those with log Koa > 12 (i.e., TBB and TBPH) compared to the alveolar route exposure alone. Of those HFRs examined, the most significant effect was the lower estimate by 41% for TBPH. The bulk of TBPH uptake from inhaled particles was estimated to be through the digestive tract, with lower bioavailability. We compared inhalation exposure estimates to chronic oral reference doses (RfDs) established by several regulatory agencies. The U.S. Environmental Protection Agency (EPA) RfD levels for several HFRs are considered outdated; however, BDE-99 levels exceeded those suggested by the Dutch National Institute for Public Health and the Environment (RIVM) by up to 26 times. These findings indicate that contributions and bioavailability of respirable and inhalable airborne particulates should both be considered in future risk assessments.
Journal Article