Single-step Extraction Method Research Articles

Optimization of single-step gelatin extraction from pink perch (Nemipterus japonicus) skin and bone obtained from surimi industry using a green solvent.

Surimi industry produces a large quantity of byproducts that are currently being utilized to produce low-value commodities. This study aims to extract gelatin from pink perch skin and bone obtained from the surimi industry using a green single-step extraction method. In addition to using a green solvent, that is, acetic acid, the new method combines the multiple steps of pre-treatment and hydrolysis into one single-step extraction process. Response surface methodology was used to optimize extraction parameters (pH, temperature, and time) to maximize yield and l-hydroxyproline (l-hyp) content. The optimum condition for gelatin extraction was obtained at pH 3, 75°C, and 30min. At optimum conditions, gelatin yield and l-hyp content were observed to be 16.07% and 41.26mgg-1 , respectively. The gelatin obtained at optimized condition was further compared with commercial bovine gelatin (BG) in terms of chemical composition and textural, functional, and rheological properties. The results suggested that the optimized pink perch gelatin had higher protein content (92.06%), better gel strength (251.08g), higher imino acid (18.01%), and improved textural and functional properties than the commercially available BG. The optimized single-step gelatin extraction method from pink perch skin and bones is a promising, rapid, and efficient method for the production of good-quality gelatin, which can be further used for the development of high-value products such as food formulations. PRACTICAL APPLICATION: Fish gelatin is widely used in food product development. Most of the existing methods of the development of high-value product such as gelatin, use multi-step process and harsh mineral acid, therefore, are time-consuming and harmful to the environment. This study provides a green single-step gelatin extraction method that provides an efficient, rapid, and convenient method of gelatin extraction and a sustainable solution for fish industry byproduct utilization. The data obtained with this laboratory-scale study provides a strong basis for scale-up studies.

Comparing Efficiency of Green Methods for Surimi Skin and Bone Gelatin Extraction

Globally, the surimi processing industry produces a large amount of by-products in the form of head and viscera, skin, bones, scale, etc. The aim of this study was to assess the combined biomass of pink perch skin and bones obtained from the surimi industry as a potential source of raw material for gelatin production and identify a green method of gelatin extraction by comparing four green processes. Four green gelatin extraction processes were compared for their gelatin extraction efficiency. Among the four processes, process 1 and process 2 comprised of two-step extraction viz pre-treatment with NaCl and extraction with hot water. Process 3 and process 4 comprised of single-step wherein pre-treatment and extraction were done simultaneously with acidic water using acetic acid. The gelatin extraction efficiency was determined based on the yield and L-hydroxyproline content of the extracted gelatin. Further, the extracted gelatin was characterized for their proximate and amino acid composition. The acetic acid based single-step method was found to be more efficient in the extraction of gelatin than the NaCl pretreatment method. The gelatin extracted with this method had a higher yield (4.2%), protein content (79.6%), and imino acid (27.3%) content than the NaCl pretreatment method, which had 1.51% gelatin yield, 48.1% protein content, and 13.1% imino acid content. The results suggested that the single-step extraction method can be effectively utilized for the extraction of gelatin from pink perch skin and bones combined biomass. This study provides a method for the valorization of the surimi industry by-product into a high value product with potential application in various industries.

Hair analysis of selected drug-facilitated sexual assault substances using green supramolecular solvent extraction and LC-MS/MS analysis

Drug-facilitated sexual assault (DFSA) investigations require the consumption history of certain drugs by the victim. Hair; as a keratinized biological sample, offers the possibility to perform retrospective quantitative analysis due to its large window of detection in comparison to other biological matrices. Many analytical methods have been reported to determine class-specific DFSA substances. However, generic methods able to determine multiclass DFSA substances and which are also more sustainable remain pending. In this paper, we develop an efficient and eco-friendly generic single-step extraction method, based on the use of a supramolecular solvent (SUPRAS) made up of 1,2-hexanediol, to extract benzodiazepines, z-hypnotic compounds, cocaine and metabolites, amphetamine derivatives and other miscellaneous compounds involved in DFSA from hair. The proposed method offers a high extraction recovery (>86%) and acceptable matrix effects for 91% of the 23 tested substances, which cover a wide polarity range (log P from − 0.3 to 7.0). The estimated method detection and quantification limits were in the ranges 0.1–24.2 pg/mg and 0.4–80 pg/mg, respectively, and were lower than the recommended drug cut-off levels for all the studied substances, except for 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid. This fast and environmentally friendly method has been successfully applied to quantify DFSA substances in different hair samples.

Development of Hyphenated Techniques and Network Identification Approaches for Biotransformational Evaluation of Promising Antitubercular N-pyrrolyl hydrazide-hydrazone in Isolated Rat Hepatocytes.

Novel, rapid and precise RP-HPLC-DAD method was developed, validated and successfully applied for determination of metabolic changes of ethyl 5-(4-bromophenyl)-1-(3-(2-(2-hydroxybenzylidene)hydrazinyl)-3-oxopropyl)-2-methyl-1H-pyrrole-3-carboxylate (12b) in isolated rat hepatocytes. The analytes were detected by a simple DAD detector at 279nm wavelength. A single-step extraction method was implemented to enable fast purification and extraction from cellular culture, resulting in a complete recovery. Thereafter, the method was adequately transferred to a LC-MS system for identification of unknown products. Additionally, network metabolism evaluation was performed to predict the structures of major metabolites with their isotope mass through BioTransformer 3.0. The data from the LC-MS analysis and the online server were compared for comprehensive identification. The results indicated formation of four metabolic products, obtained through processes of hydrolysis (12 and b), hydroxylation in the structure 12b (M1) and O-dealkylation (M2).

Chemical association and combustion behaviour of cadmium in coal of different mining fields using sequential and single step extraction methods

ABSTRACT This work sought to conduct the chemical association of a toxic metal (cadmium) in coal samples of various origins in Pakistan. For that purpose, a sequential extraction scheme recommended by the Community Bureau of Reference (BCR) has been carried out to know the chemical fractionation of Cd in different coal samples. Simultaneously a time saving vortex-assisted single-step extraction (VA-SSE) via the same experimental parameters conditions used in each fraction steps of BCR sequential extraction procedure (BCR-SE). The coal samples were collected from Thar coal (TCF) and Lakhra coal fields (LCF) of Sindh, Pakistan. The validity of BCR-SE and VA-SSE were checked by applying spiking standard addition procedure on real coal samples. The BCR-SE and VA-SSE were completed in 51 h and 1.0–2.0 min, respectively. In second phase determined the combustion behaviour of Cd or/amount of Cd in coal samples volatilise after heating in an electric furnace in laboratory at three temperature interim (200°C, 400°C and 900°C). The coal ash obtained at 900°C was put to three step sequential extraction method. The evaluated result showed that the total values of Cd in coal samples of block II of Thar coal field (TCF), Site I and Site II of Lakhra coal field (LCF) were found in the range of 3.42–4.43, 2.02–2.82 and 2.91–3.92 mg/kg, correspondingly. The final result indicated that the major chemical fraction of Cd was bound with organic phase of coal samples of both origins (about 40%). The evaluated data showed that 60–71% of Cd in coal samples was found in first three fractions, whilst about 29–40% of Cd was observed in residual. The extracted Cd concentrations in various chemical fractions of coal samples obtained through VA-SSE were 1.6–2.6%, higher than those values gained via BCR-SE (p < 0.04). The resulted data indicated that, after burning of coal samples at 900°C, about 63–69% of total Cd in coal samples of both mining areas was found in residual ash, while 31–34% was vaporised/volatilised out into the atmosphere.

Date palm-magnetized biochar for in-situ stabilization of toxic metals in mining-polluted soil: evaluation using single-step extraction methods and phytoavailability

Mining activities provide a pathway for the entry and accumulation of various heavy metals in soil, which ultimately leads to severe environmental pollution. Utilization of various immobilizing agents could restore such contaminated soils. Therefore, in this study, date palm-derived biochars (BCs: produced at 300 °C, 500 °C and 700 °C) and magnetized biochars (MBCs) were employed to stabilize heavy metals (Cd, Pb, Cu and Zn) in mining polluted soil. Metal polluted soil was amended with BCs and MBCs at w/w ratio of 2% and cultivated with wheat (Triticum aestivum L.) in a greenhouse. After harvesting, dry and fresh biomass of plants were recorded. The soil and plant samples were collected, and the concentrations of heavy metals were measured after extracting with water, DTPA (diethylenetriaminepentaacetic acid), EDTA (ethylenediaminetetraacetic acid), and acetic acid. BCs and MBCs resulted in reduced metal availability and uptake, with higher fresh and dry biomass (>36%). MBCs showed maximum decrease (>70%) in uptake and shoot concentration of metals, as these reductions for Cd and Pb reached below the detection limits. Among all single-step extractions, the DTPA-extractable metals showed a significant positive correlation with shoot concentrations of tested metals. Thus, the synthesized BCs and MBCs could effectively be used for stabilizing heavy metals and improve plant productivity in multi-contaminated soils. However, future studies should focus on long term field trials to restore contaminated mining soils using modified biochars.

Development and validation of an LC-MS/MS method for the quantification of mescaline and major metabolites in human plasma

Mescaline is a psychedelic phenethylamine found in different species of cacti. Currently, mescaline’s acute subjective effects and pharmacokinetics are investigated in several modern clinical studies. Therefore, we developed a bioanalytical method for the rapid quantification of mescaline and its metabolites in human plasma. Mescaline and its metabolites 3,4,5-trimethoxyphenylacetic acid (TMPAA), N-acetyl mescaline (NAM), and 3,5-dimethoxy-4-hydroxyphenethylamine (4-desmethyl mescaline) were simultaneously analyzed by ultra-high performance liquid chromatography tandem mass spectrometry (LC-MS/MS). Optimal chromatographic separation was achieved with an Acquity Premier HSS T3 C18 column. The analytes were detected in positive ionization mode using scheduled multiple reaction monitoring. A single step extraction method was implemented to enable fast and automatable plasma sample preparation. An intra-assay accuracy between 84.9% and 106% and a precision of ≤ 7.33% was observed in three validation runs. Plasma was extracted by simple protein precipitation, resulting in a complete recovery (≥ 98.3%) and minor matrix effects (≤ 7.58%). No interference with endogenous matrix components could be detected in human plasma samples (n = 7). Importantly, method sensitivity sufficed for assessing pharmacokinetic parameters of mescaline in clinical study samples with lower limits of quantification of 12.5, 12.5, and 1.25 ng/mL for mescaline, TMPAA, and NAM, respectively. Nonetheless, 4-desmethyl mescaline could not be selectively quantified in pharmacokinetic samples due to interference with another mescaline metabolite. Overall, we developed and validated a reliable and very easy-to-use method for forensic applications as well as investigating the clinical pharmacokinetics of mescaline.

Microwave-assisted single-step extraction method for determination of heavy metals in saline soil and compare with conventional sequential extraction method

The present research assesses the chemical fractionation of cadmium (Cd), chromium (Cr), and lead (Pb) detected in saline soil samples of Hyderabad Pakistan. Based on the reagents used in the BCR three-step conventional sequential extraction (CSE) for partitioning Cd, Cr, and Pb in saline soil samples, a Microwave induced single-step extraction (MSE) method was developed. The validity of the method was confirmed using certified reference material (CRM) BCR-483 and the standard method of addition (recoveries 96–102%). The data provided by the BCR- CSE method for Cd, Cr and Pb partition were compatible with MSE using the same operating conditions applied and checked in BCR fraction by the Certified Reference Material (CRM) BCR-483. Using compromised sonication and microwave conditions steps 1–3 of the sequential extraction (excluding hydrogen peroxide digestion in step 3) could be accomplished with ultrasonic bath between 15 and 30 min, whereas 60–120 s needed for MSE. The total concentrations of Cd, Cr, and Pb extractable metals produced by three separate extractions ranged 1.02–3.30, 5.02–9.95 and 3.97–8.01 μgg−1, respectively. The accuracy of the proposed BCR single extraction methods (expressed as RSD %) for all metals was found within the range of (4.99–8.61%).

A comprehensive comparison of four methods for extracting lipids from Arabidopsis tissues

BackgroundThe plant lipidome is highly complex, and the composition of lipids in different tissues as well as their specific functions in plant development, growth and stress responses have yet to be fully elucidated. To do this, efficient lipid extraction protocols which deliver target compounds in solution at concentrations adequate for subsequent detection, quantitation and analysis through spectroscopic methods are required. To date, numerous methods are used to extract lipids from plant tissues. However, a comprehensive analysis of the efficiency and reproducibility of these methods to extract multiple lipid classes from diverse tissues of a plant has not been undertaken.ResultsIn this study, we report the comparison of four different lipid extraction procedures in order to determine the most effective lipid extraction protocol to extract lipids from different tissues of the model plant Arabidopsis thaliana.ConclusionWhile particular methods were best suited to extract different lipid classes from diverse Arabidopsis tissues, overall a single-step extraction method with a 24 h extraction period, which uses a mixture of chloroform, isopropanol, methanol and water, was the most efficient, reproducible and the least labor-intensive to extract a broad range of lipids for untargeted lipidomic analysis of Arabidopsis tissues. This method extracted a broad range of lipids from leaves, stems, siliques, roots, seeds, seedlings and flowers of Arabidopsis. In addition, appropriate methods for targeted lipid analysis of specific lipids from particular Arabidopsis tissues were also identified.

Serum Concentrations of Carotenoids and Fat-Soluble Vitamins in Relation to Nutritional Status of Patients with Ovarian Cancer

In this study, we aimed to determine serum concentrations of carotenoids and fat-soluble vitamins (FSVs) in ovarian cancer (OC) patients categorized by clinical and nutritional status and to compare obtained results with healthy controls. We used single-step extraction methods throughout the study. Serum concentrations of the bioactive compounds were measured using HPLC. The evaluation of the nutritional status of patients was performed with scored PG-SGA questionnaire. The serum bioactive compound levels were significantly lower in early-stage OC patients (FIGO I/II) when compared to healthy controls for all-trans-retinoic acid, 25-hydroxycholecalciferol, all-trans-retinol, astaxanthin, zeaxanthin, lycopene and α-carotene, respectively. In patients with advanced-stage of OC (FIGO III/IV) the mean serum concentrations of carotenoids and FSVs were significantly lower than in healthy controls, excluding lutein and β + γ-tocopherol levels. Patients with OC and concomitant moderate or severe malnourishment showed significantly lower levels of 25-hydroxycholecalciferol and all-trans-retinol. It seems that our extraction and measurement methods for the bioactive compounds could be used in both, clinical and nutritional studies. The obtained results confirm that the PG-SGA assessment might be considered not only as a malnutrition assessment tool, but also for planning early nutritional intervention in patients with OC.

Exposure of heavy metals in coal gangue soil, in and outside the mining area using BCR conventional and vortex assisted and single step extraction methods. Impact on orchard grass

It was investigated that toxic metals (cadmium and lead) enhanced in coal gangue soil used for the reclamation of soil, creates adverse impacts on atmosphere. Presently the chemical fractionation of toxic metals in coal, inner and outer coal gangue soil samples of Lakhra coalfield were studied along with the impact on the orchard grass grown on coal gangue soil in a subside land of the coal mining area. The BCR sequential extraction scheme (BCR-SES) was carried out to determine the different chemical profiles of heavy metals in coal and coal gangue soil samples. For comparative purpose time saving conventional single step extraction (CSE) and vortex assisted single step extraction (VSE) schemes based on same working setting used BCR extraction scheme. The all three procedures were validated by a certified soil sample (BCR 483) and standard addition method in real samples. The total Cd and Pb in coal, soil and grass samples were determined prior to oxidize by acid mixture. The separation of each fraction of Cd, and Pb in all types of environmental samples by VSE could be completed in 30-120s. The extracted Cd and Pb concentrations in reducible fractions by CSE and VSE extraction procedure were 2.5-5% higher than those values gained through BCR-SES. About 71 and 50% of Cd and Pb in coal samples were observed in acid soluble, reducible and oxidizable fraction, respectively, whilst rest of Cd and Pb (29 and 50%) were found in residual phase. The orchard grass (Dactylis glomerata) grown on land reclaimed with OSG was analysed, the bioaccumulate Cd and Pb may create adverse impacts on grazing cattle.

Utilization of wheat spike culture to assess Fusarium head blight disease progression and mycotoxin accumulation

Fusarium head blight (FHB) caused by Fusarium graminearum Schwabe is a major disease of wheat (Triticum aestivum L.). FHB preferentially infects immature spikes and mycotoxins accumulate in developing grains, reducing yield and nutritional quality. The mycotoxins are type B trichothecene group of compounds including deoxynivalenol (DON), 3-acetyldeoxynivalenol (3-ADON), 15-acetyldeoxynivalenol (15-ADON), and nivalenol (NIV) that also act as virulence factors during FHB infection and disease progression. An enzyme UDP-glucosyl transferase (EC 2.4.1.x) glycosylates DON to deoxynivalenol-3-glucoside (D3G), thus rendering it ineffective as a virulence factor. The present study analysed the association of DON, 3A-DON, and D3G with FHB severity using in vitro spike culture for FHB screening. The mycotoxins in FHB-resistant and -susceptible spikes were extracted using a single step extraction method, and their concentration was determined using an LC-MS/MS method that differentiated all the five mycotoxins. Pairwise comparisons of FHB-resistant and -susceptible spike culture derived variants (SCDV) using Tukey’s method showed significant (P ≤ 0.001) variation for disease severity and accumulation of DON, 3-ADON, and D3G at seven and nine days after fungal inoculation. FHB severity showed a significant positive correlation to the accumulation of DON, 3-ADON, and D3G, but an inverse correlation to the ratio between D3G and DON.

Assessing the uptake of selenium from naturally enriched soils by maize (Zea mays L.) using diffusive gradients in thin-films technique (DGT) and traditional extractions

A generally accepted method to predict selenium (Se) bioavailability of long-term contaminated soils has not yet been established, even if risk assessments in selenosis areas are crucial. In this study, a set of methods were tested to assess the bioavailability of Se to field maize. Fifty maize (Zea mays L.) samples and corresponding soils were collected from a selenosis area (Ziyang, China). The diffusive gradients in thin-films (DGT) technique and the traditional chemical extraction methods, including seven single-step extraction procedures and a five-step sequential extraction were used to predict the bioaccumulation of Se in plant. The result verified the presence of 50% of total Se in the form of residual Se fraction, followed by organic-bound and Fe-Mn oxide-bound Se fractions in soil. In addition, Se6+, Se4+, and Se2− were all detected in the solution extracted by H2O, KCl, phosphate-buffered solution (PBS), NaHCO3, ethylenediaminetetraacetic acid-2Na (EDTA-2Na) and ammonium bicarbonate–diethylenetriaminepentaacetic acid (AB-DTPA), but Se6+ was not extracted by NaOH. The Se extracted by single-step extraction methods was weakly correlated with the Se uptake by plants with relatively high Se concentration (>3 mg·kg−1). The abilities of the tested methods to predict Se bioavailability in naturally Se-enriched soils declined in the following order: DGT > soil solution > PBS > KCl > H2O > NaHCO3 > EDTA > DTPA > NaOH. The ratio of CDGT to soil solution Se (Csoln) totaled 0.13, indicating an extremely low Se supply from the soil solid phase to the soil solution. Se measured by DGT was mainly derived from the soluble and exchangeable Se fractions that can accurately reflect the plant-absorbed Se pool. Therefore, the DGT technique is highly applicable in the simultaneous prediction of Se bioavailability in naturally Se-enriched soils.

A High-Throughput Method for the Analysis of Erythrocyte Fatty Acids and the Omega-3 Index.

Omega-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) have several health benefits. In particular, low n-3 LCPUFA status is associated with cardiovascular disease (CVD) and led to the development of the omega-3 index that is the proportion of eicosapentaenoic acid and docosahexaenoic acid in the erythrocyte membranes, as a marker of CVD risk. Most methods used to measure the omega-3 index are laborious and time consuming. Therefore, the aim of this study was to develop a high-throughput method for the extraction and measurement of erythrocyte fatty acids and the omega-3 index. For sample extraction and quantification, two methods were used; a single-step extraction, degradation, and derivatization method by Lepage and Roy, followed by gas chromatography flame ionization detection (GC-FID), which is commonly used and a high-throughput method using an automated methyl tert-butyl ether extraction followed by electrospray ionization mass spectrometry. Both methods were first applied to the analysis of known concentrations of synthetic phospholipid (PL) mixtures to determine recovery and precision prior to their application in the analysis of human erythrocytes. The range of recoveries over five synthetic PL mixtures were 86.4-108.9% and the coefficient of variation was <10% (within-run) and ≤15.2% (between-run). Both methods showed high correlation (R = 0.993) for the omega-3 index and there was no systematic bias in the detection of omega-3 index using either method. The new high-throughput method described here offers considerable advantages in terms of simplicity and throughput compared to the GC-FID method and provides additional information on molecular PL concentrations.

Selective Separation of Chromium Species from Soils by Single-Step Extraction Methods: a Critical Appraisal

A critical appraisal of single-step extraction procedures of chromium species from soil was done in terms of their selectivity towards Cr(III) and Cr(VI) species. Samples of natural mineral and organic soil and samples of soil enriched with different chromium compounds of various solubility (in liquid or solid form) were used to simulate contamination of soil by liquid and solid wastes. The efficiency of extraction of Cr(III) and Cr(VI) species with various reagents, e.g. acetic acid, chelating agents (EDTA, DTPA) or inorganic salts (phosphates and carbonates), was evaluated on the basis of recovery results obtained for enriched samples. None of used reagents allow for quantitative extraction of added Cr(III) form. Procedures based on extraction of soil with Na2CO3 at room and elevated temperature (90–95 °C) were suitable for extraction of Cr(VI) species from mineral soil, whereas for organic soil, the procedure based on extraction with Na2CO3 at room temperature was recommended. The developed extraction procedures were validated using certified reference material (CRM 041 soil) and applied for analysis of contaminated soil samples. The studies showed that the physical state of waste, initial form and oxidation state of chromium and soil properties influenced the final chromium species and their mobility in soil, which have an impact on contamination of environment. The analysis of contaminated soil samples from a tannery area showed that the share of Cr(VI) was very low (only 0.8–4.5%) despite the high total content of chromium, which confirmed that chromium was present in immobile forms.

Comparison of in situ DGT measurement with ex situ methods for predicting cadmium bioavailability in soils with combined pollution to biotas.

To assess the capabilities of the different techniques in predicting Cadmium (Cd) bioavailability in Cd-contaminated soils with the addition of Zn, one in situ technique (diffusive gradients in thin films; DGT) was compared with soil solution concentration and four widely used single-step extraction methods (acetic acid, EDTA, sodium acetate and CaCl2). Wheat and maize were selected as tested species. The results demonstrated that single Cd-polluted soils inhibited the growth of wheat and maize significantly compared with control plants; the shoot and root biomasses of the plants both dropped significantly (P < 0.05). The addition of Zn exhibited a strong antagonism to the physiological toxicity induced by Cd. The Pearson correlation coefficient presented positive correlations (P < 0.01, R > 0.9) between Cd concentrations in two plants and Cd bioavailability indicated by each method in soils. Consequently, the results indicated that the DGT technique could be regarded as a good predictor of Cd bioavailability to plants, comparable to soil solution concentration and the four single-step extraction methods. Because the DGT technique can offer in situ data, it is expected to be widely used in more areas.

Matrix solid-phase dispersion followed by liquid chromatography tandem mass spectrometry for the determination of selective ciclooxygenase-2 inhibitors in sewage sludge samples

A straightforward single-step extraction method based on matrix solid-phase dispersion (MSPD), followed by high-performance liquid chromatography with hybrid quadrupole time of flight mass spectrometry (LC–QTOF-MS), was developed and optimized to determine five non-steroidal anti-inflammatory drugs (Valdecoxib, Etoricoxib, Parecoxib, Celecoxib and 2,5-Dimethylcelecoxib) in sewage sludge samples. The influence of different operational parameters on the extraction efficiency a well as in the matrix effects of the produced extracts was evaluated in detail. Under final working conditions, freeze dried samples (0.2g) were first soaked with 100μL of aqueous potassium hydroxide solution (60%, w/v), mixed with 1g of anhydrous sodium sulfate and dispersed with 1g of Florisil. This blend was transferred to the top of a polypropylene column cartridge containing 3g of silica. Analytes were recovered using 15mL of hexane/acetone (1:2, v/v) mixture. The extracts were concentrated by evaporation and reconstituted with 1mL of methanol/water (1:1, v/v), filtered and injected in the LC system. Quantification limits from 0.005 and 0.05ngg−1 and absolute recoveries between 86 and 105% were achieved. Results indicated the presence of two of the targeted COXIBs in real samples of sewage sludge, the highest average concentration (22ngg−1) corresponding to celecoxib. Moreover, the screening capabilities of the LC–QTOF-MS system demonstrated that the developed MSPD extraction procedure might be useful for the selective extraction of some other pharmaceuticals (e.g. amiodarone and their metabolite N-desethylamiodarone, miconazole, clotrimazole and ketoprofen) from sludge samples.

Assessment of metal bioavailability in the vineyard soil-grapevine system using different extraction methods

This study was focused on the assessment of single and sequential extraction methods to predict the bioavailability of metals in the vineyard soil-grapevine system. The modified BCR sequential extraction method and two single-step extraction methods based on the use of EDTA and acetic acid were applied to differently amended vineyard soils. The variety effect was studied on the uptake of metals by leaves and grapes. Most of the elements studied (Ca, Mg, Cu, Fe, Mn, Zn and Pb) were weakly mobilized from vineyard soils, with the exception of Cu and Mn. The determination of total metal content in leaves and grapes showed a different accumulation pattern in the two parts of the vine. A significant relationship was observed, for all the elements studied except for Fe, between the content bioavailable in the soil and the accumulated in both leaves and grapes (R=0.602–0.775, p<0.01).

Single-step Method for the Extraction of Mucilage from Ocimum americanum L. Seeds

In this work, a single-step extraction method for removing the mucilage present in Ocimum americanum L. seeds was studied. The effect of various parameters on the yield of mucilage such as seed water ratio, speed of the agitator and temperature was also studied. Initially all the experiments were conducted in a 0.5-L glass beaker, and optimum parameters were determined. It was observed that temperature, speed and seed water ratio play an important role in the yield of mucilage. Then the experiments were extended in a 1.5-L stainless steel vessel designed for the above purpose. The kinetics of mucilage extraction at optimum conditions were also studied. It was found that there was a linear relationship exists between the yield of mucilage and time. The study further reveals that at optimum conditions almost complete recovery of mucilage will be possible within 50 minutes of extraction process.

Comparison of diffusive gradients in thin film technique with traditional methods for evaluation of zinc bioavailability in soils.

The technique of diffusive gradients in thin film (DGT) has been shown to be a promising tool to assess zinc (Zn) bioavailability in soils, but there exists considerable debate on its suitability. In this study, Zn bioavailability was systematically investigated in wheat- and maize-grown soils using this technique and seven traditional methods, including soil solution concentration and six widely used single-step extraction methods (HAc, EDTA, NaAc, NH4Ac, CaCl₂, and MgCl₂). The concentrations of Zn in the shoots and roots of these two plant species increased continuously with increasing additions of Zn to the soils, accompanied by significant decreases in shoot biomass and root biomass at Zn concentrations greater than 400 mg kg(-1) for maize and 800 mg kg(-1) for wheat. Zinc uptake and accumulation was higher in maize roots than in wheat roots. Both the concentrations of bioavailable Zn measured by DGT (CDGT) and soil solutions (Csol) increased linearly with increasing additions of Zn to the soils, while no strong linear relationships were observed for the extraction methods. Higher concentrations of extractable Zn, lower values of Csol, and larger values of R (i.e., the ratio of CDGT to Csol) were observed in maize-grown soils compared with those of wheat-grown soils, while the values of C DGT between the two plants were similar. These findings demonstrate that there likely exists a stronger resupply of Zn from the soil solid phases in maize-grown soils to satisfy a higher Zn uptake and accumulation in this plant. Linear correlation analyses showed that CDGT had the highest correlation coefficients with plant Zn concentrations compared with other traditional methods, implying that the DGT technique is more sensitive and robust in reflecting Zn bioavailability in soils to plants.