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A simple and effective ultrasound-assisted dispersive micro solid-phase extraction (UA-dμSPE) method was developed for the spectrophotometric determination of traces maneb in food and water. In this study, a new hybrid block copolymer poly (vinyl benzyl chloride-b-dimethyl aminoethyl methacrylate) (Pvb-DMA) was synthesized and characterized using techniques such as FTIR, SEM-EDX. The synthesized Pvb-DMA was used as an adsorbent for the extraction of maneb for first time in this study. The effects of different experimental variables such as pH, adsorbent amount, sample volume, eluent type were optimized. The statistical toll factorial design was applied to estimate the individual and combined impact of parameters on the extraction of maneb. The applicability of different solvents such as acetone, methanol, ethanol, tetrahydrofuran, acetonitrile for maneb recovery from adsorbent was tested. The detection and quantification limits were found to be 3.3 ng mL−1 and 10.0 ng mL−1, respectively. In addition, the preconcentration factor and linear range was obtained 300 and 10–500 ng mL−1. The extraction recovery and relative standard deviation were found to be 95 % and 2.8 %, respectively. [Display omitted] • A low-cost, simple, green and selective ultrasound-assisted dispersive micro solid phase extraction (dμSPE) was developed. • A block copolymer (Pvb-DMA) was synthesized and used as adsorbent for the first time. • Extraction factors were optimized using central composite design, saving time and chemical consumption. • The developed dμSPE technique provided low LOD, LOQ, RSD and high PF. • Present method was applied to maneb determination in water and food samples. [ABSTRACT FROM AUTHOR]

One of the principal byproducts of coffee roasting is the coffee parchment. It is abundant in bioactive substances, including derivatives of chlorogenic acids, which are well-known for their exceptional antioxidant effects. It is advantageous to use environmentally friendly extraction techniques on such residues since it adds value to the entire coffee production process supply chain. The aim of this work was to assess and enhance the ability of non-conventional extraction techniques to extract derivatives of chlorogenic acid from coffee parchment. A central composite design was used to maximize the recovery of those phenolic compounds. The optimized extraction conditions were with 5 min extraction period, at a temperature of 70 °C, and 80% ethanol in the extractor solvent. In this conditions extraction recovery of chlorogenic acids was of 0.8% by the use of microwave-aided extraction (MAE). The optimized conditions are practical, economical, and ecologically friendly method to extract phenolic compounds and, consequently, underscores the potential for sustainable utilization of coffee parchment, offering a valuable contribution to the development of environmentally conscious strategies within the coffee industry. • Coffee parchment is a rich source of phenolic compounds including chlorogenic acids. • Chlorogenic acids extraction method was optimized by Central Composite design • Microwave-Assisted Extraction presented a yield of 0.8% chlorogenic acids. • The optimized conditions included 5 min extraction at 70 °C, with 80% ethanol. • The optimized method can add value to the coffee chain production. [ABSTRACT FROM AUTHOR]

In this study, a cheap, fast and simple orbital shaker-assisted fatty acid-based switchable solvent microextraction (OS-FASS-ME) procedure was developed for the extraction of amoxicillin (AMOX) in dairy products, pharmaceutical samples and wastewater prior to its spectrophotometric analysis. Fatty acid-based switchable solvents were investigated for extracting AMOX. The key factors of the OS-FASS-ME procedure were optimized using a central composite design. The linearity of OS-FASS-ME procedure was in the range 5–600 ng mL−1 with a correlation coefficient of 0.991. In five replicate experiments for 20 ng mL−1 of AMOX solution, the recovery and relative standard deviation were 95.8% and 2.2%, respectively. Limits of detection and quantification were found 1.5 ng mL−1 and 5 ng mL−1, respectively. The accuracy, precision, robustness and selectivity of the OS-FASS-ME procedure were investigated in detail under optimum conditions. The OS-FASS-ME procedure was applied to milk, cheese, wastewater, syrups and tablets. A comparison of the results obtained from the reference method and the OS-FASS-ME method showed that the OS-FASS-ME procedure can be successfully applied to complex matrices. • Fatty acid-based switchable solvents were investigated for extraction of amoxicillin. • The optimized procedure does not include heating and centrifugation steps. • The linearity was in the range of 5–600 ng mL−1 (R2:0.991). • The LOD of the method was 1.5 ng mL−1 with an extraction time of 3.5 min. [ABSTRACT FROM AUTHOR]

A new magnetic nano gel (MNG) was prepared from choline chloride/phenol deep eutectic solvent and magnetic amberlite XAD-7 nanocomposite. The dispersive solid phase micro extraction (dSPME) method was developed for seperation and preconcentration of Brilliant Blue FCF (BB) by the prepared MNG. In this study, firstly, the optimum DES type and mole ratio of DES were investigated before response surface methodology optimization. Then, the effect of the MNG-dSPME experimental parameters were optimized by response surface methodology using central composite design. Under the optimum microextraction conditions, limit of detection (LOD), limit of quantification (LOQ), preconcentration factor (PF), enhencament factor (EF) were found to be 1.15 μg L−1,3.80 µg L-1, 70, and 88, respectively. It was seen that the recovery of real samples were obtained from 95.5 to 103.6%. The pesent method was succesfully for extraction of BB in some food, personal care samples, to the best of our knowledge, this is the first study that is presented method on determination of BB by preconcentration with magnetic nano gel. The obtained results showed that the present procedure is effective, sensitive, and has high accuracy for the quantitative detection of BB. • A new nanogel was obtained from magnetic nanoparticle and deep eutectic solvent. • A magnetic nanogel-based dispersive solid phase microextraction (MNG-dSPME) method was developed • Factorial design was used to optimize MNG-dSPME method. • This method was used for the first time for dispersive solid phase microextraction of BB. [ABSTRACT FROM AUTHOR]

In this paper, a green, cost-effective sample preparation method based on air assisted liquid phase microextraction (AA-LPME) was developed for the simultaneous extraction of As(III) and Sb(III) ions from vegetable samples using hydrophilic/hydrophobic natural deep eutectic solvents (NADESs). Central composite design was used for the optimization of extraction factors including NADES volume, extraction cycle, pH, and curcumin concentration. Limits of detection for As(III) and Sb(III) were 1.5 ng L−1 and 0.06 ng L−1, respectively. Working ranges for As(III) and Sb(III) were 0.2–300 ng L−1 (coefficient of determination (R2 = 0.9978) and 5–400 ng L−1 (R2 = 0.9996), respectively. Relative standard deviations for As(III) and Sb(III) were 2.2–2.8% and 2.9–3.2%, respectively. Enrichment factor of the method was 184 for As(III) and 172 for Sb(III). The accuracy and precision of the AA-NADES-LPME method were investigated by intraday/interday studies and standard reference material analysis, respectively. Finally, the AA-NADES-LPME method was successfully applied to microwave digested vegetable samples using the standard addition approach and acceptable recoveries were achieved. [Display omitted] • α-terpineol and octanoic acid-based NADES was prepared as extraction solvent. • The microextraction step was faster and did not require centrifugation and heating step. • The interaction between analytes and ligand was explained by computational study. • The method showed high sensitivity for As(III) and Sb(III). [ABSTRACT FROM AUTHOR]

[Display omitted] • An acid–induced dispersive liquid–liquid microextraction is developed. • Analytes are extracted by in situ formation of deep eutectic solvents with formed fatty acids. • The method is successfully used for detection of bisphenol A and alkylphenols. • The method is simple, rapid, sensitive, low cost, and environmentally friendly. • The new method expands the application pathway and scope of deep eutectic solvents. This study describes the development of an acid induced dispersive liquid–liquid microextraction method based on the in situ formation of hydrophobic deep eutectic solvents for the extraction of bisphenol A and alkylphenols from environmental water and beverage samples. Hydrochloric acid altered the hydrophilic-hydrophobic state of fatty acid salts to obtain hydrophobic fatty acids, which formed hydrophobic deep eutectic solvents with analytes in situ to extract the analytes. Under optimized conditions, the limits of detection and limits of quantitation were 0.03–0.1 μg L-1 and 0.12–0.3 μg L-1, the intraday and interday relative standard deviations were less than 3.9 %, and the enrichment factor was 29–32. The recoveries of bisphenol A and alkylphenols were 95.9–104.9 % and 86.9–105.0 %, respectively. The extraction process used only hydrochloric acid and fatty acid salts, and the extraction process required less than 1 min. This method has the advantages of simplicity, speed, low cost and environmental friendliness. [ABSTRACT FROM AUTHOR]

• Encapsulation efficiency of Isoleucine-Proline-Proline in vesicles was maximized. • Ethanol injection-microchannel method led to narrow size distribution. • Functional beverages containing niosomes exhibited storage stability. • Niosomes could effectively mask bitterness in functional beverages. In this study, the efficiency and practical utilization feasibility of niosomal and liposomal nanovesicles loading Isoleucine-Proline-Proline (IPP) as suitable ingredients of functional beverages were evaluated. Vesicles were tailored by different preparation methods using phospholipid and non-ionic surfactants. The optimization process was performed by central composite design approach. The results of Fourier transform infrared spectroscopy demonstrated the compatibility of IPP with the vesicles. The phospholipidic nanovesicles, produced by modified ethanol injection-microchannel technique, were smaller with lower polydispersity index than non-ionic surfactant vesicles developed by the method of thin film hydration and probe sonication. However, niosomal model functional beverage exhibited more proper palatability, biological activity and physicochemical properties during long-term storage than liposomal one. Moreover, niosomes exhibited more sustained release behaviour in simulated blood fluid than liposomes. These findings are of great importance for design and development of the functional foods containing IPP. [ABSTRACT FROM AUTHOR]

Highlights • Ultrasound-assisted saponification and LLE were used to extract targets from oil. • Conditions of saponification were optimized by using central composite design. • Simultaneous determination of tocopherols, carotenoids and phytosterols were proposed. Abstract A method was developed to simultaneously determine eight bioactive compounds in edible oil based on ultrasound-assisted saponification, liquid-liquid extraction and liquid chromatography coupled with tandem mass spectrometry. Central composite design was employed to optimize ultrasonic temperature and time of saponification. Sample treatment was conducted by ultrasound-assisted saponification at temperature of 75 °C for 40 min. Limits of detection and limits of quantification ranged from 2.0 to 3.2 and from 6.1 to 10.0 ng/mL, respectively. Linear correlations were obtained (R2 > 0.99) and the recoveries at three spiked levels were between 81.7% and 112.0%. This method was employed to determine eight compounds in camellia oils and olive oils. As results, the contents of stigmasterol, δ-tocopherol, γ-tocopherol, β-carotene and lutein in camellia oils were significantly higher than those in olive oils (p < 0.05). The proposed method can be successfully used to determination of these eight active compounds in camellia oil and other edible oils. [ABSTRACT FROM AUTHOR]

Highlights • Chemometric techniques employed for optimization in food analysis are shown. • Description, advantages, and drawbacks of the experimental designs are presented. • A comparison between the response surface methodologies for food analysis has been performed. Abstract This work presents a critical review of multivariate techniques employed for optimization of methods developed in food analysis. A comparison between the response surface methodologies has been performed, it evidencing advantages and drawbacks of these. Applications of the main chemometric tools (central composite and Box Behnken designs and Doehlert matrix) often utilized for optimization of sample preparation procedures and also instrumental conditions of analytical techniques for determination of organic and inorganic species in food samples are shown. Also, a brief discussion on the use of multiple responses and robustness test in food analysis has been presented. [ABSTRACT FROM AUTHOR]

Highlights • HS-SPME-GC-MS methodology to quantify carbonyl compounds in Port wines. • Optimization and validation of the method was performed. • Optimal SPME conditions were assessed using a central composite design. • Port categories wines were characterized by different carbonyl compound profile. • Old Tawny Port wines showed the highest level of carbonyl compounds. Abstract A method based on headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-triple quadrupole/mass spectrometry detection (GC-TQ/MS) with a prior derivatization step with O -(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA) was developed to quantify carbonyl compounds in different categories of Port wines. Optimal extraction conditions were obtained incubating 2 ml of wine with 2.3 g/l of PFBHA for 10 min and extracted during 20 min at 32 °C. The method was validated for 38 carbonyl compounds (alkanals, alkenals, Strecker aldehydes, dialdehydes, ketones and furan aldehydes) with regard to linearity, repeatability, inter and intra-day precision and accuracy, showing that the method is suitable for the determination of carbonyl compounds in wines. Tawny wines with ‘indication of age’ (10–40 years old) presented the highest levels of some carbonyl compounds, such as propanal, pentanal, hexanal, Strecker aldehydes, diacetyl, methyl glyoxal, 3-pentanone and 2-furfural, whereas Ruby wines were characterized by the highest amounts of some unidentified compounds. [ABSTRACT FROM AUTHOR]

The aim of this study was to establish a new dispersive liquid-liquid microextraction (DLLME) technique for the determination of iron concentration in aqueous solutions and fruit juices based on the reaction between iron and 3-hydroxy-1-(3-hydroxyphenyl)-2-methylpyridin-4(1H)-one (3-OH-PMPO) as a chelating agent. A central composite design (CCD) was applied to optimize the effects of independent parameters (pH, volume of disperser solvent and extractant solvent and chelating agent concentration) on extraction efficiency. Under the optimized conditions, the analytical curve is linear in a concentration range of 10–750 μgL −1 with a detection limit of 5 μgL −1 . The relative standard deviation (RSD) for ten repeated determinations of iron concentrations at 40 and 200 μgL −1 was calculated to be 4.2% and 1.2%, respectively. Relative recovery of iron in several water samples was investigated and the average was obtained in the range of 91–108%. [ABSTRACT FROM AUTHOR]

Acidified water extraction of total anthocyanin content, total phenol content and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity from black soybeans ( Glycine max [L.] Merr. Cheongja4ho) was optimized using response surface methodology (RSM). A five-level, three-factor central composite design was employed to optimize the conditions for the maximum yields of these three components using19 different experiments. The HCl concentration (0.3–0.5%), solid-liquid ratio (1/30–1/50 g/mL) and extraction temperature (30–50 °C) significantly affected three components. The optimized conditions were HCl concentration of 0.359%, solid-liquid ratio of 1/54.2 g/mL and extraction temperature of 56.8 °C for total anthocyanin content (136.68 mg/100 g), total phenol content (1197.09 mg/100 g) and ABTS + scavenging activity (211.65 mg/100 g). These experimental values fit well with the predicted values. Among three anthocyanins found in the black soybean extracts, cyanidin-3- O -glucoside was the major one (65–73% of the total), followed by petunidin-3- O -glucoside (17–23%) and delphinidin-3- O -glucoside (10–12%). [ABSTRACT FROM AUTHOR]

Effects of extraction time and solvent polarity on antioxidant properties of Brassica oleracea leaves were optimized by response surface methodology using a central composite design. Five extraction times (12, 24, 36, 48 and 60 h) and solvent polarities (dipole moment – hexane: 0.0, diethyl ether: 2.80, ethyl acetate: 4.40, methanol: 5.10 and water: 9.0 D) were selected for optimization. Response surface analysis of data showed a significant increase (p < 0.05) in extract yield and antioxidant potential, based on total phenolic acids, reducing abilities and free radical scavenging capacities, in response to an increase in extraction time and solvent polarity. The optimal response was obtained using relatively polar solvents (4.40–9.00 D) and prolonged extraction times (50–60 h). This suggests that most of the phytochemical constituents of B. oleracea leaves are polar and possess strong antioxidant potential. [ABSTRACT FROM AUTHOR]

Berberis jaeschkeana fruits, source of nutraceutically important polyphenolics were investigated. A total of 32 experimental run were conducted under Plackett-Burman and central composite design. Microwave power, methanol and HCl concentration significantly (p < 0.05) affect extraction of polyphenols under linear, quadratic and interactive effect. The model showed good fitness with significant (p < 0.05) model F-value and a non-significant lack of fit. Under optimum microwave assisted extraction (MAE) condition the total phenolics, flavonoids, tannins and antioxidant activity were in closed context with predicted values. As compared to ultrasonic (UAE) and maceration extraction (ME), MAE showed significantly (p < 0.05) higher recovery of TP, TF and FRAP antioxidant activity. HPLC-DAD analysis detects a total of 10 polyphenolic compounds under MAE as compared to 9 under UAE and ME. Designing of MAE conditions showed promising results for polyphenolic antioxidants extraction as revealed by higher yield with lesser time and solvent consumption, which can contribute in green extraction technology and its application in nutraceutical industry. [ABSTRACT FROM AUTHOR]

This article developed a method to detect two antioxidants (butylated hydroxyl anisole (BHA), butylated hydroxyl toluene (BHT)) and twelve pesticides (dichlorvos, pirimicarb, prothiofos, fenitrothion, ethoprophos, malathion, beta-Cypermethrin, profenofos, diazinon, propoxur, procymidon, captan) in blended oil samples after their extraction simultaneously. The establishment of the method was based on two-step process of screening and optimization experiment design. With a Plackett-Burman (PB) design, significant parameters were found by screening experiment and single factor experiment accompanied by a central composite design (CCD) experiment were used to make important parameters optimal. The coefficients of determination (r 2 ) was between 0.9931 and 0.9996 while the limits of quantification (LOQs) and limits of detection (LODs) were found in scope of 0.002–0.04 mg·kg −1 and 0.0006–0.0012 mg·kg −1 . Recovery values of analytes were above 74%, at the same time the relative standard deviations (RSDs) under 10% at the concentrations ranging from 0.05 mg·kg −1 to 0.20 mg·kg −1 . To sum up, this method with shorter time and fewer consumption of reagents could be employed in various occasions to detect antioxidants and pesticides. [ABSTRACT FROM AUTHOR]

The glycolipid biosurfactants mannosylerythritol lipids (MELs) attract great attention for their biodegradability, super emulsifying properties and versatile bioactivities. In this study, the MEL deriving from Ceriporia lacerate CHZJU was identified as MEL-A, and its critical micelle concentration and emulsifying activities were assessed. To examine the production of MELs from Ceriporia lacerate , a Plackett-Burman design and response surface methodology were used to optimize the culture nutrients. The optimal medium contains 1 g/L yeast extract, 1.5 g/L (NH 4 ) 2 SO 4 , 0.5 g/L KH 2 PO 4 , 0.04 g/L CaCl 2 , 119.6 mL/L soybean oil and 0.297 g/L MnSO 4 . Subsequent verification revealed that the yield of MELs was 129.64 ± 5.67 g/L. Furthermore, an unstructured kinetic model was developed for mycelial growth, MEL production and substrate utilization. This work provides insight into Ceriporia lacerate CHZJU, a predominant fungus producing MEL-A. Optimization using response surface methodology enhanced the mannosylerythritol lipid recovery. Importantly, we developed fermentation kinetic modelling for mannosylerythritol lipid production. [ABSTRACT FROM AUTHOR]

[Display omitted] • New MWCNT based magnetic IIP synthesized for SPE coupled FAAS method development. • Serves twin objective of determination and removal in food, water, wastewater. • Analytical method validation; SRM, recovery, accuracy, precision, robustness. • Cd(II) loaded IIP was exploited for removal of toxic anionic dyes. A 3D Fe 3 O 4 @MWCNT-CdIIP was synthesized by the oxidizing surface of multi-walled carbon nanotubes with carboxylic acid end groups and its subsequent termination with an ion imprinted polymer. An artificial neural network manifests better predictability than the central composite design methodology for optimising the adsorption procedure. The adsorption capacity was 109 mg g−1 (2.5 times more than non-imprinted polymer) under optimized conditions (pH; 5.6, time; 15 min, concentration; 800 μg mL−1 temperature; 25 °C), which was in accord with Toth isotherm. Fractal-like pseudo-second-order kinetics was found reasonably fast, with 66 % adsorption in 5 min. Solid phase extraction coupled Flame atomic absorption spectrometry method provides selective recognition towards Cd(II), with limit of detection; 1.13 µg/L, limit of quantification; 3.21 µg/L after preconcentration (preconcentration factor; 50) and good robustness. The developed method was applied for Cd(II) determination in food (tea, coffee, bread, tobacco, radish, spinach), water and wastewater (>99 % removal as well). Cd(II) loaded IIP was further utilized to remove anionic dyes with >95 % removal. [ABSTRACT FROM AUTHOR]

In traditional ionic liquids (ILs)-based microextraction, ILs are often used as extraction and dispersive solvents; however, their functional effects are not fully utilized. Herein, we developed a novel ionic liquid 1-butyl-3-methylimidazolium naphthoic acid salt ([C 4 MIM][NPA]) with strong acidity. It was used as a mixed dispersive solvent with conventional [C 2 MIM][BF 4 ] in “functionalized ionic liquid-based non-organic solvent microextraction (FIL-NOSM)” for determination of tetracycline antibiotics (TCs) in milk and eggs. Utilization of [C 4 MIM][NPA] in FIL-NOSM method increased extraction recoveries (ERs) of TCs by more than 20% and eliminated the pH adjustment step because of its strong acidity. Under optimized conditions based on central composite design, the ERs of four TCs were 94.1–102.1%, and the limits of detection were 0.08–1.12 μg kg −1 in milk and egg samples. This proposed method provides high extraction efficiency, less pretreatment time and requires non-organic solvents for determination of trace TC concentrations in complex animal-based food matrices. [ABSTRACT FROM AUTHOR]

This work aimed to obtain a simplified extraction protocol for simultaneous achievement of total anthocyanin and total phenolic in açaí pulp using a 3-step optimization approach. First, a Plackett–Burman 20 was applied in 16 independent variables selected in literature. Secondly, seven factors pre-selected in the first screening were reassessed using a Plackett–Burman 12. Then, four selected factors; solid/solvent ratio (g:mL), acetone concentration (%), time of extraction in acidified ethanolic solution (min) and ethanol concentration (%) were optimized using a central composite design with response surface methodology. In addition, the optimized protocol were compared with two standardized extraction procedures assessing açaí and grape pulps. The optimized method is effective for the simultaneous extraction of total phenolics and total anthocyanins, allowing representative measurements of free radical-scavenging capacity (DPPH) and trolox equivalent capacity (TEAC) of grape and açaí pulps, with savings of time and reagents, moreover, avoiding the use of methanol. [ABSTRACT FROM AUTHOR]

Statistical experimental designs were employed to optimize the extraction condition of arsenic species (As(III), As(V), monomethylarsonic acid (MMA) and dimethylarsonic acid (DMA)) in paddy rice by a simple solvent extraction using water as an extraction reagent. The effect of variables were estimated by a two-level Plackett–Burman factorial design. A five-level central composite design was subsequently employed to optimize the significant factors. The desirability parameters of the significant factors were confirmed to 60 min of shaking time and 85 °C of extraction temperature by compromising the experimental period and extraction efficiency. The analytical performances, such as linearity, method detection limits, relative standard deviation and recovery were examined, and these data exhibited broad linear range, high sensitivity and good precision. The proposed method was applied for real rice samples. The species of As(III), As(V) and DMA were detected in all the rice samples mostly in the order As(III) > As(V) > DMA. [ABSTRACT FROM AUTHOR]

In the present work, a new extraction method for separation of nickel from edible oils and determination by FAAS is reported. This method is based on extraction of Ni(II) ions from the oil to aqueous phase with N,N′-bis(4-methoxysalicylidene) ethylenediamine (MSE) and determination by FAAS. Properties of the complex formed between MSE and Ni(II) were investigated spectrophotometrically. Central composite design (CCD) was utilized for optimization of MSE to oil, stirring time and temperature, which were 0.97 mL g −1 , 15.4 min, and 29.7 °C, respectively. The developed method was tested with an oil-based metal standard and the recovery was 93.8 ± 3.9%. The proposed method was applied with five different edible oils. [ABSTRACT FROM AUTHOR]

In this study, different extraction procedures based on the QuEChERS method were compared for the multiresidue determination of pesticides in orange juice by ultra high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC–MS/MS). After choosing preliminary conditions, an experimental design was carried out with the variables C18, PSA, NaOH and CH 3 COONa to optimize the sample preparation step. The validation results of the validation were satisfactory, since the method presented recoveries between 70% and 118%, with RSD lower than 19% for spike levels between 10 and 100 μg L −1 . The method limit of detection (LOD) and limit of quantification (LOQ) ranged from 3.0 to 7.6 μg L −1 and from 4.9 to 26 μg L −1 , respectively. The method developed was adequate for the determination of 74 pesticide residues in orange juice. [ABSTRACT FROM AUTHOR]

Supercritical carbon dioxide (SC-CO 2 ) extraction of sunflower seed for the production of vegetable oil is investigated and compared to conventional methods. The effects of extracting variables, namely pressure, temperatures, particle size, SC-CO 2 flow rate and co-solvent, on SC-CO 2 extraction are investigated. The maximum yield for sunflower oil is found to be about 54.37 wt%, and is obtained when SC-CO 2 extraction is carried out at 80 °C, 400 bar, 0.75 mm particle and 10 g/min solvent flow with 5% co-solvent. A central composite design is used to develop the model and also to predict the optimum conditions. At optimum conditions obtained based on desirability function, 80.54 °C, 345 bar, 1.00 mm, 10.50 g/min and 7.58% ethanol, SC-CO 2 extraction has performed and found that extraction yield dropped by 2.88% from the predicted value. Fatty acid composition of SC-CO 2 and hexane extracted oil shows negligible difference and found high source of linoleic acid. [ABSTRACT FROM AUTHOR]

The present study reports on the extraction of antioxidant compounds from Iranian Ocimum basilicum . Central composite design (CCD) was used to investigate the effect of extraction variables on the ultrasound-assisted extraction (UAE). Three independent variables including temperature, methanol to water ratio percent, and sonication time were studied for simultaneous optimization of antioxidant capacity, total phenolic content and extraction yield. Both quantitative modeling and response surface methodology suggested that methanol to water ratio percent and extraction temperature were the most effective parameters of UAE process. However, sonication time was found out to be an insignificant factor in ultrasound-assisted extraction of antioxidant and total phenolic compounds of O. basilicum . The optimum conditions were determined as temperature of 59 °C, methanol to water ratio of 65.2% (v/v), and extraction time of 20 min. [ABSTRACT FROM AUTHOR]

An HS-SPME method was developed using multivariate experimental designs, which was conducted in two stages. The significance of each factor was estimated using the Plackett–Burman (P–B) design, for the identification of significant factors, followed by the optimization of the significant factors using central composite design (CCD). The multivariate experiment involved the use of Minitab® statistical software for the generation of a 2 7–4 P–B design and CCD matrices. The method performance evaluated with internal standard calibration method produced good analytical figures of merit with linearity ranging from 1 to 500 μg/kg with correlation coefficient greater than 0.99, LOD and LOQ were found between 0.35 and 8.33 μg/kg and 1.15 and 27.76 μg/kg respectively. The average recovery was between 73% and 118% with relative standard deviation (RSD = 1.5–14%) for all the investigated pesticides. The multivariate method helps to reduce optimization time and improve analytical throughput. [ABSTRACT FROM AUTHOR]

Herein, we developed a novel integrated apparatus to perform phase separation based on magnetic-stirring, salt-induced, liquid–liquid microextraction for determination of five fluoroquinolones in animal-based foods by HPLC analysis. The novel integrated apparatus consisted of three simple HDPE (high density polyethylene) parts that were used to separate the solvent from the aqueous solution prior to retrieving the extractant. The extraction parameters were optimized using the response surface method based on central composite design: 791 μL of acetone solvent, 2.5 g of Na 2 SO 4 , pH 1.7, 3.0 min of stir time, and 5.5 min centrifugation. The limits of detection were 0.07–0.53 μg kg −1 and recoveries were 91.6–105.0% for the five fluoroquinolones from milk, eggs and honey. This method is easily constructed from inexpensive materials, extraction efficiency is high, and the approach is compatible with HPLC analysis. Thus, it has excellent prospects for sample pre-treatment and analysis of fluoroquinolones in animal-based foods. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient ASE procedure was developed for lipid profile of mozzarella. • LipidSearch™ software was successfully used for lipid identification in mozzarella. • Response surface methodology was employed to define the best ASE conditions. • The extraction efficiency was principally linked to the MTBE/Cyclohexane ratio. • The contribution of ASE and Folch methods for exhaustive lipid profile was assessed. In this study, a novel Accelerated Solvent Extraction (ASE) procedure combined with UHPLC-Q-Orbitrap-MS was developed for detailed untargeted lipid profile of mozzarella cheese. Response Surface Methodology and Pareto front, using a Central Composite Design (CCD), were employed to define the optimised combination of extraction temperature, number of extraction cycles and mix of solvents. LipidSearch™ software was used for a reliable and accurate lipid identification. A total of 13 subclasses, including ceramides, diacylglycerols, triacylglycerols, lysophosphatidylcholines, lysophosphatidylethanolamines, phosphatidylcholines, phosphatidylethanolamines, phosphatidylinositols, sphingomyelins, bismethyl phosphatidic acids, cholesterol ester, zymosterol ester, hexosyl ceramides were measured. The elaboration of the CCD showed that the solvents ratio was the main factor affecting the extraction efficiency. The optimised ASE method, together with the Folch extraction, synergistically contributed to a complete characterization of lipid profile of mozzarella cheese, confirming ASE technique, associated with high resolution mass spectrometry detection, as an efficient tool for Lipidomics in food science. [ABSTRACT FROM AUTHOR]

• One-step derivatization and TC-VA-LLME-SFDES method was developed. • Hydrophobic DESs were used as both reducing agent and extraction solvent. • Only 2 min was needed for derivatization and extraction process. • The method was applied for analysis of total Fe in water and food samples. • The method opened up the application of solid DESs in LLME technique. In our work, hydrophobic thymol-based deep eutectic solvents (DESs) with strong reducibility, a lower density than water, and a slightly higher melting point than room temperature were synthesized. Based on these solid DESs, one-step derivatization and temperature-controlled vortex-assisted liquid-liquid microextraction based on the solidification of a floating DES (TC-VA-LLME-SFDES) via UV–Vis spectrophotometry for the rapid determination of total iron was developed. The derivatization and TC-VA-LLME were carried out simultaneously by the addition of DES as both the reducing agent and extraction solvent. After optimization, the calibration curve (5–250 μg L−1, R2 = 0.9982), limit of detection (1.5 μg L−1), limit of quantitation (5.0 μg L−1), precision (≤4.0%) and enrichment factor (92) was obtained. This method was applied for the determination of total iron in water and food samples with satisfactory recoveries (85.4–106.2%). One-step derivatization and TC-VA-LLME only required 2 min. Furthermore, this method opened up the application of solid DESs in liquid–liquid microextraction. [ABSTRACT FROM AUTHOR]

Highlights: [•] UAE–DLLME coupled with GC–MS was developed for determination of saffron components. [•] The components were extracted by ultrasound, and preconcentrated via DLLME method. [•] A half-fraction CCD was used for optimisation and data modelling of the extraction. [•] The method was performed at room temperature and darkness for sensitive compounds. [•] The method is fast, simple, low cost and consuming low plant and organic solvent. [ABSTRACT FROM AUTHOR]

Abstract: Response surface methodology (RSM) based on a central composite design (CCD) was applied to optimise the extraction conditions for flavonoids from fructus sophorae with advantages in terms of resisting flavonoids during the whole process and maximising of extraction yield. Three aglycon forms of the flavonoids, namely, quercetin, kaempferol and isorhamnetin were quantified by high-performance liquid chromatography with ultraviolet detection (HPLC-UV) to estimate extraction yield. The combined effects of independent variables were studied and the optimal extraction conditions were obtained as ethanol concentration, 74.47%; solid–liquid ratio, 17.99ml/g; temperature, 89.13°C; and extraction time, 2.10h. The reliability of the method was confirmed by recovery experiments, performed under optimal conditions. Recoveries indicated that flavonoids resisted the extraction conditions. The experimental extraction yield under optimal conditions was found to be 10.459%, which was well matched with the predicted values of 10.461%. [Copyright &y& Elsevier]

Abstract: Bioaccessibility studies should be taken into account when evaluating the physiological effects of ingested compounds at the intestine level. Several in vitro digestion protocols have been described, with a wide range of experimental conditions but no optimised protocol exists. In order to fill in this gap, we evaluated the influence of three continuous factors (pH, incubation time, and enzyme concentrations), in the range of values found in literature, on the digestion of standard macronutrients (starch, albumin, triolein) alone or in mixture. Three central composite designs, using response surface methodology, were employed to model the three abiotic steps of pre-colonic digestion. A validated in vitro digestion was eventually set up for the salivary step (pH 6.9, 5min, 3.9units α-amylase/ml), the gastric step (pH 2, 90min, 71.2units pepsin/ml), and the abiotic duodenal step (pH 7, 150min, 9.2mg pancreatin and 55.2mg bile extract/ml). [Copyright &y& Elsevier]

Abstract: The objective of this work was to optimise different parameters (solvent concentration, time and temperature) for antioxidant extraction from kinema, demonstrated by total phenol content (TPC) and DPPH -scavenging activity (DSA), using response surface methodology. A central composite design was performed to determine the effect of solvent concentration (methanol, 30–100%), temperature (30–60°C) and time (30–150min) on the TPC and DSA of the extract. The solvent concentration and temperature had the most significant (p <0.05) effect. The optimum conditions for the TPC extraction and DSA were 100% methanol, 50°C and 30min, in which 140mg of gallic acid equivalent (GAE) g−1 lyophilised extract and 52% DSA were predicted, while 135mg GAE g−1 lyophilised extract and 56% DSA were experimentally obtained. No significant difference (p <0.05) was found between the experimental and predicted values of the response variables. [Copyright &y& Elsevier]

Abstract: Three low-fatty baby food matrices were fortified with 0.01–0.2mg/kg of phorate, diazinon, chlorpyrifos and methidathion. A “quick, easy, cheap, effective, rugged and safe” – like method (QuEChERS) was used. Quantities of octadecyl (C18) sorbent differed with fortification level and matrix fat, based on central composite experimental design. Quantification was performed by Nitrogen–Phosphorus Detector gas chromatography, using matrix-matched standards. The highest (p <0.05) recoveries were observed for methidathion, the lowest fortification levels for a specific C18 amount and the lowest C18 amounts. In meals containing vegetables (1.9% fat) and lamb (3.0% fat), 180–210mg C18 gave recoveries from 67.0% to 105.0% and absence of co-extracts. Yogurt dessert (4.5% fat) required 200–230mg C18 for similar results. Recoveries could also be predicted with <20% error by a polynomial model. The results suggest that modified QuEChERS could be effectively used in the low-fatty baby meals residue analysis. [Copyright &y& Elsevier]