Hot Soxhlet Extraction Research Articles

Evaluation of environmental contamination in beeswax products

Beeswaxes are used as a coating agent or as a wrapping material for food products making them potentially ingested by consumers. There is no regulation yet in Europe giving maximum levels of contaminants in this type of product. Nevertheless, being a natural product, they are exposed to environmental pollution, thus it appears necessary to establish their contamination rate in order to evaluate potential human exposure. In this study, a method of extraction of different environmental contaminants including pesticides, phthalates, PAHs and phenols was developed. Based on a hot Soxhlet extraction, followed by cleaning steps, the method was validated for the quantitation of the cited contaminants by LC-MS/MS and GC-(MS)/MS.Three different types of waxes were analyzed including typical white waxes (Cera Alba) and yellow waxes (Cera Flava). It was shown that all waxes had the presence of at least one contaminant and that phthalates, in particular DEHP, was present in all beeswax samples. Insecticides were found in majority among all the classes of pesticides screened. The yellow waxes were found to be contaminated with the highest rates of PAHs (60%), pesticides (75%) and phenols (40%). The detection frequency of PAHs, in contrast to phthalates, was the lowest for all the types of waxes combined.

Qualitative, Quantitative, In Vitro Antioxidant Activity and Chemical Profiling of Leptadenia pyrotechnica (Forssk.) Decne Using Advanced Analytical Techniques.

Leptadenia pyrotechnica Forssk. Decne (LP) is a medicinal herb from the Asclepiadaceae family with many advantageous properties. The goal of this research is to identify, quantify, and evaluate the antioxidant potential of LP to validate its remarkable therapeutic advantages. The hot soxhlet extraction method was employed to prepare different extracts of LP (stem and root). These extracts were evaluated physiochemically to check their impurity, purity, and quality; qualitatively to detect different phytochemicals; and quantitatively for phenol, saponin, tannin, flavonoid, and alkaloid contents. Then, the in vitro antioxidant potential was estimated by DPPH, NO, H2O2 scavenging assays, and MC and FRAP assays. The most prevalent phytochemicals of LP were then analysed by AAS, FT-IR, UV-visible, and GC-MS techniques. A higher extractive yield was shown by LPSE and LPRE (7.37 ± 0.11 and 5.70 ± 0.02). The LP stem showed better physicochemical and qualitative results than the root. The quantitative and in vitro antioxidant results indicated maximal phenols, tannins, and alkaloid contents in LPSE, which was further confirmed by UV-visible, FT-IR, and GC-MS results. The extraction methods (soxhlation or ultrasonication) were optimized by utilizing RSM to determine the impacts of multiple parameters. The study concluded that the plant has remarkable therapeutic advantages to promote additional clinical investigations and the mechanisms of its action.

In Vitro investigating the antidiabetic activity of Rumex abyssinica, Hibiscus sabdariffa, and Cinnamomum zeylanicum

Background: Diabetes is a metabolic disorder symptomized by high blood glucose level.The treatment is associated with adverse side-effects regarding health and economic burdens of the diseased. The difficulty in insulin injection, the non-compliance, prolonged treatment, makes to the diabetic patients to have a poor controlled blood glucose level particularly in resource limited settings. As alternative, people are using medicinal plants as they are cheap, readily available, and lesser side effects. Even though the need for herbal medicine are culturally and socially accepted but the toxicity ,active principles, and mechanism of action are generally not known well so this study aims to investigate in vitro potential effects of Rumex abyssinica, Hibiscus sabdariffa, and Cinnamomum zeylanicum in glucose regulation. Methodology: Different parts from the 3 plants were subjected to hot Soxhlet extraction using solvents with different polarity. The in vitro anti-diabetic activity of the extracts was investigated by measuring their effect on assays of α-amylase inhibition and glucose transport across yeast cells. Result: The result of α-amylase inhibition reveled highest, significant (p0.001) from aqueous extracts (0.5 mg/ml) of Hibiscus sabdariffa and Rumex abyssinica by 85.11%, and 77.91% respectively.Though chloroform extract of Cinnamomum zeylanicum was not significant exhibited 92.49% α-amylase inhibition at 0.5 mg/ml. In the glucose transport assay, the aqueous extract (0.5 mg/ml) of Cinnamomum zeylanicum, Hibiscus sabdariffa, and Rumex abyssinica increased glucose transport across yeast cells by 52.44%, 52.16%, and 50.57% respectively, at 25mM glucose concentration. Conclusion: All the three selected medicinal plants were found to have an effective inhibition of α-amylase and glucose absorption by the aqueous extract. This shows that the plants extract contains an active water-soluble ingredients which may have anti-diabetic activity in vivo when taken in the form of tea. Therfore, we kindly recommend that , a further invivo, toxicological, phytochemical, and molecular analysis of these plants to be conducted in case control stdudies as it has been used as tea in the community.

Phytochemical Screening of Petroleum Ether Fractions by GC/MS and Isolation of Lupeol from Two Different Parts of Iraqi Leucaena leuco-cephala. (Conference Paper )#

Abstract This work is considered the first study for the components of the Iraqi Leucaena leucocephala plant, where the different phytochemical compounds that present in the aerial parts were identified by using the gas chromatography/mass spectrometry technique (GC/MS). The type of the components and their concentration will differ according to the part of the plant used and the method of extraction (hot and cold). This study made a comparison in lupeol concentration that was identified and isolated from petroleum ether fractions of Leucaena leucocephala by using Gas Chromatography/Mass Spectrometry (GC/MS), High-performance thin-layer chromatography (HPTLC), and Preparative High-Performance Liquid Chromatography (P-HPLC). The plant leaves and stems were collected in September, dried under shade, and powdered (separately), then extracted by two extraction methods: hot Soxhlet and cold maceration method using 85% ethanol, then the result crude extract was fractionation with petroleum ether by using a separator funnel. The results of GC/MS, HPTLC, and PHPLC indicated that the leaves contain a higher concentration of lupeol than the stems and the cold maceration method is more efficient than the hot Soxhlet extraction method. Lupeol has many pharmacological activities applied in alternative medicine such as anti-inflammatory, antimicrobial, anti-arthritic, anticancer, antidiabetic, and antioxidant activities with wide future applications.

Molecular Characterization of Polar Compounds in Crude Oil Affecting Sandstone Wettability Revealed by Fourier Transform-Ion Cyclotron Resonance-Mass Spectrometry

Summary Knowing the composition, molecular size, and structure of polar compounds in crude oil that affect sandstone wettability is a prerequisite for a better understanding of oil/rock/brine interactions and for better application of enhanced oil recovery (EOR) techniques to increase recovery factors and improve the economic efficiency of field development. The nitrogen-, sulfur-, and oxygen-containing polar compounds in crude oil are key factors for sandstone wettability changes. In this study, an outcrop sandstone core selected from Jurassic formation in Sichuan Basin, China, was aged by crude oil to restore the wettability after being cleaned by hot Soxhlet extraction with an azeotropic solvent mixture of methanol and dichloromethane (MDC, vol/vol = 7:93). Then, Amott-Harvey experiments that were conducted by combining spontaneous imbibition and forced displacement steps of coreflooding were performed to characterize sandstone wettability after it was cut into four core blocks. The wettability index (IA-H) of four core blocks from the inlet to outlet of oil flooding were −0.523, 0.214, −0.087, and −0.861, respectively, which illustrated different degrees of sandstone wettability. The extracts of three sequential hot Soxhlet extraction steps of four core blocks were analyzed by gas chromatography-mass spectrometry (GC-MS) and high-resolution Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS) combined with electrospray ionization (ESI) in negative ion mode. Almost no polar compounds were detected in the n-hexane extracts, and a total of seven classes of different polar molecular compounds—namely, N1, N1O1, N1S1, O1, O2, O3, and O4—were detected in dichloromethane (DCM) and MDC extracts. The relative abundances of the N1S1 and O1 classes in the extracts of DCM and MDC were too low to be ignored. Compared to those of polar compounds in DCM extracts, the relative abundance of neutral nitrogen compounds (N1 and N1O1 classes) in the MDC extracts decreased significantly. In contrast, the acidic compounds (O2, O3, and O4 classes) all showed an obvious increase in the MDC extracts compared to the DCM extracts. It was notable that most of the polar compounds in MDC extracts were O2 and O3 compounds with double bond equivalent (DBE) values = 1 from the perspective of DBE distribution. The proportion of these two compound classes was much higher than that of all other polar compounds. Therefore, we believe that these two compound classes are the decisive factors for changing sandstone wettability combined with previous studies. In addition, based on the number of oxygen atoms and DBE values, we inferred that the O2 (DBE = 1) class was the long-chain saturated fatty acids and that the O3 (DBE = 1) class was the hydroxyl acids containing both one carboxyl and one hydroxyl group. Furthermore, the final determination of the wettability degree of the sandstone surface was the amount of all polar compounds, not only the relative abundance of these two types of acids. These two types of acids in crude oil were equivalent to anchor molecules on the surface of sandstone, and other polar compounds were adsorbed onto their surface to make the sandstone preferentially oil-wet.

Automated accelerated solvent extraction method for total lipid analysis of microalgae

For algae-based biofuel researches, it is usually necessary to extract and quantitatively measure total lipids. The most popular total lipid determination methods for tissues are solvent-based methods with either manual or Soxhlet extraction. Although some investigators have modified these traditional methods, the modifications have rarely been specified in detail, nor has their effectiveness been critically evaluated on microalgae biomass. As a result, there are often significant differences in the analyses of total lipid contents among investigators and laboratories. To assess the effectiveness of different total lipid extraction protocols for microalgae, several conventional lipid extraction methods were systematically compared with an accelerated solvent extraction (ASE) method. Optimal conditions for the ASE method were determined to be three cycles of 3 min at 125 °C using a 5 ml extraction cell containing 20 to 150 mg of dry algal biomass. Critical comparisons and assessments of these total lipid extraction methods from microalgae were performed for both total lipid extraction efficiency and extracted lipid quality (lipid decomposition and oxidation). Results obtained from five algal species indicated that hot Soxhlet extraction and ASE were comparable in total lipid extraction efficiencies, which were higher than the efficiencies obtained from conventional manual extraction methods. However, lipid oxidation resulting from different extraction methods indicated that continuous heating with a hot Soxhlet extraction method could lead to lipid oxidation. Considering the efficiency and quality of the extracted lipids, extraction time, extraction steps and consumed solvent volumes, ASE is a very promising method for total lipid extraction and analysis of lipids from microalgal biomass.

In Vitro Inhibition of α-Amylase and α-Glucosidase by Extracts from Psiadia punctulata and Meriandra bengalensis.

Background This research assessed the in vitro antidiabetic activity and phytochemical constituents of the traditionally used medicinal plants, Psiadia punctulata and Meriandra bengalensis. Method The leaves of both plants were subjected to cold extraction method using 70% ethanol and hot Soxhlet extraction using n-hexane, chloroform, methanol, and distilled water. The extracts were studied for their effect on glucose transport across yeast cells and inhibition of α-amylase and α-glucosidase enzyme activities. Thin-layer chromatographic analysis of ethanol extract was also undertaken. Results The results of yeast glucose uptake assay revealed that extracts from both plants had a maximum increase in glucose uptake at the 25mM glucose concentration with a maximum dose of 2000μg/ml plant extract. The ethanol extract of P. punctulata and aqueous extract of M. bengalensis showed a high activity of 68% and 96%, respectively, at 25mM and 2000μg/ml of glucose and extract concentration. P. punctulata exerted peak inhibition activity of α-amylase of 37.5 ± 3% mg/dl (IC50 = 0.523 mg/dl) for methanol and distilled water extract at 0.5 mg/dl, respectively. M. bengalensis methanol extract exhibited the highest inhibition activity of 38 ± 8 % mg/dl (IC50 = 0.543 mg/dl) at 0.5 mg/dl. In the α-glucosidase inhibition assay, the methanolic extract of P. punctulata exhibited the highest inhibitory activity of 17.29 ± 9% mg/dl (IC50 = 0.761 mg/dl) at 0.5mg/dl. The chloroform extract of M. bengalensis had the highest inhibitory activity of 30 ± 5% mg/dl (IC50 = 0.6mg/dl) at 0.5 mg/dL. Phytochemical analysis of the different extracts of P. punctulata and M. bengalensis revealed the presence of flavonoids, alkaloids, tannins, saponins, phytosterols, and carbohydrates. Thin-layer chromatography analysis of ethanolic extract of both plants indicated presence of 15 and 17 spots for P. punctulata and M. bengalensis respectively. Conclusion P. punctulata and M. bengalensis extracts have moderate inhibitory activity against pancreatic α-amylase and relatively low inhibitory activities against α-glucosidase. The observed effects may be associated with the presence of flavonoids, saponins, and alkaloids. Additional in vivo analysis, toxicological studies, isolation, and structural characterization of the phytomolecules identified in this study and molecular docking studies should be undertaken.

Percentage Yield and Acute Toxicity of the Plants Extracts of Ceiba pentandra and Anogeissus leiocarpus Grown in Bauchi State, North Eastern Nigeria

The roots and stem bark of Ceiba pentandra and Anogeissus leiocarpus was subjected to hot Soxhlet extraction using solvent of different polarity, hexane, ethyl acetate, acetone, methanol and water. The methanol extracts gave the highest yield of 17.5% highest polar solvent while hexane being the lowest polar solvent gave the least percentage recovery of 1.12%. The colour and texture of each of the extract was also determined. Hexane and ethyl acetate extract showed yellow and orange colour, with the texture oily and solid. While acetone, methanol and water extracts gave brown and dark brown colour with the texture being solid and pastry. The acute toxicity of the extracts was also determined by using both the oral and interperitoneally dosage concentration. The interperitoneally dosage with slight modification tends to be toxic than the oral dosage.

Percentage Yield and Acute Toxicity of the Plants Extracts of Ceiba pentandra and Anogeissus leiocarpus Grown in Bauchi State, North Eastern Nigeria

The roots and stem bark of Ceiba pentandra and Anogeissus leiocarpus was subjected to hot Soxhlet extraction using solvent of different polarity, hexane, ethyl acetate, acetone, methanol and water. The methanol extracts gave the highest yield of 17.5% highest polar solvent while hexane being the lowest polar solvent gave the least percentage recovery of 1.12%. The colour and texture of each of the extract was also determined. Hexane and ethyl acetate extract showed yellow and orange colour, with the texture oily and solid. While acetone, methanol and water extracts gave brown and dark brown colour with the texture being solid and pastry. The acute toxicity of the extracts was also determined by using both the oral and interperitoneally dosage concentration. The interperitoneally dosage with slight modification tends to be toxic than the oral dosage.

Antibacterial, antioxidant and cell proliferative properties of Coccinia grandis fruits.

Little knowledge is available on the antimicrobial and antioxidant properties of Coccina grandis fruits and no study has reported on its cell proliferative property. The aim of this study was to examine the antimicrobial, antioxidant and cell proliferative property of fruits of C. grandis. Fruits of C. grandis were extracted using water; ethanol and acetone by cold and hot Soxhlet extraction. The antibacterial activities of the extracts were tested against Staphylococcusaureus,Enterococcusfaecalis,Escherichiacoli and Pseudomonasaeruginosa using the modified Kirby-Bauer diffusion method and compared against erythromycin. The antioxidant property was determined using Cayman's antioxidant assay; whereas cell proliferation/cytotoxic properties were evaluated using the Cell Titer 96 Aqueous One Solution Cell MTS assay with MDA-MB 321 breast cancer cells. Data were analyzed for correlation and differences using unpaired student's t-test and one-way ANOVA. A p value of <0.05 was considered statistically significant. Both cold and hot ethanol and acetone extracts of C. grandis fruits showed some degree of bacterial growth inhibition. Acetone extracts exhibited higher antibacterial activity. Both ethanol extracts showed antioxidant property when compared with standard Trolox. In contrary to cytotoxicity, all four extracts showed cell proliferation compared to controls at different concentrations. However, acetone extracts exhibited greater cell proliferation compared to ethanol extracts and cold extracts performed better than the hot extracts. C. grandis fruits exhibited some degree of antimicrobial, antioxidant and cell proliferative properties. Further investigation is warranted to isolate, confirm and characterize phytochemicals that are responsible for the medicinal properties observed.

Pharmacognostic Evaluation, Phytochemical Screening and Antimicrobial Activity of Stem Bark of Ficus Krishnae

Ficus krishnae is a perennial plant, used in number of folklore medicine, to treat ulcer, vomiting, fever, inflammation, diabetes, dysentery, leprosy and cancer etc. The present research deals with the study of pharmacognostic, phytochemical and antimicrobial activity of stem bark of Ficus krishnae. The pharmacognostic parameters for the study were physicochemical, fluorescence analysis and preliminary phytochemical screening along with mineral analysis. In physicochemical evaluation the ash value and extract value were studied. The antimicrobial activity of the stem bark extract against pathogenic strains was evaluated based on the inhibition zone using well diffusion assay; minimum inhibition concentration (MIC) is studied using micro dilution method. The powder of Ficus krishnae was successively extracted with petroleum ether, chloroform, methanol and aqueous by hot soxhlet extraction. The preliminary screening was carried out for different extract. Fluorescence analysis has showed the normal ranges of fluorescence colour for the crude powder. The preliminary phytochemical screening resat also indicated the presence of principle active compounds of Ficus krishnae which include phenols, flavonoids, saponin, alkaloids, glycosides, oils, fats, steroids, proteins and carbohydrates. The inorganic element analysisstudy indicated the presence of calcium, potassium, magnesium, manganese, zinc, molybdenum, vanadium, titanium and cadmium. In the present study we have tested antimicrobial activity of Petroleum ether, chloroform, methanol and Aqueous extractions of stem bark of Ficus krishnae plant against six bacteria (E.coli, Staphylococcus aureus, ENT, Enterococcus fecalis, salmonella typhi,) and one fungi (Aspergillus niger). These studies gives information of physicochemical character and preliminary property of stem bark of Ficus krisnae for the identification of crude drug and it promote the search for isolation of medicinally valuable active compounds.

In vitro anti-inflammatory and skin protective properties of extract comprising ceramides from de-oiled rice bran

De-oiled rice bran is a byproduct of rice processing industries and rich in lipids, carbohydrates, proteins, and fibers. Although rich in nutrients, it is unfit for human consumption and used as animal feed. This study was conducted to explore the therapeutic value of rice bran ceramides. Methanolic extract of de-oiled rice bran (RBE) was obtained by hot soxhlet extraction method and evaluated for presence of ceramide. Further, the rice bran ceramide extract (RBE) was subjected to column chromatography and the presence of ceramide ascertained by spectroscopic studies. Cytotoxic effect of RBE was tested on THP-1 and HaCaT cells. The tested concentrations of RBE (100 and 200 µg/mL) dose-dependently inhibited lipopolysaccharide induced pro-inflammatory cytokines (TNF-α, IFN-γ, IL-8, IL-6, and IL-5) in THP-1 cells. RBE enhanced skin-barrier function (involucrin and filaggrin) in HaCaT cells, up-regulated aquaporin-3 (AQP-3) expression, and inhibited hyaluronidase activity in HaCaT cells. Thus, RBE exhibited significant anti-inflammatory and skin protective benefits in vitro. Practical applications De-oiled rice bran is cheap, easily procurable, rich in phytonutrients, and possess therapeutic value. In the current study, extract comprising ceramides from de-oiled rice bran (RBE) showed significant anti-inflammatory and skin protective effects on THP-1 and HaCaT cells, respectively. The results of the present investigation highlights the promising use of rice bran ceramides as potential anti-inflammatory and skin protective ingredient in nutritional and skin-care formulations or products.

The antimicrobial effect of the Artimisa herba And Eordium glycobhyllum against pathogenic bacteria

Artimisa herba and Erodium antimicrobial activity were used against Serratia spp., Bacillus cereus, E.coli, Micrococcus roseus, Staphylococcus aureus, Streptomyces spp.and Micrococcus lutaus.The method of extraction applied in this paper was the Soxhlet- hot extraction using petroleum ether and alcoholic solvents.The bacterial inhibition by the extract was as follows: Serratia spp was found moderately sensitive to Artimisa herba with failure to produce pigment. B. cereus was found moderately so to Artimisa herba lal, while it showed low response to Artimisa herba. Escherchia coli showed moderate inhibition to Artimisa herba, Micrococcus roseus responded well to and grodium moderately to grodium. Staohylococcus aureus well to moderately to Artimisa herba. Streptomyces spp. responded well only to based on the results obtained in this study, it can be concluded that using 50% acetone extract of, erodium glycophyllum has high antibacterial activity against pathogenic Staphylococcus aureus. Hot Soxhlet extraction method is recommended as well as 96 well treys microtitre plate method. The MIC of tested Erodium glycobhyllum against Ttaphyllococcus aureus was 25 and 50 mg/ml, respectively. Peganum showed moderate response to Eoridium Micrococcus luteaus showed height moderate response to Erodium, However the exception of Erodium in high concentration, none of the tested plants showed any signs of toxicity in rats tested. The former produced liver fatty changes and haemorrhages in the kidneys.Toxicity experiments of Erodium glycophyllum, and Artimisa herba using experimental animals (rats) confirm the safety of such plants for therapy of various diseases. An antibacterial evolution for the total extract of tested medicinal plants could also reveal a more potent activity toward tested pathogenic Gram positive and Gram negative bacteria. However, the plants differed significantly in the activity towards tested pathogenic bacteria. The differences could be attributed to their structural nature.

Extraction of Artemisinin, an Active Antimalarial Phytopharmaceutical from Dried Leaves of Artemisia annua L., Using Microwaves and a Validated HPTLC-Visible Method for Its Quantitative Determination

A simple, rapid, precise, and accurate high-performance thin-layer chromatographic method coupled with visible densitometric detection of artemisinin is developed and validated. Samples of the dried Artemisia annua leaves were extracted via microwaves using different solvents. This method shows the advantage of shorter extraction time of artemisinin from leaves under the influence of electromagnetic radiations. Results obtained from microwave-assisted extraction (MAE) were compared with hot soxhlet extraction. Chromatographic separation of artemisinin from plant extract was performed over silica gel 60 F254 HPTLC plate using n-hexane : ethyl acetate as mobile phase in the ratio of 75 : 25, v/v. The plate was developed at room temperature 25 ± 2.0°C. Artemisinin separation over thin-layer plate was visualized after postchromatographic derivatization with anisaldehyde-sulphuric acid reagent. HPTLC plate was scanned in a CAMAG’s TLC scanner 3 at 540 nm. Artemisinin responses were found to be linear over a range of 400–2800 ng spot−1 with a correlation coefficient 0.99754. Limits of detection and quantification were 40 and 80 ng spot−1, respectively. The HPTLC method was validated in terms of system suitability, precision, accuracy, sensitivity (LOD and LOQ), and robustness. Additionally, calculation of plate efficiency and flow constant were included as components of validation. Extracts prepared from different parts of the plant (leaves, branches, main stem, and roots) were analyzed for artemisinin content, in which, artemisinin content was found higher in the leaf extract with respect to branches and main stem extracts; however, no artemisinin was detected in root extract. The developed HPTLC-visible method of artemisinin determination will be very useful for pharmaceutical industries, which are involved in monitoring of artemisinin content during different growth stages (in vitro and in vivo) of A. annua for qualitative and quantitative assessment of final produce prior to commercial-scale processing for assessment of cost-benefit ratio.

Anti-arthritic activity of Barleria prionitis Linn. leaves in acute and chronic models in Sprague Dawley rats

AimThe present investigation was designed to evaluate anti-arthritic potential of ethyl acetate fractions of chloroform extract from leaves of Barleria prionitis. Materials and methodsBarleria prionitis L. leaves were defatted by petroleum ether and then successive extraction was done with chloroform and methanol by the hot Soxhlet extraction method. Chloroform extract was further fractionated with solvent ethyl acetate to obtain EABP. This fraction was evaluated at two doses 125 and 250mg/kg, against formaldehyde-induced acute non immunological and Freund’s Complete Adjuvant-induced chronic immunological arthritis in rats. Arthritis assessment, paw volume, body weight, motor incoordination and nociceptive threshold were measured.Haematological assessments of red and white blood cells, erythrocyte sedimentation rate, as well as histopathological studies were also done on day 21, after animals were sacrificed. ResultsDose dependent and significant inhibition of oedema was observed in both acute as well as chronic models. The extract at dose 250mg/kg showed most potent and significant (P⩽0.05–0.01) paw oedema inhibition which is supported by the results of body weight, biochemical parameters, motor incoordination and nociceptive threshold in Freund’s Complete Adjuvant-induced arthritis model.Treatment with EABP also decreased the histopathological alterations induced by Freund’s Complete Adjuvant. ConclusionIn the present investigation, extract protects synovial membrane by improving the health status through haematinic parameters and exhibits promising anti-arthritic activity. This finding thus supports the traditional use of Barleria prionitis for rheumatism. However, further studies are needed to carry out the isolation of active constituents of the fraction responsible for the activity.

Anticonvulsant Effect of Cyperus rotundus Linn Rhizomes in Rats

Objective : To evaluate the anticonvulsant effect of Cyperus rotundus Linn rhizomes against maximal electroshock (MES) and pentylenetetrazole (PTZ) induced tonic seizers in albino rats. Materials and methods : Ethanol extract of Cyperus rotundus Linn rhizomes were obtained by continuous hot soxhlet extraction. The extract was assessed for anticonvulsant activity by measuring (sec) the duration of tonic flexion, tonic extensor, clonus, stupor and recovery phase in rats. Results : Phytochemical investigation of ethanol extract revealed the presence of flavonoids, vitamins and carbohydrates. The ethanol extract (100 mg / kg, p.o.) reduced hind limb extension and duration of convulsion significantly, (P < 0.001) which was comparable to standard drug phenytoin (25 mg / kg, i.p.) and diazepam (4 mg /kg, i.p.) respectively. Conclusion : The ethanol extract of Cyperus rotundus rhizomes is worthwhile to develop the potent phytoconstituent for treatment of epilepsy and the flavonoids present in ethanol extract could be attributed for anticonvulsant activity.

Polybrominated diphenyl ethers, polychlorinated biphenyls and organochlorine pesticides in sediment cores from the Western Scheldt river (Belgium): analytical aspects and depth profiles

A rapid and simple analytical method for the determination of organochlorines, such as polychlorinated biphenyls (PCBs) and selected organochlorinated pesticides (OCPs) and organobromines, such as polybrominated diphenyl ethers (PBDEs), in sediment samples was optimised using CRM 536 (PCBs in freshwater sediment). The method involved a hot Soxhlet extraction that reduced the extraction time to 2 h. Elemental sulphur, which is present in sediments and may interfere during the analysis, was removed by means of copper powder added to the sediment during extraction and into the clean-up cartridge. The analysis of PCBs and OCPs was accomplished by gas chromatography with electron capture or mass spectrometric detection. Similar quantitative results for PCB congeners in CRM 536 were obtained using a 50-m capillary column and a 10-m narrow bore column suited for fast analysis. The analysis of PBDEs was done by mass spectrometry in negative chemical ionisation mode. Concentrations of organic pollutants in two sediment cores (approximately 50 cm depth) from the Scheldt river (south of Antwerp, Belgium) showed a relative steady state for PCBs and DDTs, with a slight decrease in the top layers, suggesting a slight decline in their concentrations due to restrictions in their usage. On the contrary, PBDEs were showing an increase in their concentrations in the top layers (up to 270 and 8400 ng/g dry weight for sum of tri- to hexa-BDE congeners and for BDE 209, respectively). This suggests an increasing trend in the concentrations of PBDEs in the Belgian environment.

Persistent chlorinated pesticides and polychlorinated biphenyls in selected fish species from Lake Tanganyika, Burundi, Africa

Concentrations of selected organochlorine pesticides and PCBs in seven fish species (cichlids) from the north end of the Lake Tanganyika, Burundi, Africa were determined. Results were compared to previous work on the Lake Tanganyika and other water bodies and to the European Community maximum residue levels (MRLs) in edible fat. The analytical method included a hot Soxhlet extraction with a mixture of acetone: hexane (1:3, v/v), gravimetrically lipid determination, and a single step clean-up. For PCBs and stable pesticides, the clean-up was done on activated silica gel impregnated with concentrated sulfuric acid, while for non acid-stable pesticides superposed layers of alumina, silica and florisil impregnated with 15% methanolic solution of KOH were successively used. Recoveries of organochlorine pesticides from certified reference material (CRM 430) were ranging from 86% for p,p′-DDT to 107% for endrin, while recoveries from blank fat spiked fortified at three different levels were between 65% for alachlor at the lowest fortification level and 107% for mirex at the highest fortification level. The limits of detection for each analyte were ranging from 0.1 ng/g to 0.5 ng/g fat. All chlorinated pesticides were found in the analyzed species but at low concentrations. Boulengerochromis microlepis contained the highest concentrations of HCHs (288.2±15.5 ng/g fat) and DDTs (909.1±42.5 ng/g fat), while the highest PCB levels (166.7±37.4 ng/g fat for the sum of 12 congeners) were found in Oreochromis niloticus. However, there is no evidence that Lake Tanganyika is more contaminated with pesticides than other African water bodies.

Analysis of Polycyclic Aromatic Hydrocarbons in Sediments, Sewage Sludges and Composts from Municipal Refuse by H PLC

Abstract The extraction of 6 selected PAHs, Fluoranthene, Benzo(b)fluoranthene, Benzo(k)-fluoranthene, Benzo(a)pyrene, Benzo(ghi)perylene and Indeno(1, 2, 3-cd)perylene has been improved by hot soxhlet extraction with hexane/acetone. Overall concentrations for sediments (Neckar) lie between 4.6 and 21.8mg/kg (mean value 8.6 mg/kg). The corresponding values for the other substrates are waste water 129–2504 (791) ng/kg; sewage sludge 2.2–20.4 (9.7) mg/kg; municipal refuse 0.06–187 (6.9) mg/kg and waste compost 10.7–173.4 (14.7) mg/kg. It can therefore be concluded, that in all sinks of PAHs (sediments, sewage sludge and municipal refuse) the content is roughly the same. The PAH pattern of sediments and sewage sludges is very constant for different sampling sites. In contrast organic municipal waste shows marked pattern variations. For waste water treatment plants a positive correlation between daily water input and PAH content could be shown. PAH pattern comparison shows decreasing in-homogeneity from munic...