Chloroform Methanol Research Articles

3-(Dicyanomethylidene)indan-1-one-Functionalized Calix[4]arene-Calix[4]pyrrole Hybrid: An Ion-Pair Sensor for Cesium Salts.

A chromogenic calix[4]arene-calix[4]pyrrole hybrid ion pair receptor bearing an indane substituent at a β-pyrrolic position has been prepared. On the basis of solution-phase UV-vis spectroscopic analysis and (1)H NMR spectroscopic studies carried out in 10% methanol in chloroform, receptor 1 is able to bind only cesium ion pairs (e.g., CsF, CsCl, and CsNO3) but not the constituent cesium cation (as its perchlorate salt) or the F(-), Cl(-), or NO3(-) anions (as the tetrabutylammonium salts). It thus displays rudimentary AND logic gate behavior. Receptor 1 shows a colorimetric response to cesium ion pairs under conditions of solid-liquid (nitrobenzene) and liquid-liquid (D2O-nitrobenzene-d5) extraction.

Synthesis and properties of manganese complexes of meso-tetraphenyltetrabenzoporphyrin

The coordination of meso-tetraphenyltetrabenzoporphyrin and metal exchange of its Cd(II) complex with manganese(II) chloride and acetate in DMF and a chloroform–methanol mixture have been studied by spectrophotometry. The Mn(III) chloride and acetate acido complexes formed in these reactions have been isolated and characterized. The dissolution of the synthesized complexes in DMF in the presence of solid KOH gives Mn(II) meso-tetraphenyltetrabenzoporphyrinate.

Bioprospecting for anti-Streptococcus mutans: The activity of 10% Sesbania grandiflora flower extract comparable to erythromycin

ObjectiveTo search an herbal material, capable of inhibiting plaque producing bacteria Streptococcus mutans. MethodsTwenty materials comprising 10 flowers and 10 rhizomes were extracted with 70% ethanol. Their activity was then examined at a concentration of 10% (w/v) against Streptococcus mutans in vitro on Mueller–Hinton media. Erythromycin (Oxoid, 20 μg disc) was used as a positive control. Meanwhile, to establish a fingerprint guide for authentication or quality control, the most potent material was further analyzed regarding its chemical constituents by means of reversed phase-high performance liquid chromatography (HPLC) and thin-layer chromatography (TLC). ResultsOf the tested samples, Sesbania grandiflora (S. grandiflora) flower and Costus speciosus rhizome extracts showed the most potent activity with inhibited zone diameters of 18.5 and 14.8 mm, respectively. On the other hand, other extract plants showed a diameter zone in the range of 0.5–10.6 mm or being inactive (diameter = 0 mm). The activity of S. grandiflora was comparable to that of erythromycin (diameter = 18.0 mm). The best separation was achieved on HPLC system with acetonitrile-water with a ratio of 2:8, and a flow rate at 0.5 mL/min. TLC, meanwhile, was featured on chloroform–methanol (8.5:1.5) as a mobile system. ConclusionsS. grandiflora flower is a promising material to be developed as the active ingredient of anti-plaque toothpaste as well as mouthwash solution. The developed HPLC and TLC system can be used for a further standard in its material authentication as well as for a fingerprinting of quality control during the manufacturing process.

Efficient Procedure for N-Glycan Analyses and Detection of EndoH-Like Activity in Human Tumor Specimens.

Although the importance of glycosylation has been thoroughly recognized in association with a number of biological processes, efficient assessments of glycans have been hampered by both the limited size of specimens and lengthy sample preparations, particularly in clinical settings. Here we report a simple preparative method for N-glycan analyses. It involves only short one-step chloroform-methanol extraction in presence or absence of water prior to PNGase F deglycosylation. The procedure was successfully applied to the investigation of N-glycans obtained from small numbers of in vitro cultured cancer cells (≤1 × 10(5)) and to tumor tissues, including patient biopsies of small size. MALDI-MS analysis confirmed the efficient release of all N-glycan types including complex forms with poly-N-acetyllactosamine chains. In addition, nonaqueous extraction of specimens from several established cancer cell lines, as well as patient tumor tissues, yielded high-mannose glycans with one GlcNAc moiety (Man3-9GlcNAc), strongly suggesting preservation of enzymatic activity analogous to Endo H enzyme. In summary, the method is both a step toward the practical use of glycan profiling and a way to detect Endo H-like activity in cancer specimens.

Simultaneous analysis of aliskiren and hydrochlorothiazide in pharmaceutical preparations and spiked human plasma by HPTLC

A simple, selective and precise method based on HPTLC has been developed for the simultaneous determination of aliskiren and hydrochlorothiazide in a fixed-dose tablet formulation and human plasma. The chromatography was performed on silica gel 60 GF254 plates, with a mobile phase consisting of methanol–chloroform (6:4, v/v). Densitometric analysis of the analytes was carried out at 225nm. Under optimized conditions, the Rf values were 0.26±0.02 and 0.71±0.02, and the resulting regression plots were linear (r2≥0.9997) in the concentration ranges of 1.00–10.0 and 0.10–1.00μgband−1 for aliskiren and hydrochlorothiazide. The limit of detection and limit of quantitation of the validated method were 0.206 and 0.624μgband−1 for aliskiren and 0.015 and 0.046μgband−1 for hydrochlorothiazide, respectively. The % expected content of aliskiren and hydrochlorothiazide in the commercial tablet formulation was 99.2% and 101.3%, respectively. For spiked plasma sample preparation, the analytes and nebivolol internal standard were extracted from 500μL of plasma sample by solid-phase extraction on LiChrosep® DVB-HL cartridges. The mean extraction recovery of aliskiren and hydrochlorothiazide from human plasma was 87.2% and 76.5%, respectively. In addition, the stability of the analytes in plasma was established under different storage conditions.

Synthesis and properties of bromine-substituted Co(II) tetraphenylporphyrinates

The interaction of bromine-substituted tetraphenylporphyrins with cobalt(II) acetate in a chloroform–methanol mixture yielding the corresponding cobalt(II) porphyrinates has been studied by means of spectrophotometry. Treatment of Co(II) porphyrinates with bromine in the same medium has afforded the Co(III) porphyrinates.

Chemical constituent and antioxidant activity of the husk of Chinese hickory

Chinese hickory (Carya cathayensis Sarg.) is a common and nutritious nut. Twenty-nine phenolic compounds, together with three quinones and three triterpenoids, were isolated from Chinese hickory husks. Their structures were determined by comprehensive spectroscopic methods. The total methanolic extract, chloroform and ethyl acetate fractions and all the isolated compounds were evaluated for antioxidant activity and neuroprotective effects on SH-SY5Y cells, as well as the effects on the expression of PPAR-γ in 3T3-L1 cells. Quercetin (10) and protocatechuic acid methyl ester (24) showed pronounced antioxidant activities in all of the different antioxidant assays and neuroprotective effect against H2O2-induced oxidative stress. Some of the flavonoids could significantly decrease the mRNA expression level of PPAR-γ by approximately 70%. The present study provided supplement information for the evaluation of antioxidant activity and health benefit of Chinese hickory.

A study on morphogenesis of roots of Panax stipuleanatus H.T.Tsai et K.M.Feng in vitro and preliminary determination of oleanolic acid in roots

Panax stipuleanatus H.T.Tsai et K.M.Feng which belongs to the genus Panax (Araliaceae family) is an valuable medicinal herbs in Vietnam and China. In the rhizome of Panax stipuleanatus H.T.Tsai et K.M.Feng contains many olean-type triterpenoid saponins, which can improve mental stamina and reduces risks of cancers in humans. Up to now, there is no research on the morphological changes in adventitious root formation from the rhizome of this species. In this study, the callus morphogenesis from the rhizome and the adventitious root morphogenesis from callus were analyzed. The rhizome segments 1-1.5 cm in diameter and 1 cm thick were cultured on MS medium supplemented 30 g/l sucrose, 6 g/l agar and 0.5 mg/l 2.4-D in dark. Callus formed on the surface of the rhizome after four weeks. The first cell divisions occurred in the first two weeks, in secondary cortex parenchyma cells and vascular cambium of the rhizome. 26-week-old callus with slow cell proliferation within the cluster and the long cells outside clusters were transferred to the induced medium supplemented with 0.5 mg/l 2.4-D and 0.1 mg/l TDZ within 6 weeks. The calli were more tight and formed many clusters. The adventitious roots formed 10 weeks after the transfer to MS medium supplemented with 0.5 mg/l NAA. Callus formed spherical structures called embryo-liked but only developed the root pole. Results of the thin layer chromatography using chloroform–methanol (9:1, v/v) showed the presence of oleanolic acid in extracts of adventitious roots fromed from callus-derived rhizomes of Panax stipuleanatus H.T.Tsai et K.M.Feng.

Liquid–Liquid Equilibria for Ternary Systems of Water + Methoxycyclopentane + Alcohol (Methanol, Ethanol, 1-Propanol, or 2-Propanol)

Liquid–liquid equilibria data were determined for four ternary systems of water + alcohol + methoxycyclopentane (CPME); the alcohols used were methanol, ethanol, 1-propanol, and 2-propanol. All measurements were performed at 298.15 K and atmospheric pressure. Binodal curves were experimentally determined using both the cloud-point method and tie lines. The reliability of the tie-line data were verified by the Hand and Othmer–Tobias plots. Distribution coefficients and separation factors were determined from the tie-line data. The universal quasichemical activity coefficient model was used to correlate the experimental data. Additionally, these water–alcohol–CPME systems were compared to the water–methanol–chloroform system as a green alternative for Bligh and Dyer lipid extraction.

Effects of starvation for 4–20 days on the neutral lipid and phospholipid content of Biomphalaria glabrata as determined by high performance thin layer chromatography-densitometry

ABSTRACTThe effects of 4, 7, 10, 14, and 20 days of starvation on the neutral and phospholipid levels of Biomphalaria glabrata were determined by high performance thin layer chromatography (HPTLC)-densitometry. Snails were maintained in artificial spring water in jars at 25 ± 1°C. The digestive gland–gonad complex was extracted with chloroform–methanol (2:1), and Analtech laned preadsorbent silica gel HPTLC plates were used with petroleum ether–diethyl ether–glacial acetic acid (80:20:1) mobile phase, phosphomolybdic acid detection reagent, and scanning at 610 nm for neutral lipid analysis, and chloroform–methanol–water (65:25:4.5) mobile phase, cupric sulfate–phosphoric acid reagent, and scanning at 370 nm for phospholipids. Significant differences were observed in the triacylglycerol and steryl ester levels in the starved versus the control snails.

Oil production by six microalgae: impact of flocculants and drying on oil recovery from the biomass

Oil production in batch photoautotrophic cultures of the following microalgae is reported: the freshwater microalgae Chlorella vulgaris, Choricystis minor, and Neochloris sp.; the marine microalgae Nannochloropsis salina and Cylindrotheca fusiformis; and C. vulgaris grown in a full-strength seawater medium. In all cases, the solvent extraction of lipids from freeze-dried biomass is compared with extraction from the fresh biomass paste. For all algae, the oils could be extracted equally effectively from freeze-dried samples and the paste samples (67–88 % moisture by weight). Moisture content determinations of the biomass using the freeze-drying method and the high-temperature oven drying were found to be equivalent for all algae. The biomass recovered by flocculation with metal salts (aluminum sulfate, ferric chloride) followed by centrifugation had a certain amount of the flocculant irreversibly bound to it. Washing failed to remove the adsorbed flocculants. For all algae, the adsorbed flocculants did not interfere with oil recovery by solvent extraction. The solvent system of chloroform–methanol–water proved highly effective for quantitative extraction of the lipids from all algae.

Phytochemical Screening and Insecticidal Activity of Three Extracts of Tapinanthus bangwensis (Engl. Krause) on Sitophilus zeamais (Maize Weevil)

In order to find alternative to synthetic pesticides, plants are increasingly used by farmers to protect stocks against crop pests. Thus, phytochemical and biological tests are performed on three organic extracts (cyclohexan, chloroform and methanol) of Tapinanthus bangwensis. The data were analyzed by the General Linear Model procedure using the software Minitab 16. These results showed that the methanol extract gives a better insecticidal activity on Sitophilus zeamais. RIZA software was used to calculate the LC50 of each extract. The cyclohexane extract gives an LC50 of 2.66 mg/ml after 18 days of treatment, while the chloroform extract and methanol respectively give LC50 of 4.49 mg/ml and 6.99 mg/ml after 19 and 20 days of treatment.

Comparative study of membrane-stabilizing activities of kolaviron Dryopteris filix-mas and Ocimum gratissimum extracts

Background Diseases associated with inflammation have been one of the major concerns in medicine. Some anti-inflammatory drugs such as aspirin have been found to exert side effects on the gastrointestinal tract. Therefore, it is necessary to seek new chemotherapy agents from plant sources with little or no side effects that are capable of preventing inflammation-related disorders. Aim This study aims to investigate the effects of methanol extracts, aqueous and chloroform fractions of Dryopteris filix-mas (DF), Ocimum gratissimum (OG) leaves and kolaviron on membrane stabilization; acetyl salicylic acid was used as a reference drug. Materials and methods Whole blood of rats weighing 150–200 g was assessed using hypotonic solution-induced haemolysis of albino rats, which was determined spectrophotometrically. Results Of the three extracts, kolaviron showed the highest haemolysis inhibition capacity (49.6, 56 and 66.56%) in a concentration-dependent manner (2, 4 and 6 mg/ml, respectively) compared with acetyl salicylic acid, with a haemolysis inhibition capacity of 61.45, 67.22 and 70% in the order of increasing concentrations. This was followed by the aqueous fraction of OG leaves at 6 mg/ml, with percentage haemolysis inhibition of 61.1%, whereas the aqueous fraction of DF was 56.49% at 6 mg/ml. Conclusion The above result suggested that kolaviron, aqueous fractions of OG and DF could serve as excellent alternative anti-inflammatory therapy agents.

A validated high-performance thin-layer chromatographic method for the quantitation of protodioscin inTrigonella foenum-graecumand its herbal formulations

A simple, rapid, and sensitive high-performance thin-layer chromatographic (HPTLC) method was developed for the estimation of protodioscin from Trigonella foenum-graecum. Chromatographic separation was achieved on aluminum plates precoated with silica gel G60 F254 as the stationary phase and chloroform–methanol–glacial acetic acid (6.5:3.0:0.5 v/v) as the mobile phase. Densitometric evaluation was carried out at 515 nm after derivatizing the spots with p-dimethyl aminobenzaldehyde. The RF value of the protodioscin was found to be 0.31 ± 0.02. The response in terms of peak area was found to be linear over the concentration range from 400 to 1400 ng spot−1 with a regression coefficient of 0.9981 and mean recovery of 100.90 ± 3.00%. The developed method was validated as per the International Conference on Harmonization (ICH) guidelines. The limit of detection and limit of quantitation were found to be 100 ng spot−1 and 400 ng spot−1, respectively. Robustness of the developed method was assessed using experim...

Bioactive constituents of wood rot extract of tea, Camellia sinensis L.O. Kuntze against alates of low country live wood termite Glyptotermes dilatatus Bugnion and Popoff (Isoptera: Kalotermitidae).

Low country live wood termite (LCLWT), Glyptotermes dilatatus is attractive to rotted stumps of tea plant, Camellia sinensis. Rotted stumps are formed due to the attack of wood rot fungi in pruned stems. The objective of the present study was to investigate the response of LCLWT to extracts of rotted and healthy stems of susceptible tea cultivars, TRI 2023 and TRI 4042 and tolerant cultivars, TRI 2027 and TRI 4049 and isolate the LCLWT attractive fractions of tea stem extract. Since pieces of rotted stem of both susceptible and tolerant tea cultivars were more attractive to the alates than that of healthy stems, effects of EtOAc extracts of rotted and healthy stems of four tea cultivars were compared on behavior of the alates. The results revealed that the alates positively responded to extracts of rotted tea stems of four tea cultivars than that of healthy tea stems. Therefore hexane, chloroform and aqueous methanol fractions of the extracts of rotted stems were tested against alates using orientation bioassays. Results revealed that the hexane fraction of rotted stem of each cultivar was more attractive than that of the chloroform and methanol fractions. The results of bioassay guided fractionation of the hexane fraction using column chromatography revealed the presence of two bioactive sub-fractions suggesting non-polar compounds in rotted tea wood are more attractive to G. dilatatus than other sub-fractions. These two fractions can be used to develop a trapping mechanism to strengthen present IPM program of LCLWT.

Evaluation of different solvent mixtures in esterifiable lipids extraction from microalgae Botryococcus braunii for biodiesel production

Non-polar and polar solvents as well as their mixtures were tested for the extraction of microalgae lipids and thus, to evaluate their effect on total and esterifiable lipids extraction yields with potential to be converted to biodiesel. The obtained results show an increase in lipids and esterifiable lipids extraction yields when non-polar and polar solvent mixtures were used. The higher esterifiable lipids extraction yield was 19.2%wt (based on dry biomass) using a chloroform–methanol mixture (75%v/v of methanol), corresponding to a 98.9%wt esterifiable lipids extraction. In addition, esterifiable lipids extraction yield of 18.9%wt (based on dry biomass) was obtained when a petroleum ether–methanol mixture (75%v/v of methanol) was used, corresponding to a 96.9%wt esterifiable lipids extraction.

Determination of 11 Cannabinoids in Biomass and Extracts of Different Varieties of Cannabis Using High-Performance Liquid Chromatography.

An HPLC single-laboratory validation was performed for the detection and quantification of the 11 major cannabinoids in most cannabis varieties, namely, cannabidiolic acid (CBDA), cannabigerolic acid (CBGA), cannabigerol (CBG), cannabidiol (CBD), tetrahydrocannabivarin (THCV), cannabinol (CBN), Δ9-trans-tetrahydrocannabinol (Δ9-THC), Δ8-trans-tetrahydrocannabinol (Δ8-THC), cannabicyclol (CBL), cannabichromene (CBC), and Δ9-tetrahydrocannabinolic acid-A (THCAA). The analysis was carried out on the biomass and extracts of these varieties. Methanol-chloroform (9:1, v/v) was used for extraction, 4-androstene-3,17-dione was used as the internal standard, and separation was achieved in 22.2 min on a C18 column using a two- step gradient elution. The method was validated for the 11 cannabinoids. The concentration-response relationship of the method indicated a linear relationship between the concentration and peak area with r2 values of >0.99 for all 11 cannabinoids. Method accuracy was determined through a spike study, and recovery ranged from 89.7 to 105.5% with an RSD of 0.19 to 6.32% for CBDA, CBD, THCV, CBN, Δ9-THC, CBL, CBC, and THCAA; recovery was 84.7, 84.2, and 67.7% for the minor constituents, CBGA, CBG, and Δ8-THC, respectively, with an RSD of 2.58 to 4.96%. The validated method is simple, sensitive, and reproducible and is therefore suitable for the detection and quantification of these cannabinoids in different types of cannabis plant materials.

Lipid extraction techniques for stable isotope analysis of bird eggs: Chloroform–methanol leads to more enriched 13C values than extraction via petroleum ether

Stable isotope analysis is often used to determine dietary origin in ecological studies. Lipids are depleted in 13C compared with protein and, so, variation in lipid content can confound interpretations of diet. To avoid this issue, lipids can be extracted from samples prior to stable isotope analysis. The most common solvent used for lipid extraction, chloroform–methanol, is toxic and cannot be used in some laboratories. Here, the use of chloroform–methanol as a solvent was compared with an alternative method that uses petroleum ether as a solvent (N=32 eggs from seven species). The δ13C values using both methods were highly correlated (R2=0.99) but values derived from samples that were lipid-extracted using chloroform–methanol were enriched in 13C by 0.90±0.07‰ compared with samples that were lipid-extracted using petroleum ether. The C:N ratio was 3.60±0.02 (s.e.) for chloroform–methanol and 4.25±0.03 for petroleum ether implying that chloroform–methanol (which is more polar) more completely extracted lipids than petroleum ether. Furthermore, δ15N values derived from samples that were lipid-extracted using chloroform–methanol were enriched in 15N by 0.41±0.05‰ compared with samples that were lipid-extracted using petroleum ether. In conclusion, lipid extraction by chloroform–methanol more thoroughly removes lipids than lipid extraction by petroleum ether and consequently δ13C is higher after lipid extraction by chloroform–methanol than after lipid extraction by petroleum ether. An algebraic correction formula for each method is provided.

Changes in minimally processed apple tissue with storage time and temperature: mechanical–acoustic analysis and rheological investigation

Texture and mesostructure of packaged fresh-cut ‘Fuji’ apple slices were studied during 30 days storage at 4, 10 and 20 °C. Instrumental mechanical–acoustic texture evaluations were carried out, and cell wall materials were isolated from the flesh tissue by means of an ethanol and methanol–chloroform solvents extraction procedure. The emphasis was on relating the macroscopic loss of fresh texture characteristics to the changes in the rheological properties occurring to the structuring elements of the cell wall materials (CWMs). The rheology of the reconstituted CWM water dispersion was evaluated by means of oscillatory dynamic testing, and viscoelastic data were interpreted according to the ‘weak-gel model’ theory. The dynamics of the flowing components at the mesoscale structural level was related to the texture softening, which yields decrease in firmness and rigidity parameters, and an attenuation of the acoustic emission (fewer acoustic peaks and lower sound pressure level), as it was measured in the combined acoustic–mechanical test. The kinetic reaction rate values are presented. Softening of apple flesh is accompanied by slight cleavage of molecular assemblies and a loss in cell adhesion, mediated by the increase in assemblies’ water uptake. The ability to handle the relationship between the sounds produced during flesh crushing and the structure of the cellular tissue would assist breeders and geneticists in the selection and control of the apple crispness, or would support technologists in preventing postharvest softening during storage and retail.

Bioactivity of Cicuta virosa L. var. latisecta Celak. (Umbelliferae: Cicutal) against Red Imported Fire Ant under Laboratory and Field Conditions

We evaluated the bioactivities of compounds from Cicuta virosa L. var. latisecta Celak. against red imported fire ants (Solenopsis invicta Buren) under field and laboratory conditions. The compounds were as follows: methanol extract; petroleum ether, chloroform, and ethyl acetate fractions from the methanol extract; and the active compound isoimperatorin, which was isolated from the chloroform-fraction. The 7 d LC50 values of the methanol extract, petroleum ether, chloroform, and ethyl acetate fractions and isoimperatorin toward micrergates were 111.20, 214.45, 40.90, 569.67, and 25.73 mg/kg, res­pectively. The corresponding LC50 values toward macrergates were 155.78, 308.38, 75.01, 776.75, and 42.77 mg/kg, res­pectively. Under field conditions, baits containing 0.2% methanol extract, 0.1% chloroform fraction, and 0.05% isoimperatorin efficiently controlled S. invicta, with effectiveness percentages of 95.56%, 97.78%, and 95.56%, respectively on the 30th day after bait application. Such effectiveness percentages were not significantly different from that obtained using the positive control fipronil. The present study showed that C. virosa L. var. latisecta has potential as a natural control agent for the red imported fire ants.