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•An alternative CZE method was developed for the inspection of sulfite in seafood.•CZE method use simple instrumentation and separation occurs in less than 3 min.•Simultaneous ...extraction/derivatization step requires only 30 min.•The instability of the sulfite was suppressed by its derivatization with formaldehyde.•Full validation confirmed method fitness for application in seafood.
Sulfite is widely used to prevent enzymatic browning in shrimp and lobster processing. However, sulfite may cause allergy in sensitive consumers. Thus, regulatory agencies set limits for its use. Sulfite is usually controlled by the normalized Monier-Williams (MW) titrimetric method that allows a limited number of samples to be analyzed. This manuscript consolidates an innovative method for sulfite inspection in seafood by capillary zone electrophoresis with diode array detector (CZE-DAD). A simple, fast, and simultaneous extraction and derivatization method was developed to provide high throughput for analytical routine. The high instability of the sulfite was suppressed by its derivatization with formaldehyde producing hydroxymethylsulfonate. The evaluation of its analytical performance yielded excellent results in compliance with the strict parameters required for metrological accreditation. The CZE-DAD method was selective and specific when submitted to confirmatory evaluations by liquid chromatography coupled to mass spectrometry. The limit of detection (3.50 mg kg−1), limit of quantitation (11.7 mg kg−1) and recoveries (99–103%) were adequate for sample analysis. The measurement uncertainty was estimated by the propagation of errors and experimental standard uncertainties (precision, accuracy, and analytical curves) and type B uncertainties from traceable measurement instruments. The low relative uncertainty (10%) and the adequate reproducibility demonstrated method suitability. The CZE-DAD results were compared to the MW method through the respective expanded standard uncertainties and normalized error. This new method is promising to be used in seafood inspection and continuous laboratory evaluations using instrumentation not very expensive to acquire and maintain.
The non-thermal plasma (NTP) technique is an advanced oxidation technology (AOT) applied to the degradation of organic compounds in water. In this study, the degradation kinetics of indigo carmine ...was investigated systematically, applying N2-NTP, O2-NTP, ozonolysis and hydrogen peroxide and the results were compared. The transient species (OH, O and NO radicals) formed with the NTP discharge at the gas-liquid interface and their products (NO3−, NO2−, H2O2) stabilized by the water, were identified and quantified. These species contribute to the effects on the chemical characteristics of the water, such as a decrease in the pH and increase in the conductivity and redox potential. Additionally, the stabilization of the oxidative species was estimated from the degradation reactions induced by the post-discharge effect, which was significant in the case of N2-NTP, due to the presence of long-lived species, such as nitrite and nitrate. The kinetics study revealed first-order kinetics for IC color removal and the rate constant values followed the order: O2-NTP (3.0 × 10−1 min−1) > O3 (1.4 × 10−1 min−1) > N2-NTP (2.2 × 10−2 min−1) > H2O2 (negligible). Also the main by-products of N2-NTP, O2-NTP and ozonolysis degradation reaction were identified by ultra-fast liquid chromatography coupled with mass spectrometry. The route fragmentation showed the formation of indole intermediates, such as isatin, which is an important precursor in organic synthesis.
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•The species OH.• and NO• formed with the NTP discharge were identified•Degradation rate as follows: O2-NTP > O3 >, N2-NTP > H2O2.•Post-discharge effect was significant for N2-NTP.•IC degradation by-products identified were similar for O2-NTP, O3 and N2-NTP.
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Although rare, amoebic keratitis (AK) is a disease caused by Acanthamoeba spp. that can lead to blindness. The drugs currently available for its treatment are very toxic, which has ...motivated the investigation for more effective and safe therapeutic options. In this study, the in vitro activity of ß-caryophyllene (BCP) was exploited taking into account its action against other protozoans as well as its well-known healing and anti-inflammatory properties (aspects relevant for the AK pathogenesis). On the other hand, high volatilization and oxidation phenomena are found for this compound, which led to its incorporation into nanoemulsions (NEs). Two emulsifying agents were tested, resulting in monodisperse systems with reduced droplet size (<265 nm) and high surface charge (positive and negative for NEs prepared with cetrimonium bromide −CTAB and Phosal® 50+, respectively). NEs prepared with CTAB were shown to be more stable after long-term storage at 4 and 25 °C than those prepared with Phosal®. Pure BCP, at the highest concentration (500 µM), resulted in a level of inhibition of Acanthamoeba trophozoites equivalent to that of reference drug (chlorhexidine). This activity was even greater after oil nanoencapsulation. The reduced droplet size could improve the interaction of the oil with the microorganism, justifying this finding. Changes in surface charge did not impact the activity. Positively charged NEs improved the interaction and retention of BCP in the cornea and thus should be prioritized for further studies.
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•Gallic acid, ellagic acid, quercetin, and isoquercetrin were the major phenolics.•Intermediate-ripe and fully ripe stages showed higher content of phenolic compounds.•Fructose and ...glucose were higher in the fully ripe stage.•K, Na, Ca, and Mg were higher in the intermediate and intermediate-ripe stages.
Grumixama (Eugenia brasiliensis Lamarck) is a native fruit of the Atlantic rain forest that belongs to Myrtaceae family. It presents economic potential due to the attractive sensory attributes and bioactive compounds. This study determined physicochemical characteristics, minerals (K, Na, Ca, Mg, Mn), sugars (fructose, glucose, sucrose), total content of phenolics, proanthocyanidins, and anthocyanins, individual phenolic compounds, and antioxidant capacity at three ripening stages of grumixama from two growing locations (Florianópolis and São Ludgero, Santa Catarina state, Brazil). Of the 23 phenolic compounds quantified, gallic acid, ellagic acid, quercetin, and isoquercetrin were the major (with values up to 69.08 mg/100 g fresh weight). Fructose (up to 5.28 g/100 g fresh weight) was the main sugar, and K (up to 589.30 mg/100 g fresh weight) was the major mineral, followed by Ca, Na, and Mg (up to 149.02, 117.52, and 80.18 mg/100 g fresh weight, respectively). More mature fruits had the highest levels of total phenolics (up to 469.18 mg gallic acid equivalent/100 g fresh weight), anthocyanins (up to 518.64 mg cyanidin 3-glucoside equivalent/100 g fresh weight), and proanthocyanidins (up to 420.70 mg catechin equivalent/100 g fresh weight). The influence of growing location and ripening on nutritional and physicochemical characteristics was confirmed. There was a statistically significant interaction (p < 0.05) between both factors for almost all parameters evaluated. The results showed that grumixama fruits could contribute to the daily intake of nutritional and bioactive compounds for consumers' health.
► A MECK–UV method was developed using a full factorial for 5-HMF separation. ► Multiple regression enables the mathematical relationship for a response function. ► The analysis time is shorter than ...others CE methods reported in the literature. ► Under optimal CE conditions, 5-HMF peak was recorded in less than 0.7min. ► Samples were dissolved in purified H2O and injected without any other pretreatment.
In this study, 5-hydroxymethylfurfural (5-HMF) determination was carried out by a micellar electrokinetic capillary chromatography (MEKC) methodology, using caffeine as the internal standard (IS). The optimisation of the electrolyte composition was approached using a 32 full factorial design with a central point to study the MEKC electrolyte components. Inspection of the response surface indicated that the optimal electrolyte composition was 5mmolL−1 sodium tetraborate (STB, pH 9.3) containing 120mmolL−1 sodium dodecyl sulphate (SDS). Under optimal CE conditions, separation of the investigated substance was achieved in less than 0.7min. Quality parameters, such as linearity (R2>0.99), precision (RSD<5.41%), detection and quantification limits (3.37 and 11.24mgkg−1 for honey samples) and recovery (96.37–99.56%). The proposed methodology was successfully applied to the analysis of 5-HMF in honey samples. The analytical performance of this method makes it suitable for implementation in food laboratories for the routine determination of 5-HMF in honey samples.
•A rapid CZE method for the analysis ofcitrate, phosphate and sulfitewas developed.•The analytes were separated in less than 3.5 min.•Seafood samples were analyzed by the validated CZE ...method.•In-house method validation was performed to confirm the fitness-for-purpose.
Since seafood is susceptible to decomposition, additives may be used to maintain its quality. However, some additives may be improperly used to disguise spoilage, thus resulting in food fraud. Market growth demands faster and more reliable quality control tools that incorporate the most common additives in a single analysis. This study developed a rapid analytical method for the determination of citrate, phosphate and sulfite in seafood by capillary zone electrophoresis with indirect UV–Vis detection. Electrophoretic separation was achieved in less than 3.5 min. The background electrolyte consisted of 20 mmol L−1 of benzenesulfonic acid and 45 mmol L−1 of aminocaproic acid. After validation, the method was applied for 24 seafood real samples. Citrate was found in five samples. Four samples presented higher phosphate and sulfite concentrations than those permitted by Brazilian legislation. Good analytical performance indicates that the method is a viable alternative for food control in routine analysis.
Although parabens have several features of ideal preservatives, different studies have shown that they may affect human health due to their estrogenic activity. Therefore, various strategies have ...been applied to reduce their skin penetration. However, the effect of paraben combinations on transdermal permeation has not yet been investigated. Thus, the objective of this study was to evaluate paraben permeation in pig ear skin using a Franz diffusion cell system with capillary electrophoresis detection, in order to identify which paraben combinations (defined by a factorial design) have the lowest skin permeation. The permeation of isolated parabens was also evaluated and the permeation characteristics, obtained by the Moser model, confirmed that lipophilicity and molecular weight may influence the systemic absorption of these compounds. In previous tests using isolated parabens, methyl and ethyl parabens presented greater retention in the epidermis compared to the dermis, while propyl and butyl parabens had similar retention profiles in these layers. An increase in ethanol concentration and experimental time promoted greater parabens retention in the dermis compared to the epidermis. The binary combinations of methyl and ethyl parabens as well as of methyl and propyl parabens (added to several cosmetic products in order to increase the antimicrobial spectrum) reduced significantly their permeation rates through pig ear skin (with the exception of EP), probably due to the high retention of these parabens in the epidermis and dermis.
The study systematically investigated the nutritional potential of two different growing populations of Sarcocornia ambigua (salt-tolerant) in terms of nutrients, bioactive compounds, and antioxidant ...activities. The results revealed that the moisture content represented the largest single component (88.15% and 88.57%) in the proximate composition of both samples of S. ambigua. The mineral present in highest amounts in both samples (on a fresh matter basis) was sodium, followed by potassium, magnesium and then calcium. The antioxidant activity for samples measured by DPPH ranged from 34.64 to 135.83μmolTEAC100g−1 and by FRAP from 31.92 to 170.14μmolFe+2100g−1. The fifteen phenolic compounds identified in each extract by HPLC–ESI-MS/MS reveal the presence of one coumarin (scopoletin), one phenolic aldehyde (syringaldehyde), eight phenolic acids (p-coumaric, cinnamic, vanillic, ferulic, caffeic, syringic, sinapic, and chlorogenic acids) and five flavonoids (galangin, quercetin, naringin, kaempferol and isoquercitrin). This information can be useful in determining the possible role of the compounds identified which can participate in the prevention of different health disorders. Further studies are needed to evaluate the bioabsorption and bioavailability of the compounds present in S. ambigua, as well as the interactions between them, after consumption. In summary, the findings of this study highlight the potential of this halophyte as a valuable source of natural antioxidants and nutrients for use in the food and pharmaceutical industries.
•Sodium was the mineral which presented the highest amount in all samples.•HPLC–ESI-MS/MS was employed to detect and quantify phenolic compounds.•22 and 15 phenolic compounds were detected and quantified from extracts of S. ambigua. d) Ferulic and caffeic acids were the major phenolic compounds quantified.•The geographical location of growth, affects the phenolic compounds.
Alzheimer's disease and diabetes mellitus are contemporary diseases of great concern. Phenolic compounds are linked to several health benefits and could lead to novel strategies to combat these ...ailments. The objective of this study was to evaluate by electrophoretically-mediated microanalysis the potential inhibitory activity of the fruit juices from Plinia cauliflora ("jaboticaba") and Eugenia uniflora ("pitanga") toward acetylcholinesterase (AChE) and α-glucosidase, target enzymes in strategies for the treatment of these diseases. The phenolic profiles of the samples were also investigated. Jaboticaba and pitanga juices inhibited 85.90 ± 1.73 and 52.67 ± 1.24% of AChE activity at 5 mg mL
−1
, and 57.91 ± 2.60 and 69.47 ± 2.89% of α-glucosidase activity at 1 mg mL
−1
, respectively. Total phenolic content of the juices were 303.54 ± 28.28 and 367.00 ± 11.42 mgGA L
−1
, respectively. The observed inhibitory activity can be explained, at least in part, by the presence of the phenolic compounds.
Analysis of physicochemical parameters, phenolic compounds, total reducing capacity, free radical scavenging, and antimicrobial potential was performed in 14 samples of honey from six different ...species of stingless bees from Brazil. The results of the physicochemical properties showed high moisture (24.28%–38.20% wt/wt), free acidity above 50 meq/kg for most honey samples, reducing sugars ranging from 58.79% to 73.01% (wt/wt), 5‐hydroxymethylfurfural (5‐HMF) below the limit of quantification (0.074 mg/L), diastase activity from <3 to 70.91 Göthe units, and electrical conductivity values varying from 0.13 to 0.84 mS cm−1. In addition, 12 phenolic compounds were quantified, being taxifolin (<LOD—41.40 µg 100 g−1) and syringaldehyde (<LOD—75.00 µg 100 g−1) the compounds that presented the higher concentrations. The results also showed that the honey has reducing capacity, free radical‐scavenging activity and, presents potential growth inhibitor of Escherichia coli or Staphylococcus aureus. Stingless bee honey can be pointed out as a peculiar product with antioxidants and antibacterial properties.
Practical applications
The Meliponinae form a large group of bees that lack a sting and are found among various tropical and subtropical regions of the world. The honey produced by these bees is a peculiar product due to its physical, chemical, and sensorial characteristics. For these aspects, this honey has been being valued in the world market, and studies about its composition have been conducted. However, the huge variety of species of stingless bee results in honeys with diverse composition, being influenced also by the climate, soil characteristics, flowers, and geographical regions. For this reason, having the knowledge about the composition of honeys from different regions, species, or origins can help in the standardization and regulation of this honey (regulations are nonexistent yet), being able to expand its world market.
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