Extraction of sediment-bound chlorinated organic compounds: implications on fate and hazard assessment

1996 ◽  
Vol 33 (6) ◽  
pp. 247-254 ◽  
Author(s):  
Mark T. Prytula ◽  
Spyros G. Pavlostathis
Keyword(s):  
Solvent Extraction ◽  
Hazard Assessment ◽  
Extraction Efficiency ◽  
Soxhlet Extraction ◽  
High Water ◽  
Extraction Methods ◽  
High Water Content ◽  
Chlorinated Organic Compounds ◽  
Sediment Samples ◽  
Sediment Fraction

Five methods were used for the extraction of hexachlorobutadiene and chlorobenzenes from a contaminated estuarine sediment. The following extraction methods were used: Soxhlet extraction, sonication and solvent extraction, sequential solvent extraction, saponification and solvent extraction, and supercritical fluid extraction. Soxhlet extraction resulted in better contaminant extraction efficiency and reproducibility. Most of the problems associated with the extraction methods were related to high water content and the inherent heterogeneity of the sediment samples. Drying and grinding of the sample greatly improved both extraction efficiency and reproducibility. Analyses of wet sieved and fractionated sediment samples indicated that the contaminants are not evenly distributed throughout the sediment organic fraction but rather predominate in the larger particle sediment fraction. The implications of quantification difficulties of sediment contaminants on the environmental fate and hazard assessment are discussed.

Comparison of extraction efficiency of various methods to extract L-DOPA from Mucuna pruriens (L.) DC.

2017 ◽  
Vol 6 (04) ◽  
pp. 5343
Author(s):  
Ragni Vora ◽  
Ambika N. Joshi* ◽  
Nitesh C. Joshi
Keyword(s):  
Extraction Efficiency ◽  
Soxhlet Extraction ◽  
Extraction Methods ◽  
Mucuna Pruriens ◽  
Water Mixture ◽  
Uv Detector ◽  
Pharmacological Activities ◽  
Hplc Mobile Phase ◽  
Plant Sources ◽  
Seed Extracts

Mucuna pruriens seeds are noted to be a natural source of L-DOPA and are also used as a substitute for the synthetic L-DOPA. In the present study; attempts are made to develop suitable method(s) for extraction of L-DOPA from the powdered seeds of Mucuna pruriens using different solvents and conditions. The Seed powder was subjected to 7 different extraction methods and Method 1 was subjected to various solvent concentrations. Some methods used de-fatting procedure, either the method was cold maceration or in high temperature. Soxhlet extraction was also used in one of the extraction methods. All the extracts were analyzed using RP-HPLC. Mobile Phase used was Water: Methanol: AcetoNitrile (100:60:40) (v/v) containing 0.2% Triethylamine, pH = 3.3 and monitored at 280 nm with variable wavelength UV detector. The extraction was best with Methanol Water mixture in a cold maceration technique and overall gives good extraction efficiency of 13.36 % L-DOPA and id the best method giving highest extraction efficiency. The De-fatting method was the 2nd best methods giving approximately 8.8% L-DOPA and Method 5 viz, heat reflux method gives 8.7% L-DOPA making it the 3rd best method. There are not many studies done for optimization of extraction technique for L-DOPA despite an extensive work is reported for isolation, identification and pharmacological activities of L-DOPA from various plant sources. Keeping this in view, present investigation was done to study the extraction efficiency of various extraction methods of L-DOPA content in seed extracts of Mucuna pruriens and compare it.

scholarly journals Application of Direct Solvent Extraction to the LC Quantification of Vitamin E in Peanuts, Peanut Butter, and Selected Nuts

1998 ◽  
Vol 25 (2) ◽  
pp. 123-128 ◽  
Author(s):  
J. Lee ◽  
W. O. Landen ◽  
R. D. Phillips ◽  
R. R. Eitenmiller
Keyword(s):  
Vitamin E ◽  
Solvent Extraction ◽  
Peanut Butter ◽  
Extraction Procedure ◽  
Soxhlet Extraction ◽  
Extraction Methods ◽  
Normal Phase ◽  
The Other ◽  
Direct Solvent Extraction ◽  
Peak Purity

Abstract Direct solvent extraction with hexane:ethyl acetate (90:10, v/v), saponification, and Soxhlet extraction with hexane were evaluated for their usefulness as extraction methods to determine vitamin E in peanuts and peanut butters. The direct solvent extraction procedure yielded higher values for each tocopherol homolog in peanut and peanut butter compared to the other methods. Coupling of the rapid, direct solvent extraction with normal phase chromatography on Si 60 provides a highly reproducible procedure to quantitate vitamin E in peanuts and peanut products. The overall % recoveries (means ± S.D.) of this study for α-, β-, γ-, and δ-tocopherol were 99.9 ± 3.29, 100.4 ± 11.7, 98.9 ± 5.94, and 100.3 ± 4.87, respectively. Limits of detection and limits of quantitation were 0.21, 0.06, 0.11, and 0.08 ng and 0.39, 0.14, 0.23, and 0.13 ng, respectively, for α-, β-, γ-, and δ-tocopherol. Repeatability, reproducibility, and accuracy of the methods were excellent with % CVs for accuracy of 1.19 (α-T), 1.55 (γ-T), and 2.69 (δ-T). Accuracy was not acceptable for β-T due to its extremely low concentration in the peanut and because peak purity was not obtained for β-T. The method was applied to other seeds with good success. Major homologs were γ-T in peanuts, pecans, cashews, walnuts, and pistachio; α-T in almonds; and α-T3 in macadamia.

scholarly journals IR spectroscopy for analysing solvent extraction efficiency of oil extracts

2022 ◽  
Vol 11 (4) ◽  
pp. 673-680
Author(s):  
V. I. Zholnerkevich ◽  
E. I. Grushova
Keyword(s):  
Solvent Extraction ◽  
Ir Spectroscopy ◽  
Ethylene Glycol ◽  
Extraction Efficiency ◽  
Triethylene Glycol ◽  
Extraction Methods ◽  
The European Union ◽  
Polycyclic Aromatic ◽  
Aromatic Components ◽  
Oil Extract

Solvent extraction is a method for purifying oil extracts, which are used as oil-plasticisers for industrial rubber goods, from cancerogenic hydrocarbons. The efficiency of this method is mainly determined by the selectivity and solvent properties of a separating agent. However, when carrying out a comparative analysis of promising extraction methods, it is necessary to use real-time methods for studying the composition of the resulting products. The purification efficiency of oil extracts from polycyclic aromatic components, including carcinogenic hydrocarbons (benzo[a]pyrene, benzo[e]pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, etc.), was evaluated depending upon the nature of selective solvents. The structure-group composition of the purified oil extracts and those at the second-stage of purification was determined by FTIR spectroscopy. It was found that the extraction efficiency of the studied solvents towards polycyclic aromatic hydrocarbons from oil extracts increases in the following order: dimethyl sulfoxide < N-methylpyrrolidone + 10 wt% ethylene glycol <N-methylpyrrolidone +50 wt% triethylene glycol. When using a solvent comprising N-methylpyrrolidone + 50 wt% triethylene glycol, the proportion of polyalkyl-substituted and condensed aromatic structures in the purified oil extract decreases by 16.8%; the oil extract yield increases by over 25 wt% in contrast to extraction with N-methylpyrrolidone + ethylene glycol mixture, which meets the requirements of the European Union for oil extract purification (Directive No. 2005/69/EC). Therefore, we recommend the solvent comprising N-methylpyrrolidone + 50 wt% triethylene glycol for purifying oil extracts from components having a technogenic impact on the environment and human health and IR spectroscopy for efficiency assessment of solvent extraction of oil extracts.

Study on Extraction Efficiency of Coal with Different Methods

2013 ◽  
Vol 699 ◽  
pp. 841-845
Author(s):  
Hong Yang ◽  
Wen Yan Bi ◽  
Yu Gui Zhang ◽  
Hou Xiang Chen ◽  
Hua Hu ◽  
...  
Keyword(s):  
Coal Mine ◽  
Bituminous Coal ◽  
Extraction Efficiency ◽  
Soxhlet Extraction ◽  
Extraction Methods ◽  
Extraction Time ◽  
Environmental Friendly ◽  
Tectonic Coal ◽  
Time Required ◽  
Fast Extraction

To raise the extraction efficiency of the organic components of coal, samples were selected from tectonic coal and original bituminous coal in symbiotic seam of coal in Pingdingshan 8th coal mine and 5th coal mine. For comparing the extraction time required under the same extraction rate, two different extraction methods, ultrasonic-microwave coordination extraction and traditional soxhlet extraction, was adopted. The experimental results showed that the extraction proportion of ultrasonic-microwave coordination extraction was 10.7911% when adopted tectonic coal of 8th coal mine as sample, selected 80mL pyridine as solvent, set 95W as microwave power and 3min as extraction time. Under the condition of same extraction proportion, soxhlet extraction time is 39.43h.So the extraction efficiency of the ultrasonic-microwave coordination extraction was as 788.6 times as soxhlet extraction. The ultrasonic-microwave coordination extraction was a simplify method with fast extraction speed, large volume sample, energy saving and environmental friendly.

scholarly journals Assessment of Green Solvents and Extraction Methods for Biopesticide Preparation from Neem Azadirachta indica Leaves against Oriental Fruit Fly Bactrocera dorsalis (Hendel)

2018 ◽  
Author(s):  
Danila S. Paragas ◽  
Kathlia Cruz ◽  
Elaida R. Fiegalan
Keyword(s):  
Solvent Extraction ◽  
Soxhlet Extraction ◽  
Extraction Methods ◽  
Green Technology ◽  
Bactrocera Dorsalis ◽  
Distilled Water ◽  
Green Solvents ◽  
Active Components ◽  
Leaf Extracts ◽  
Neem Leaves

This study was conducted to search for green technology that can extract metabolites from neem leaves for use in the development of botanical pesticide against Bactrocera dorsalis (Hendel) (Diptera:Tephritidae). Rice wine, rice wash, vinegar and distilled water were used as solvents and hot infusion, maceration, hot continuous reflux (Soxhlet), and fermentation were the methods employed. The different leaf extracts prepared by green technology were evaluated for their potentials as pesticide against B. dorsalis. Vinegar extract via Soxhlet extraction (V-S) for eight (8) h registered to have the highest mortality but not significantly different from vinegar - fermentation (V-F), rice wash - Soxhlet (RWa-S), vinegar - maceration (V-M), distilled water - fermentation (DW-F), and rice wash - fermentation (RWa-F) extracts. Phythochemicals present in the extracts are affected by the solvent-extraction interaction. Among the sixteen solvent-extraction interactions, the use of rice wash and fermentation is the most economical method in extracting the extracting the active components of neem leaves against B. dorsalis. Rice wash is a waste that can be utilized in the development of a biopesticide from neem leaves for pest management of B. dorsalis. This is the first report that rice wash is used as extracting solvent in green synthesis.

Laboratory sound speed measurements on high water content sediment samples

2008 ◽  
Vol 123 (5) ◽  
pp. 3595-3595
Author(s):  
Vanessa A. Martin ◽  
Alain Alexis ◽  
Vincent Martin
Keyword(s):  
Water Content ◽  
Sound Speed ◽  
High Water ◽  
High Water Content ◽  
Sediment Samples

Features of spring feeding of sterlet of the middle course of the Northern Dvina river

2020 ◽  
pp. 8-17
Author(s):  
A. Bykov ◽  
D. Palatov ◽  
I. Studenov ◽  
D. Chupov
Keyword(s):  
Benthic Communities ◽  
High Water ◽  
Food Composition ◽  
Fish Growth ◽  
High Water Content ◽  
Feeding Intensity ◽  
Biting Midges ◽  
Size Groups ◽  
Main Components ◽  
A Minor

The article provides information about the features of spring feeding of sterlet in the spawning grounds of the middle course of the Northern Dvina river in may 2019. The main and secondary groups of forage objects in the diet of this species of sturgeon are characterized. The article considers the variability of the sterlet food composition with an increase in the size of fish from 30 to 60 cm. In the process of fish growth in the diet of the Severodvinsk sterlet, the main components in terms of occurrence and mass in all size groups are the larvae of Brooks and chironomids. A minor occurrence was the larvae of midges, biting midges, stoneflies, mayflies and small clams. To random and seasonal food are the larvae of water bugs, butterflies, flies, beetles and eggs of other fish. The feeding intensity of the smaller sterlet (30–40 cm) was significantly higher than that of the fish in the size groups 40–50 and 50–60 cm. Fundamental changes in the diet of the Severodvinsk sterlet for the main food objects for more than sixty years of observations have not been established. During periods of high water content of the Northern Dvina due to seasonal changes in the structure of benthic communities, the value of Brooks in the diet of sterlet increases and the proportion of chironomids decreases.

Comparison of Sorption and Extraction Methods for Recovery of Trace Organics from Water

1983 ◽  
Vol 15 (6-7) ◽  
pp. 149-159 ◽  
Author(s):  
V C Blok ◽  
G P Slater ◽  
E M Giblin
Keyword(s):  
Solvent Extraction ◽  
Methylene Chloride ◽  
Extraction Methods ◽  
Liquid Extraction ◽  
Standard Mixture ◽  
Liquid Liquid Extraction ◽  
Trace Organics ◽  
Tenax Gc

Several commercially available adsorbents were compared with solvent extraction methods for their utility in recovering trace organics from water. The adsorbents examined included Amberlite XAD-2, XAD-4 and XAD-8, Ambersorb XE340 and XE348 and Tenax-GC. All were found to produce high artifact levels, even after extensive clean-up, making them unsuitable for the analysis of trace organics in water. Quantitatively, Likens-Nickerson or continuous liquid-liquid extraction with méthylene chloride gave better recoveries than the adsorbents. Qualitatively, extractive methods were preferred as they yielded much lower levels of impurities than the adsorbents. These methods of recovering trace organics were evaluated using a standard mixture of compounds added to the water at a level of 55 µg/l. Likens-Nickerson extraction gave comparable recoveries of this mixture at 55 µg/l and 11 µg/l.

Hydrogels as Antibacterial Biomaterials

2018 ◽  
Vol 24 (8) ◽  
pp. 843-854 ◽  
Author(s):  
Weiguo Xu ◽  
Shujun Dong ◽  
Yuping Han ◽  
Shuqiang Li ◽  
Yang Liu
Keyword(s):  
Mechanical Properties ◽  
Drug Delivery ◽  
Tissue Engineering ◽  
Water Content ◽  
Oxygen Permeability ◽  
Structural Diversity ◽  
High Water ◽  
Clinical Applications ◽  
High Water Content ◽  
Biomedical Field

Hydrogels, as a class of materials for tissue engineering and drug delivery, have high water content and solid-like mechanical properties. Currently, hydrogels with an antibacterial function are a research hotspot in biomedical field. Many advanced antibacterial hydrogels have been developed, each possessing unique qualities, namely high water swellability, high oxygen permeability, improved biocompatibility, ease of loading and releasing drugs and structural diversity. In this article, an overview is provided on the preparation and applications of various antibacterial hydrogels. Furthermore, the prospects in biomedical researches and clinical applications are predicted.

Quantitative GC-FID and UHPLC-DAD Evaluation of Bioactive Compounds Extracted from Ginkgo biloba

2020 ◽  
Vol 16 (7) ◽  
pp. 893-904
Author(s):  
Alessandra von Ahn ◽  
João Henrique Z. dos Santos
Keyword(s):  
Ginkgo Biloba ◽  
Extraction Efficiency ◽  
Extraction Methods ◽  
Ginkgo Biloba Extract ◽  
Previous Method ◽  
Array Detector ◽  
Ginkgolide B ◽  
Detection Techniques ◽  
Ginkgolide A ◽  
Terpene Trilactones

Background: The official compendium of the quantification of ginkgo flavonoids from Ginkgo biloba extract has been proposed using HPLC. The drawbacks of this technique appear to be due to the restricted efficiency in terms of the recovery results and suitability of the system for the quantification of these compounds. This study investigated the potential advantages and limitations of the development of efficient extraction methods for the recovery of flavonol glycosides (quercetin, kaempferol and isorhamnetin) and terpene trilactones (bilobalide, ginkgolide A, ginkgolide B and ginkgolide C) using extraction, quantification and detection techniques, namely, GC-FID and UHPLC-DAD, which are alternatives to those techniques available in the literature. Methods: Two different extraction methodologies have been developed for the determination of flavonoids (quercetin, kaempferol and isorhamnetin) and terpene trilactones (bilobalide, ginkgolide A, ginkgolide B and ginkgolide C) using ultra-high-pressure liquid chromatography coupled to a diode array detector and gas chromatography coupled to a flame ionization detector. Results: In this study, the Ginkgo biloba extract mass, hydrolysis preparation method (with or without reflux), and volume of the extraction solution seemed to affect the ginkgo flavonoid recovery. The UHPLC-based method exhibited higher extraction efficiency for ginkgo flavonoid quantification compared to the pharmacopoeial method. The developed method exhibited higher extraction efficiency for terpene quantification compared to the previous method that used extractive solution without pH adjustment, with less time of extraction and less amount of the sample and organic solvent aliquots. Conclusion: The UHPLC and GC analysis methods established in this study are both effective and efficient. These methods may improve the quality control procedures for ginkgo extract and commercial products available in today´s natural health product market. The results indicate that redeveloped extraction methods can be a viable alternative to traditional extraction methods.

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