Sustainable Recovery of Phenolic Compounds from Distilled Rosemary By-Product Using Green Extraction Methods: Optimization, Comparison, and Antioxidant Activity.

Rosemary solid distillation waste (SWR), a by-product of the essential oil industry, represents an important source of phenolic antioxidants. Green technologies such as ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), and accelerated solvent extraction (ASE) of phenolic compounds from SWR were optimized as valorization routes to maximize yield, rosmarinic acid (RMA), carnosol (CARO) and carnosic acid (CARA) contents. Response surface methodology was used in this context, with ethanol concentration (X1), extraction temperature (X2), and time (X3) being the independent variables. A second-order polynomial model was fitted to the data, and multiple regression analysis and analysis of variance were used to determine model fitness and optimal conditions. Ethanol concentration was the most influential extraction parameter, affecting phenolic compounds, while the influence of other parameters was moderate. The optimized conditions were as follows: X1: 67.4, 80.0, and 59.0%, X2: 70, 51, and 125 °C, and X3: 15, 10, and 7 min for MAE, UAE, and ASE, respectively. A comparison of optimized MAE, UAE, and ASE with conventional Soxhlet extraction techniques indicated that ASE provided a higher extraction yield and content of phenolic compounds. However, UAE represented the best process from an environmental point of view, allowing an improved extraction of phenolics from SWR with high energy efficiency and low energy costs.

Determination of tetrabromobisphenol A and its brominated derivatives in water, sediment and soil by high performance liquid chromatography-tandem mass spectrometry.

Tetrabromobisphenol A (TBBPA) was typical brominated flame retardant and potential environmental endocrine disruptor, and it had persistence, bioaccumulation and chronic toxicity. Simultaneous determination of ultra-trace TBBPA, tribromobiphenol A (tri-BBPA), dibromobiphenol A (di-BBPA), monobromobisphenol A (mono-BBPA) and bisphenol A (BPA) was developed by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS), the parent ion charge ratios (m/z) had been optimized. The linear range was wider and the limit of detection was (LOD) 0.09 ~ 0.21 ng mL-1, which could detect trace pollutants. The extraction efficiency was improved by optimizing the parameters, HLB cartridge was used in the water sample by solid phase extraction (SPE), the recovery rates in water samples were over 80.28% with three concentration levels, the relative standard deviations (RSD) were less than 7.12%, and the minimum detection limit of the method was 0.90 ~ 2.10 × 10-3 ng mL-1. Soil and sediment samples were extracted by accelerated solvent extraction (ASE), the recovery rates in soil and sediment were over 79.40% and 75.65%, the minimum detection limit was 0.0225 ~ 0.0525 ng g-1, RSD was less than 7.19%. The proffered method was successfully utilized to detect actual samples, the residue of di-BBPA and mono-BBPA are detected in Naihe River and Shuxi River in Tai'an City, residue of di-BBPA and mono-BBPA was detected in the soil, and there was low residual amount of di-BBPA, mono-BBPA and BPA in the sediment of Shuxi River.

Characterization of potentially health-promoting constituents in sea fennel (Crithmum maritimum) cultivated in the Conero Natural Park (Marche region, Central Italy).

CONTEXT: Sea fennel (Crithmum maritimum L. [Apiaceae]) is an aromatic herb rich in bioactive molecules, such as polyphenols, with potential positive effects on human health. OBJECTIVE: This study aimed at the characterization of sea fennel secondary metabolites, focusing on the phenolic fraction. MATERIALS AND METHODS: Samples of whole sprouts, sole leaves and sole stems were subjected to accelerated solvent extraction with methanol, and the resulting extracts were analyzed by high­performance thin­layer chromatography, high-performance liquid chromatography, and liquid chromatography coupled with diode array detection and high-resolution mass spectrometry (LC-DAD-HRMS). RESULTS: HPTLC and HPLC analyses of sea fennel extracts showed similar chromatographic profiles among the tested samples, and the prevalence of chlorogenic acid within the phenolic fraction was verified. Ten hydroxycinnamic acids, including neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isochlorogenic acid B, isochlorogenic acid A and isochlorogenic acid C, 11 flavonoid glycosides, e.g., rutin, hyperoside, isoquercitrin, two triterpene saponins and two hydroxylated fatty acids, were detected and annotated via liquid chromatography coupled with diode array detection and high-resolution mass spectrometry. DISCUSSION AND CONCLUSIONS: The use of accelerated solvent extraction and LC-DAD-HRMS for the characterization of sea fennel secondary metabolites allowed the annotation of seven compounds newly detected in sea fennel, including triterpene saponins and hydroxylated fatty acids.

[Determination of fluoroacetic acid in human blood and urine by accelerated solvent extraction-ion chromatography-mass spectrometry].

Fluoroacetic acid is a highly polar poison used for rodent control. When ingested by the human body, it seriously damages nerve cells and heart tissues and even causes death by cardiac arrest or respiratory failure. Common detection methods for fluoroacetic acid include gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry, both of which require complex pretreatment methods, such as derivatization. In this study, a method to determine fluoroacetic acid in human blood and urine based on accelerated solvent extraction-ion chromatography-mass spectrometry (ASE-IC-MS) was established. Two pretreatment methods, namely, acetonitrile precipitation and accelerated solvent extraction, were compared. Furthermore, the effects of different extraction conditions, such as the extraction time, extraction temperature, and number of cycles, were investigated. The most suitable chromatographic separation conditions, such as the chromatographic column, column temperature, and elution procedure, were determined, and the MS conditions, such as the collision energy (CE) and declustering potential (DP) of the ion pairs of the target compound, were investigated. Based on the experimental results, the optimal pretreatment methods and detection conditions were obtained, and reliable data were collected. Deionized water was used as the extraction solvent, and blood and urine samples were processed by accelerated solvent extractor. The supernatant was sequentially collected via centrifugal ultrafiltration and 0.22 µm membrane filtration, diluted 50 times, and then injected into the chromatographic column for detection. An Ion Pac AS20 IC column was used for isocratic elution with 15.0 mmol/L KOH solution as the eluent. The effluent was passed through a suppressor and into a triple quadrupole mass spectrometer, which was used to perform MS/MS (ESI-) in multiple reaction monitoring (MRM) mode. The quantitative ion was m/z 77.0>57.0 when the CE and DP were -15.0 eV and -20.0 V, respectively. An external standard method was used for quantitative analysis. The results showed a good linear relationship for fluoroacetic acid in the range of 0.5-500.0 µg/L (r>0.999), with limits of detection (LOD) and quantification (LOQ) of 0.14 and 0.47 µg/L, respectively. The recoveries of fluoroacetic acid in blood and urine were 93.4%-95.8% and 96.2%-98.4%, respectively. The intra-day RSDs for blood and urine were 0.8%-1.6% and 0.2%-1.0%, respectively, while the inter-day RSDs were 2.3%-3.8% and 3.9%-6.9%, respectively. Further investigation revealed that the matrix effects of this method in blood and urine, at -7.4% and -3.0%, respectively, were fairly weak. The established method was successfully applied to detect fluoroacetic acid in human blood and urine obtained from a poisoning case, and the results obtained provided crucial clues that led to swift case resolution. The efficiency of the method was significantly higher than that of conventional detection methods. In conclusion, the developed method has high sensitivity and good repeatability and is suitable for the rapid detection of fluoroacetic acid in human blood and urine. Moreover, because this method does not require derivatization, it is simple and efficient.

[Determination of bisphenols in sediment by accelerated solvent extraction and solid-phase extraction purification coupled with ultra performance liquid chromatography-tandem mass spectrometry].

Bisphenols are endocrine disruptors that are characterized with bioaccumulation, persistence, and estrogenic activity. Even low contents of bisphenols can exert adverse effects on human health and the ecological environment. Herein, a method combining accelerated solvent extraction and solid-phase extraction purification with ultra performance liquid chromatography-tandem mass spectrometry was developed for the accurate detection of bisphenol A (BPA), bisphenol B (BPB), bisphenol F (BPF), bisphenol S (BPS), bisphenol Z (BPZ), bisphenol AF (BPAF), and bisphenol AP (BPAP) in sediments. The mass spectrometric parameters of the seven bisphenols were optimized, and the response values, separation effects, and chromatographic peak shapes of the target compounds were compared under three different mobile phase conditions. The sediment samples were pretreated by accelerated solvent extraction, and orthogonal tests were used to optimize the extraction solvent, extraction temperature, and cycle number. The results showed that the use of 0.05% (v/v) ammonia and acetonitrile as the mobile phase for gradient elution could rapidly separate the seven bisphenols on an Acquity UPLC BEH C18 column (100 mm×2.1 mm, 1.7 µm). The gradient program was as follows: 0-2 min, 60%A; 2-6 min, 60%A-40%A; 6-6.5 min, 40%A; 6.5-7 min, 40%A-60%A; 7-8 min, 60%A. Orthogonal experiments indicated that the optimal extraction conditions were as follows: extraction solvent of acetonitrile, extraction temperature of 100 ℃, and cycle number of three. The seven bisphenols showed good linearity in the range of 1.0-200 µg/L, with correlation coefficients (r2) greater than 0.999, and the limits of detection were 0.01-0.3 ng/g. The recoveries for the seven bisphenols ranged from 74.9% to 102.8% at three spiking levels (2.0, 10, 20 ng/g), with relative standard deviations ranging from 6.2% to 10.3%. The established method was applied to detect the seven bisphenols in sediment samples collected from Luoma Lake and its inflow rivers. BPA, BPB, BPF, BPS, and BPAF were detected in the sediments of the lake, and BPA, BPF, and BPS were detected in the sediments of its inflow rivers. The detection frequency of BPA and BPF was 100%, and the contents of these bisphenols in the sediment were 11.9-38.0 ng/g and 11.0-27.3 ng/g, respectively. The developed method is simple, rapid with high accuracy and precision, and is suitable for the determination of the seven bisphenols in sediment.

Pressurized Liquid Extraction: A Powerful Tool to Implement Extraction and Purification of Food Contaminants.

Pressurized liquid extraction (PLE) is considered an advanced extraction technique developed in the mid-1990s with the aim of saving time and reducing solvent with respect to traditional extraction processes. It is commonly used with solid and semi-solid samples and employs solvent extraction at elevated temperatures and pressures, always below the respective critical points, to maintain the solvent in a liquid state throughout the extraction procedure. The use of these particular pressure and temperature conditions changes the physicochemical properties of the extraction solvent, allowing easier and deeper penetration into the matrix to be extracted. Furthermore, the possibility to combine the extraction and clean-up steps by including a layer of an adsorbent retaining interfering compounds directly in the PLE extraction cells makes this technique extremely versatile and selective. After providing a background on the PLE technique and parameters to be optimized, the present review focuses on recent applications (published in the past 10 years) in the field of food contaminants. In particular, applications related to the extraction of environmental and processing contaminants, pesticides, residues of veterinary drugs, mycotoxins, parabens, ethyl carbamate, and fatty acid esters of 3-monochloro-1,2-propanediol and 2-monochloro-1,3-propanediol from different food matrices were considered.

Dataset of atmospheric concentrations of polycyclic aromatic hydrocarbons in the Memphis Tri-state Area.

This dataset contains concentrations (in ng/m3) of 32 polycyclic aromatic hydrocarbons (PAHs) in the ambient air in the Memphis Tri-state Area (MTA). In the atmosphere, PAHs are toxic pollutants emitted from incomplete combustion sources. This monitoring campaign was conducted at 19 sites in three neighboring counties in Tennessee, Mississippi, and Arkansas, i.e., MTA, over one year. The monitoring sites represented industrial, urban, suburban, and remote land types. Total suspended particulate (TSP) samples were collected at each site using a high-volume sampler every 12 days from March 13th, 2018, to May 25th, 2019. The collection media consisted of a quartz fiber filter (QFF) and a glass thimble containing polyurethane foam (PUF) and XAD-4 resin that collected particulate- and gas-phase PAHs. Approximately 288 m3 of ambient air was drawn over 24 h. The QFF and sorbents were extracted together in an accelerated solvent extraction (ASE) system, and the extract was then nitrogen blown down to 1 ml in an automatic evaporator, and the final extract was analyzed for 32 target PAHs on a gas chromatography/mass spectrometry (GC/MS) system operated in the select-ion-monitoring (SIM) mode. The US Environmental Protection Agency (EPA) reviewed and approved the sampling and analytical protocols. The dataset also has site descriptions, sampling information, and analytical performance. This PAH dataset can be used to explore atmospheric chemistry and sources of PAHs, estimate population exposures to airborne PAHs and the associated health risks, and address environmental health disparities.

Intensifying Effect of Instant Controlled Pressure Drop (DIC) Pre-Treatment on Hesperidin Recovery from Orange Byproducts: In Vitro Antioxidant and Antidiabetic Activities of the Extracts.

The orange byproduct is a widely accessible and valuable source of functional phenolic compounds, particularly hesperidin. Hesperidin extraction remains a challenging phase in its valorization chain due to its low solubility and limited extractability in solvents. This work aims to examine the effect of conventional solvent extraction (CSE) compared to emerging and innovative extraction methods: accelerated solvent extraction (ASE) and ultrasound-assisted extraction (UAE) when applied with or without a pretreatment process of instant controlled pressure drop (DIC) to intensify extraction, antioxidant, and antidiabetic activities. The total phenols, flavonoids, hesperidin contents, radical scavenging activities, iron chelating activity, and in vitro α-amylase inhibition of the extracts were determined for CSE (80%, 70 °C), UAE (ethanol 80%, 70 °C, 200 W), and ASE (ethanol 60%, 100 °C, 100 bars) with or without DIC pretreatment (pressure = 0.4 MPa, total thermal time = 30 s). The hesperidin amounts obtained were 0.771 ± 0.008 g/100 g DM, 0.823 ± 0.054 g/100 g DM, and 1.368 ± 0.058 g/100 g DM, for CSE, UAE, and ASE, respectively. DIC pretreatment of orange byproducts increased hesperidin recovery by 67%, 25.6%, and 141% for DIC-CSE, DIC-UAE, and DIC-ASE, respectively. The DPPH and ABTS radical scavenging and iron chelating activities of extracts were also significantly enhanced, and the in vitro antidiabetic activity of extracts was preserved.

Edible Plant Extracts against Aedes aegypti and Validation of a Piper nigrum L. Ethanolic Extract as a Natural Insecticide.

The Aedes aegypti mosquito significantly impacts public health, with vector control remaining the most efficient means of reducing the number of arboviral disease cases. This study screened the larvicidal and pupicidal activity of common edible plant extracts. Piper nigrum L. (black pepper) extract production was optimized using accelerated solvent extraction (ASE) and validated following regulatory requirements using HPLC-PDA analytical methodology to quantify its major component-piperine. Larvicidal activity was determined for the standardized P. nigrum fruit ethanol extract (LC50 1.1 µg/mL) and piperine standard (LC50 19.0 µg/mL). Furthermore, 9-day residual activity was determined for the extract (4 µg/mL) and piperine (60 µg/mL), with daily piperine quantification. Semi-field trials of solid extract formulations demonstrated 24-day activity against Ae. aegypti larvae. Thus, the standardized P. nigrum extract emerges as a potential candidate for insecticide development to control the arboviral vector.

Optimization of Accelerated Solvent Extraction of Ginsenosides from Cultivated Wild Ginseng Using Response Surface Methodology.

This study's aim is to apply response surface methodology (RSM) to model and optimize the accelerated solvent extraction (ASE) technique for extracting the sum of ginsenosides (Rg1, Rb1, and Rg3) and total ginsenosides from cultivated wild ginseng. To extract ginsenosides from cultivated wild ginseng, a new ASE-based method, combined with RSM modeling and optimization, was developed. The RSM method, which was based on a five-level, three-factor central composite design, was used to obtain the optimal combination of extraction conditions. Briefly, the optimal extraction conditions for the sum of ginsenosides (Rg1, Rb1, and Rg3) and total ginsenoside were as follows: 88.64% ethanol for each extraction solvent, 105.98°C and 129.66°C of extraction temperature, 28.77 and 15.92 min of extraction time, extraction pressure of 1,500 psi, nitrogen purge of 60 s, flush volume of 60%, and one extraction cycle. A 3D response surface plot and contour plot derived from the mathematical models were applied to obtain the optimal conditions. Under the above conditions, the experimental extraction yields of the sum of ginsenosides (Rg1, Rb1, and Rg3) and total ginsenoside content were 7.45 and 32.82 mg/g, respectively, which closely agrees with the model's prediction values.

Optimization and comparison of nonconventional extraction techniques for soluble phenolic compounds from brocade orange (Citrus sinensis) peels.

Brocade orange (Citrus sinensis L. Osbeck) peels (BOPs) are rich in a variety of phenols with multiple and strong bioactivities. This study sought to utilize a response surface methodology to optimize the parameters of accelerated solvent extraction (ASE) to obtain phenolic extracts from BOPs. Total phenolic and flavonoid content (TPC and TFC), profiles, and antioxidant activities of extracts for free, esterified-, and glycosylated-bound phenols from ASE were compared with those derived from Soxhlet extraction (SE) (80°C, 6 h) and heat-reflux extraction (HRE) (80°C, 3 h). Maximum practical TPC and TFC under optimal ASE conditions (15 min, 108°C, 82 bar, and three cycles) were determined to be 32.82 mg gallic acid equivalents/dry weight (DW) and 10.25 mg rutin equivalents/DW, respectively. The profiles, contents, and corresponding bioactivities of the extracts significantly depended on extraction method, particularly with regard to phenolic fraction. Generally, ASE and HRE were associated with higher levels of extraction efficiency and higher quality targeted bioactive compounds with stronger antioxidant activity. More importantly, ASE represents a simple, efficient, and time-saving technique for the extraction of phenols. Furthermore, the finding that different phenolic fractions contain variable profiles and contents of phenols is useful for efforts to obtain targeted individual bioactive ingredients and make better use of biomass residues.

The Determination of Polycyclic Aromatic Hydrocarbons (PAHs) with HPLC-DAD-FLD and GC-MS Techniques in the Dissolved and Particulate Phase of Road-Tunnel Wash Water: A Case Study for Cross-Array Comparisons and Applications.

Accelerated solvent extraction (ASE) and solid phase extraction (SPE) protocols tailored to either gas chromatography mass spectrometry (GC-MS) or high-performance liquid chromatography coupled to diode-array and fluorescence detection (HPLC-DAD-FLD) were developed for the determination of EPA 16 polycyclic aromatic hydrocarbons (PAHs) in the particulate and dissolved phase of road-tunnel wash water. An analytical approach was developed, assessed, and applied on environmental samples collected from five road tunnels in Norway. The absolute recoveries ranged from 57 to 104% for the particulates, and from 42 to 79% for the dissolved water phase. The target PAH compounds were separated in 34.75 min using the GC method and in 22.50 min by HPLC. In the particulate phases, higher molecular weight PAHs were detected in the range of 0.043 to 0.93 µg/g, and lower molecular weight PAHs were detected in the range of 0.020 to 1.0 µg/g, while the intermediate ones were present in the range of 0.075 to 2.0 µg/g. In contrast to the particulates, the dissolved phase mainly contained lower molecular weight PAHs in the range of 0.0098 to 0.50 µg/L. GC-MS demonstrated lower detection limits (LODs) than HPLC-DAD-FLD for 13 out of the 16 PAHs. A cross-array comparison of the two analytical techniques indicated that some target PAHs were detected solely or in higher concentrations with HPLC-DAD-FLD, indicating the occurrence of false positive peaks or/and co-eluting components. The resulting concentrations in the road tunnel wash water samples were used to calculate specific PAH forensic ratios to pinpoint the potential sources of PAH pollution. These ratios revealed that there are several potential sources for the origin of PAHs in tunnel wash water.

Determination of pesticides and their degradation products in sediment samples by accelerated solvent extraction and solid-phase extraction with high-performance liquid chromatography-high-resolution mass spectrometry.

A new sensitive and selective methods was developed to quantify different types of pesticides and their degradation products in sediment. The method developed was optimized and modified based on the accelerated solvent extraction, followed by the solid-phase extraction clean-up technique. High-performance liquid chromatography coupled with mass spectrometry was used for analysis. The influence of various parameters on the extraction process was investigated, including the extraction temperature, extraction solvent, purification column and purification solvent, etc. Under the optimal conditions, the relative recoveries of the pesticides and their degradation products ranged from 80 to 106% for spiked blank sediment and environmental sediment samples with relative standard deviations of 1-9%. The method displayed low method detection limits for both sediment matrices and achieved good linearity over the tested range of concentrations. The physical and chemical properties of sediment showed that high content of sediment water content and humic acid would affect the extraction efficiency of sample pretreatment. The method was applied to environmental sediment to quantify pesticide residues in the samples. Based on the instrument and method performance validation results, the developed methods can be applied in environmental pesticide residue analysis, thus providing a scientific method for the detection of sediment samples.

Optimization of accelerated solvent extraction of ellagitannins in black raspberry seeds using artificial neural network coupled with genetic algorithm.

This study aimed to identify ellagitannins in black raspberry seeds (BRS) and to optimize accelerated solvent extraction of ellagitannins using an artificial neural network (ANN) coupled with genetic algorithm. Fifteen monomeric and dimeric ellagitannins were identified in BRS. For ANN modeling, extraction time, extraction temperature, and solvent concentration were set as input variables, and total ellagitannin content was set as output variable. The trained ANN had a mean squared error value of 0.0102 and a regression correlation coefficient of 0.9988. The predicted optimal extraction conditions for maximum total ellagitannin content were 63.7% acetone, 4.21 min, and 43.9 °C. The actual total ellagitannin content under the optimal extraction conditions was 13.4 ± 0.0 mg/g dry weight, and the prediction error was 0.75 ± 0.27%. This study is the first attempt to analyze the composition of ellagitannins in BRS and to determine optimal extraction conditions for maximum total ellagitannin content from BRS.

Optimization Extraction and Antioxidant Activity of Crude Polysaccharide from Chestnut Mushroom (Agrocybe aegerita) by Accelerated Solvent Extraction Combined with Response Surface Methodology (ASE-RSM).

The present work is conducted to investigate the optimal extraction technology of polysaccharide from chestnut mushroom (Agrocybe aegerita) using a new method based on accelerated solvent extraction combined with response surface methodology (ASE-RSM). The conventional reflux extraction (CRE) method and ultrasonic-assisted extraction (UAE) method were also carried out. Additionally, the in vitro antioxidant activities, including ABTS and DPPH assay, were evaluated. The RSM method, based on a three level and three variable Box-Behnken design (BBD), was developed to obtain the optimal combination of extraction conditions. In brief, the polysaccharide was optimally extracted with water as extraction solvent, extraction temperature of 71 °C, extraction time of 6.5 min, number of cycles of 3, and extraction pressure of 10 MPa. The 3D response surface plot and the contour plot derived from the mathematical models were applied to determine the optimal conditions. Under the above conditions, the experimental value of polysaccharide yield was 19.77 ± 0.12%, which is in close agreement with the value (19.81%) predicted by the model. These findings demonstrate that ASE-RSM produce much higher polysaccharide and consumed environmentally friendly extraction and solvent systems, have less extraction discrimination and shorter time and provide scientific basis for industrialization of polysaccharide extraction. Moreover, it was proved that the polysaccharide had the potential ability to scavenge ABTS and DPPH.

[Determination of 82 polychlorinated biphenyls in biological samples using accelerated solvent extraction-isotope dilution-high resolution gas chromatography-high resolution mass spectrometry].

In China, the detection methods for polychlorinated biphenyls (PCBs) in aquatic products are mainly effective for 6 indicative PCBs and 12 coplanar dioxin-like PCBs, which only account for a limited proportion of PCBs in organisms. In this study, to obtain the detailed concentration levels of PCBs in organisms, elucidate the metabolism and enrichment characteristics of PCBs in organisms, and accurately evaluate the exposure level and risks of PCBs to humans, an improved method for the simultaneous determination of 82 PCBs in fish and shellfish samples was developed using isotope dilution-high resolution gas chromatography-high resolution mass spectrometry (ID-HRGC-HRMS). The recovery and reproducibility of two extraction methods, i. e., oscillatory extraction and accelerated solvent extraction (ASE), were compared. Finally, ASE was chosen for subsequent experiments. Specifically, after adding 1 ng13C-labeled extraction internal standards, the samples were extracted under pressure by ASE using a mixture of n-hexane-dichloromethane (1∶1, v/v). The experimental conditions employed for this were a pressure of 10.3 MPa, heating temperature of 100 ℃, heating time of 5 min, static time of 8 min, flush volume of 60%, purging time of 120 s, and 34 mL cells. Subsequently, the extracts were loaded on an 8 g acid silica gel (44%) column (inner diameter: 15 mm) and eluted with 90 mL of n-hexane. After purification and concentration, the analytes were determined by HRGC-HRMS with a fused-silica capillary column (DB-5MS, 60 m×0.25 mm×0.25 µm). The temperature program was optimized to separate the most target compounds at the baseline. Specifically, the initial oven temperature was 120 ℃, which was held for 1 min, following by heating to 180 ℃ at 30 ℃/min, heating to 210 ℃ at 2 ℃/min and holding for 1 min, and further heating to 310 ℃ at 2.5 ℃/min and holding for 1 min. The injector and ion source temperatures were 270 ℃ and 280 ℃, respectively. With a static resolution of 10000, the HRMS instrument was operated in the selected-ion monitoring mode at an electron energy of 35 eV. The 82 PCBs were qualified by their retention time and two characteristic ions, and thereafter quantified using the mean relative corresponding factor (RRF). The results showed that the relative standard deviation (RSD) of the RRF obtained from six-point calibration standard solutions was less than 20%. The linearity ranges were from 0.1 to 200 µg/L, and the correlation coefficients (r2) were greater than 0.99. Under optimum conditions, the method detection limits (MDLs) for the PCBs of biological samples were in the range of 0.02-3 pg/g. To validate the method, the fish and shellfish samples were spiked with a low level (0.4 ng) and high level (3.6 ng) of native PCB standards. The spiked recoveries using low-concentration native PCBs were 71.3%-139% in fish and 76.9%-143% in shellfish, and the RSDs (n=7) were 2.1%-14% and 4.5%-14%, respectively. The spiked recoveries using high-concentration native PCBs were 77.6%-141% and 82.2%-131%, respectively, and the RSDs (n=7) were 1.4%-9.4% and 1.7%-11%, respectively. An analysis of fresh fish and shellfish samples showed that the contents of a single PCB ranged from "not detected" to 54.1 pg/g, where 12 coplanar dioxin-like PCBs were detected in the range of 12.6 pg/g to 74.5 pg/g, six indicative PCBs in the range of 30.9 pg/g to 62.1 pg/g, and 82 PCBs in the range of 174 pg/g to 672 pg/g. It was concluded that this method could be successfully applied for the determination of PCBs in biological samples with good accuracy and precision. This comprehensive analytical method of PCBs in aquatic products provides effective technical support for biological monitoring; it will also aid in ecological and environmental management and the implementation of the Stockholm Convention policies.

Extraction and analysis of an organophosphate salt nucleating agent from irradiated polypropylene resin.

Although it is well-established that irradiation of produce can reduce food-borne pathogens and spoilage organisms, data on the effect of irradiation on polymer additives in food packaging materials are limited, particularly for those additives used in packaging leafy greens or in current food packaging materials. We investigated the effects of irradiating a nucleating agent, aluminium, hydroxybis[2,4,8,10-tetrakis(1,1-dimethylethyl)-6-hydroxy-12H-dibenzo [d,g][1,3,2]dioxaphosphocin 6-oxidato]- (CAS Reg. No. 151841-65-5), at doses of 1-20 kGy in polypropylene. That nucleating agent was then extracted using accelerated solvent extraction and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), liquid chromatography-photodiode array detection (LC-PDA), and solid-state nuclear magnetic resonance (SSNMR) spectroscopy. We found this nucleating agent was not significantly affected by radiation treatment up to 20 kGy. Therefore, this nucleating agent could potentially be useful in food packaging materials that will be irradiated at doses of 20 kGy or less. Establishing which additives are stable under anticipated irradiation doses will help support safety evaluation of food packaging materials.

Characterization of the Key Aroma Constituents in Fried Tilapia through the Sensorics Concept.

The object of this study was tilapia fish that were fried in soybean oil. Volatile compounds were extracted from the fish by ASE-HVE and were studied by GC-O-MS and the AEDA analysis method. A total of 30 aroma compounds were initially determined, and these compounds contribute to the aroma of fried tilapias. The key volatile compounds in fried tilapia were quantitatively analyzed by GC-MS, and the volatile compounds in soybean-fried tilapia were studied by flavor recombination and deletion experiments. Trimethylamine, hexanal, 2,3-dimethylpyrazine, dimethyl trisulfide, trans-2-octenal, 2,3-dimethyl-5-ethylpyrazine, (E)-2-nonenal, 2-propyl-pyridine, and (E,E)-2,4-decadienal were finally determined to be the key volatile compounds in soybean-fried tilapia.

[Pollution Characteristics and Health Risk Assessment of Perfluorinated Compounds in PM2.5 in Zhejiang Province].

As typical new pollutants, perfluorinated compounds (PFCs) have been widely concerned by environmental workers in recent years. This study was carried out to investigate the pollution characteristics of perfluorinated compounds in atmospheric particulate matter (PM2.5) in Zhejiang Province. The chemical extraction of PM2.5 was performed using the accelerated solvent extraction (ASE) method with mixed dichloromethane and acetone (2:1). The chemical analysis was implemented by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The results showed that the daily average concentration of the sum of 12 PFCs (Σ12 PFCs) ranged from 131.63 pg·m-3 to 578.53 pg·m-3, which was slightly higher in winter compared to that in autumn. The concentrations of perfluorosulfonic acids (PFSAs) were much lower than those of perfluorocarboxylic acids (PFCAs). PFOS was the primary contaminant among PFASs, with an average concentration of 12.90 pg·m-3. The content of PFCAs exhibited a trend of PFOA>PFHxA>PFHpA, and the detection rate of long-chain PFCs was much lower than that of short-chain PFCs. The hysplit-4 model was used to calculate the QZ air mass transport trajectory. The results indicated that the backward trajectory of this point was significantly different along time, and the source of air mass rarely affected the concentration. The forward trajectory confirmed that PFCs can be transmitted over long distances in the atmosphere in a short time. The correlation coefficient between PFUdA and PFTeDA was evaluated to be 0.68, and that between PFHxS and PFOS was 0.66, suggesting the same sources of these chemicals. The content of PFCs was positively correlated with PM2.5, indicating that people might suffer from higher health risks on haze days. The risk quotient estimation implied no health risk of PFCs in PM2.5 in Zhejiang Province.

Optimization of the Accelerated Solvent Extraction of Caffeoylquinic Acids from Forced Chicory Roots and Antioxidant Activity of the Resulting Extracts.

Forced chicory roots (FCR) are the main but also the least valued by-products of Belgian endive culture. However, they contain molecules of interest for industry such as caffeoylquinic acids (CQAs). This study aims to investigate accelerated solvent extraction (ASE) as a green technique to recover chlorogenic acid (5-CQA) and 3,5-dicaffeoylquinic acid (3,5-diCQA), the main CQAs. A D-optimal design was used to determine the influence of temperature and ethanol percentage on their extraction. Optimal extraction conditions were determined using response surface methodology (RSM) and allow the recovery of 4.95 ± 0.48 mg/gDM of 5-CQA at 107 °C, 46% of ethanol and 5.41 ± 0.79 mg/gDM of 3,5-diCQA at 95 °C, 57% of ethanol. The antioxidant activity of the extracts was also optimized by RSM. The highest antioxidant activity was achieved at 115 °C with 40% ethanol (more than 22mgTrolox/gDM). Finally, correlation between the antioxidant activity and the amount of CQAs was determined. FCR can be a great source of bioactive compounds with potential use as biobased antioxidant.