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The aim of this work was comparison study of dilution and plating method for evaluation of the synergism effect of metal-organic framework nanocubes (MOF-5-NCs) and broccoli extract ( Brassica oleracea ) on antibacterial activity of standard and clinical Pseudomonas aeruginosa strains. For this purpose, sonochemical synthesis of MOF-5-NCs was performed and it was characterized using XRD, FT-IR, FESEM and EDS techniques. Maceration extraction (ME) and ultrasound assisted extraction (UAE) methods in three different solvents were prepared and applicability of their extracts were compared in some cases such as radical scavenging and antioxidant activity. The HPLC/UV analysis was applied for separation, identification and evaluation of phenolic acids in prepared broccoli extracts. Then, antimicrobial activity of MOF-5NCs and broccoli extract against gram-negative bacteria, Pseudomonas aeruginosa was evaluated by detection of minimal inhibition concentration (MIC), minimal bactericidal concentration (MBC) and zone of inhibition (ZOI). The results of in vitro assays showed that dilution method due to flase estimation of 4% viability percentage which is not logic by consideration of MBC well could not be able to estimate MBC. Therefore, plate count method was performed for precise calculation of MBC. MIC of broccoli extract and MOF-5-NCs on Pseudomonas aeruginosa strains were 7.81 mg mL −1 and 3.13 mg mL −1 , respectively. [ABSTRACT FROM AUTHOR]

(1) Background: Ionic liquids (ILs) are considered "green" solvents and have been widely used in the extraction and separation field in recent years; (2) Methods: In this study, some common ILs and functionalized magnetic ionic liquids (MILs) were used as adjuvants for the solvent extraction of paclitaxel from Taxus x media (T. x media) using methanol solution. The extraction conditions of methanol concentration, IL type and amount, solid--liquid ratio, extraction temperature, and ultrasonic irradiation time were investigated in single factor experiments. Then, three factors of IL amount, solid--liquid ratio, and ultrasonic irradiation time were optimized by response surface methodology (RSM); (3) Results: The MIL [C4MIM]FeCl3Br was screened as the optimal adjuvant. Under the optimization conditions of 1.2% IL amount, 1:10.5 solid--liquid ratio, and 30 min ultrasonic irradiation time, the extraction yield reached 0.224 mg/g; and (4) Conclusions: Compared with the conventional solvent extraction, this ultrasonic assisted extraction (UAE) using methanol and MIL as adjuvants can significantly improve the extraction yield, reduce the use of methanol, and shorten the extraction time, which has the potentiality of being used in the extraction of some other important bioactive compounds from natural plant resources [ABSTRACT FROM AUTHOR]

Substantial amount of apple pomace (AP) is produced in apple processing industries and is often discarded as waste which becomes a source of polluting the environment. However, the by-product constitutes a promising bioresource of ursolic acid with various biological activities. Therefore, this particular research study was aimed to develop a novel and facile method to separate ursolic acid from AP. First, AP was extracted with ultrasound assistance using methanol as extraction solvent, 2.86% with 10:1 (mL g−1) of liquid–solid ratio, 300 W of ultrasonic power, 50°C of extraction temperature, and 90 min of ultrasonic time. Meanwhile, the disruption effect of ultrasound on AP was observed by scanning electron microscope. Second, a novel and facile method was applied to separation of ursolic acid, then a perfect colorless needle crystal of ursolic acid was obtained with the yield of about 1.34% of dry AP. [ABSTRACT FROM AUTHOR]

The ultrasonic assisted temperature-switch ionic liquid microextraction (UATS-ILME) has been successfully applied in extracting of seven lignans from Schisandra . 1-Butyl-3-methylimidazolium tetrafluoroborate ([C 4 MIM][BF 4 ]) aqueous solution was selected for extracting the target analytes in raw material at 80 °C. The lignans were deposited into a single drop by in situ forming 1-butyl-3-methylimidazolium hexafluorophosphate ([C 4 MIM][PF 6 ]) by cooling down to 0 °C and centrifuging for 10 min. The extracts were analyzed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) in a robust multiple-reaction monitoring (MRM) mode in five minutes. Meanwhile, the proposed method was validated and successfully applied to the determination of seven lignans in twelve Schisandra species. The results indicated that UATS-ILME combined with UPLC-MS/MS is a powerful and practical tool, which has great potential for comprehensive quality control of herbal medicines. [ABSTRACT FROM AUTHOR]

In this paper, response surface methodology was employed to optimize experimental process for ionic liquid based ultrasonic assisted extraction of curcuminoids compounds from rhizomes of Curcuma longa L. The Box–Behnken design on three factors and five levels together with response surface methodology were used to optimize experimental conditions for total curcuminoids content and radical scavenging capacity. The radical scavenging capacity was determined by ABTS and TRAP methods. For the ionic liquid based ultrasonic assisted extraction, optimum process was set as below: [Omim]Br concentration, 4.2 mol/L; liquid-raw ratio, 30 mL/g; extraction time, 90 min; ultrasonic power, 250 W. [ABSTRACT FROM AUTHOR]

Highlights: [•] Soybean curd residue was reused by G. lucidum to produce polysaccharide. [•] Polysaccharides yield was improved by optimal ultrasonic treatment conditions. [•] Polysaccharides showed strong antioxidative effects by seven antioxidant assays. [•] Polysaccharides exhibited strong immunomodulation activities. [Copyright &y& Elsevier]

A simple, highly sensitive and environment-friendly method, combined with flame atomic absorption spectroscopy (FAAS) is developed to preconcentrate and determine trace amounts of thallium in aqueous solutions. In the preconcentration step, the thallium (I) from 30 mL of an aqueous solution was extracted into 350 µL of ionic liquid, 1-hexyl-3-methylimidazolium hexafluorophosphate [Hmim][PF6], containing dicyclohexyl-18-crown-6 (DCH-18-crown-6) as complexing agent. Subsequently, the DCH-18-crown-6 complex was back-extracted into 300 µL of nitric acid (2 mol L−1) solution, and analyzed by FAAS. Several parameters influencing the extraction and determination of thallium, such as pH, concentration of DCH-18-crown-6, sonication and centrifugation times, sample volume, ionic liquid amounts, ionic strength, and concentration of stripping acid solution, were optimized. Under optimum conditions, the calibration graph was linear in the range of 5 to 400 ng mL−1, the detection limit was 0.64 ng mL−1(3Sb/m,n = 7), the enhancement factor was 98.2 and the relative standard deviation was ±1.43%. The results for preconcentration and determination of trace amount of thallium in waste water, well water, tap water, sea water, human hair and nail demonstrated the accuracy, recovery and applicability of the presented method. [ABSTRACT FROM PUBLISHER]

Abstract: In this work, ultrasonic assisted extraction combined with solid phase extraction (SPE) was applied in the analysis of polycyclic aromatic hydrocarbons (PAHs) in environment samples. A titania nanotubes/titanium plate was modified with n-octadecanethiol monolayer-protected Ag nanoparticles, and developed as the adsorbent in SPE of PAHs. Six different PAHs in soil samples were analyzed with high performance liquid chromatography-fluorescence detection. The experiment conditions including the deposition time of Ag nanoparticles, extraction solvent properties, the amount of extraction solvent, the amount of organic modifier, extraction time, and desorption solvent properties were optimized. Under the optimized conditions, good linearity and low limits of detection of 0.0015–0.4ngg−1 were obtained. The analysis of PAHs in real soil samples gave satisfactory recoveries ranging from 70.32% to 115.51% with 3.14%–13.56% intra-day relative standard deviations (RSD) and 4.92%–14.87% inter-day RSD. [Copyright &y& Elsevier]

Abstract: This work describes optimization of headspace single drop micro-extraction for extraction of five organophosphorus pesticides; thionazin, sulfotep, dimethoate, disulfoton and parathion in soil. Ultrasound has also been used successfully to improve and accelerate the extraction of the analytes from the sample. The optimized extraction performance was obtained when the experimental parameters were set as follows; 3.0μL of octanol as extraction solvent, high ionic strength (20% sodium chloride), 1:1 (w/v) sample dilution with water, extraction temperature at 60°C for 30min; applying ultrasound and without any pH adjustment. The optimized method was linear over the calibration range (5–200 and 10–300 for different analytes) with limits of detection of 0.1–2.0ngg−1. The enrichment factor for OPPs was 1.4–12.7 and the method was also reproducible with the relative standard deviations (RSD%) of 2.1–6.9%. [Copyright &y& Elsevier]

Abstract: We developed an aqueous ionic liquid based ultrasonic assisted extraction (ILUAE) method for the extraction of the eight ginsenosides (ginsenoside-Rg1, -Re, -Rf, -Rb1, -Rc, -Rb2, -Rb3 and -Rd) from ginseng root. A series of l-alkyl-3-methylimidazolium ionic liquids differing in composition of anions and cations were evaluated for extraction efficiency. The results indicated that the ILUAE method has a remarkable ability to improve the extraction efficiency of ginsenosides. In addition, the ILUAE procedure was also optimized on some ultrasonic parameters, such as the IL concentration, solvent to solid ratio and extraction time. Under these optimal conditions (e.g., with 0.3M [C3MIM]Br, solvent to solid ratio of 10:1 and extraction time of 20min), this approach gained the highest extraction yields of total ginsenosides 17.81±0.47mg/g. Compared with the regular UAE, the proposed approach exhibited 3.16 times higher efficiency and 33% shorter extraction time, which indicated that ILUAE has a broad prospect for sample preparation of medicinal plants. [Copyright &y& Elsevier]

Response surface methodology (RSM) using a central composite design (CCD) was employed to optimize the conditions for extraction of antioxidants from black soybean (Glycine max var) sprouts. Three influencing factors: liquid-solid ratio, period of ultrasonic assisted extraction and extraction temperature were investigated in the ultrasonic aqueous extraction. Then Response Surface Methodology (RSM) was applied to optimize the extraction process focused on DPPH radical-scavenging capacity of the antioxidants with respect to the above influencing factors. The best combination of each significant factor was determined by RSM design and optimum pretreatment conditions for maximum radical-scavenging capacity were established to be liquid-solid ratio of 29.19:1, extraction time of 32.13 min, and extraction temperature of 30 °C. Under these conditions, 67.60% of DPPH radical-scavenging capacity was observed experimentally, similar to the theoretical prediction of 66.36%. [ABSTRACT FROM AUTHOR]

Abstract: In this study, an aqueous ionic liquid based ultrasonic assisted extraction (ILUAE) method for the extraction of the four acetophenones, namely 4-hydroxyacetophenone (1), 2,5-dihydroxyacetophenone (2), baishouwubenzophenone (3) and 2,4-dihydroxyacetophenone (4) from the Chinese medicinal plant Cynanchum bungei was developed. Three kinds of aqueous l-alkyl-3-methylimidazolium ionic liquids with different anion and alkyl chain were investigated. The results indicated that ionic liquids (ILs) showed remarkable effects on the extraction efficiency of acetophenones. In addition, the ILUAE, including several ultrasonic parameters, such as the ILs concentration, solvent to solid ratio, power, particle size, temperature, and extraction time have been optimized. Under these optimal conditions (e.g., with 0.6M [C4MIM]BF4, solvent to solid ratio of 35:1, power of 175W, particle size of 60–80 mesh, temperature of 25°C and time of 50min), this approach gained the highest extraction yields of four acetophenones 286.15, 21.65, 632.58 and 205.38μg/g, respectively. The proposed approach has been evaluated by comparison with the conventional heat-reflux extraction (HRE) and regular UAE. The results indicated that ILUAE is an alternative method for extracting acetophenones from C. bungei. [Copyright &y& Elsevier]

Abstract: Ionic liquid (IL) based ultrasonic assisted extraction (ILUAE) was developed for the effective extraction of puerarin from Radix Puerariae Lobatae (RPL). The ILUAE parameters including the type of ILs, IL concentration, RPL amount, ultrasonic power and time were optimized by single-factor experiment and response surface methodology. Under the optimized experimental conditions, the best results were obtained using RPL amount 0.43g in 10mL 1.06molL−1 1-butyl-3-methylimidazolium bromide aqueous solution, ultrasonic time 27.43min and ultrasonic power 480W. Scanning electron microscope images of RPL samples were obtained to provide visual evidence of the sonication effect. Compared with the conventional ultrasonic assisted extraction and refluent extraction, the proposed ILUAE offered shorter extraction time and remarkable higher efficiencies due to the higher penetration ability and solubility of IL and the cavitation phenomenon produced in the solvent by the passage of an ultrasonic wave, which further supported the suitability of the proposed approach. [Copyright &y& Elsevier]

A method for the analysis of chlorotoluenes (CTs) in soil has been developed based on ultrasonic assisted extraction with a low volume of organic solvent and determination by gas chromatography-tandem mass spectrometry (GC–MS/MS). A simultaneous clean-up on an alumina–anhydrous sodium sulphate mixture was carried out to remove soil interferences. However, an additional clean-up with graphitised carbon was needed for some very dirty samples. Several solvents were assayed and a mixture of ethyl acetate:hexane (80 : 20, v/v) was selected to carry out soil extractions. Recovery studies were performed at 0.2, 0.1, 0.05 and 0.02 ng g−1 fortification levels, and recoveries obtained for all the compounds and concentrations were higher than 81% with standard deviations fulfilling the requirements of the IUPAC. LODs from 0.7 to 5.2 ng kg−1 and LOQs from 2.2 to 17.5 ng kg−1 were achieved for the analysed compounds, being pentachlorotoluene the compound with the highest limits, followed by the monochlorinated toluenes. The proposed analytical method was applied to determine CT levels in agricultural and industrial soils. These compounds were found in all the industrial soils analysed and some CTs were present in agricultural soils at lower levels. [ABSTRACT FROM AUTHOR]

Abstract: Lycopene extraction was carried out via the ultrasonic assisted extraction (UAE) with response surface methodology (RSM). Sonication enhanced the efficiency of relative lycopene yield (enhancement of 26% extraction yield of lycopene in 6 replications at 40.0min, 40.0°C and 70.0% v/w in the presence of ultrasound), lowered the extraction temperature and shortened the total extraction time. The extraction was applied with the addition of oxygen-free nitrogen flow and change of water route during water bath sonication. The highest relative yield of lycopene obtained was 100% at 45.0°C with total extraction time of 50.0min (30:10:10) and ratio of solvent to freeze-dried tomato sample (v/w) of 80.0:1. Optimisation of the lycopene extraction had been performed, giving the average relative lycopene yield of 99% at 45.6min, 47.6°C and ratio of solvent to freeze-dried tomato sample (v/w) of 74.4:1. From the optimised model, the average yield of all-trans lycopene obtained was 5.11±0.27mg/g dry weight. The all-trans lycopene obtained from the high-performance liquid chromatography (HPLC) chromatograms was 96.81±0.81% with 3.19±0.81% of cis-lycopenes. The purity of total-lycopene obtained was 98.27±0.52% with β-carotene constituted 1.73±0.52% of the extract. The current improved, UAE of lycopene from tomatoes with the aid of RSM also enhanced the extraction yield of trans-lycopene by 75.93% compared to optimised conventional method of extraction. Hence, the current, improved UAE of lycopene promotes the extraction yield of lycopene and at the same time, minimises the degradation and isomerisation of lycopene. [Copyright &y& Elsevier]

Abstract: In this article, we consider ionic liquid based ultrasound-assisted dispersive liquid–liquid microextraction of trace amounts of rhodium from aqueous samples and show that this is a fast and reliable sample pre-treatment for the determination of rhodium ions by flame atomic absorption spectrometry. The Rh(III) was transferred into its complex with 2-(5-bromo-2-pyridylazo)-5-diethylamino phenol as a chelating agent, and an ultrasonic bath with the ionic liquid, 1-octyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide at room temperature was used to extract the analyte. The centrifuged rhodium complex was then enriched in the form of ionic liquid droplets and prior to its analysis by flame atomic absorption spectrometry, 300μL ethanol was added to the ionic liquid-rich phase. Finally, the influence of various parameters on the recovery of Rh(III) was optimized. Under optimum conditions, the calibration graph was linear in the range of 4.0–500.0ngmL−1, the detection limit was 0.37ngmL−1 (3S b/m, n =7) and the relative standard deviation was ±1.63% (n =7, C =200ngmL−1). The results show that ionic liquid based ultrasound assisted dispersive liquid–liquid microextraction, combined with flame atomic absorption spectrometry, is a rapid, simple, sensitive and efficient analytical method for the separation and determination of trace amounts of Rh(III) ions with minimum organic solvent consumption. [ABSTRACT FROM AUTHOR]

Abstract: A method has been developed for the analysis of a wide polarity range of the currently used organophosphorus pesticides (OPs) and their metabolites in sewage sludge samples. Extraction was carried out using ultrasonic assisted extraction (UAE) with different solvents. The levels of OPs in sludge were determined by liquid chromatography-tandem mass spectrometry (LC–MS/MS) using electrospray ionization (ESI) in positive or negative ion mode. Extraction with acetonitrile containing 1% acetic acid gave the best results with recoveries between 83.2% and 106.4% and RSD≤8.7%. Evaluation of matrix effect showed high ion suppression for OPs of intermediate polarity, which decreased to approximately 50% by matrix dilution to an equivalent of 0.5g of sludge per millilitre; however, for polar OPs, the matrix effect was negligible at the same concentration. Therefore, matrix-matched standards were used for OPs quantification. The limits of quantification were in the range of 1–14ngg−1. This method was successfully applied to real sludge samples collected from Madrid Province and chlorpyrifos along with its metabolite TCPY were the OPs found in sludge at the highest levels, 113–344ngg−1 and 33–307ngg−1, respectively. [Copyright &y& Elsevier]