Diethyl Ether-soluble Fraction Research Articles

The pro-apoptotic activity of sinueracasbanone D isolated from Sinularia Leptoclados in hepatocellular carcinoma cells.

The soft-bodied corals of the genera Sarcophyton and Sinularia (Alcyoniidae) are known as a warehouse of casbane and cembranoid diterpenoids with remarkable antitumor effects. Two casbane-type diterpenoids (1, 2) along with four cembrane-type diterpenoids (3-6) were isolated from the diethyl ether soluble fraction of the organic extracts of the Red Sea soft corals Sinularia leptoclados and Sarcophyton glaucum, respectively. The antiproliferative activity of all isolated compounds (1-6) against three hepatocellular carcinoma cells, namely, Huh-7, SNU 499, and HepG2, along with the normal cells EA.hy 926, was evaluated. Sinueracabanone D (1) displayed a remarkable antiproliferative effect against the examined cancer cell lines, especially HepG2 cells with IC50 of 4.0 ± 0.37µM. Cell cycle analysis indicated compound 1 caused the accumulation of HepG2 cells in the G2/M-phase. Further, compound 1 exhibited significant pro-apoptotic activities in HepG2 cells as evidenced by annexin V staining, enhanced mRNA expression of Bax, cytochrome C, and caspase 3, as well as inhibition of Bcl2 expression. Also, challenging HepG2 cells with sinueracabanone D (1) enhanced the active oxygen species generation and decreased mitochondrial membrane potential. In conclusion, compound 1 possesses potent antiproliferative activities against HepG2 cells. These antiproliferative activities are mediated, at least partly, by their ability to induce apoptosis, mitochondrial dysfunction, and oxidative stress.

Liquid Chromatography-Mass Spectrometry Characterized Hydrolysate Fractions Possess Anticancer Activity In Vitro

To find new plant-derived antitumor drugs, hydrolysate and fractions of poplar were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for their inhibitory effect against liver cancer HepG-2 cells. Strong cytotoxicity of hydrolysate was revealed at processing temperature of 180 °C or above. The hydrolysate formed at 180 °C was sequentially extracted using organic solvent to obtain five fractions, and only the diethyl ether-soluble fraction (FDe) showed specific cytotoxicity. The eluted fraction of acetone/n-hexane (F1) was further isolated by column chromatography separation from the FDe fraction at a yield of 70%, and could severely decrease cell viability. LC-MS chromatography indicated that 5-hydroxymethyl furfural, ρ-hydroxybenzoic acid and syringaldehyde were the main compounds in the F1 fraction. Furthermore, the results of flow cytometry, Western blotting, and polymerase chain reaction indicated that syringaldehyde could tightly control the growth and metabolism of HepG-2 cells. The findings could move forward the value-added applications of lignocellulosic hydrolysate on traditional medicines.

Preparation of oligomeric dehydrogenation polymer and characterization of its antibacterial properties

To investigate the relationship between the chemical structural characteristics of lignin and its antibacterial activity, a low molecular weight dehydrogenation polymer (DHP) was synthesized in vitro with isoeugenol as a precursor and catalyzed by laccase. The DHP was fractionated to obtain a petroleum ether-soluble fraction (F1), diethyl ether-soluble fraction (F2), ethanol-soluble fraction (F3), and acetone-soluble fraction (F4). The results of antibacterial experiments showed that only F1 and F2 could effectively inhibit the growth of Escherichia coli and Staphylococcus aureus. Furthermore, nine compounds (Z1 to Z9) were obtained via the column chromatographic separation from F1 and F2. Mass spectrum analysis results showed that all of these compounds contained a β-5 structure. Antibacterial experiments showed that dimers (Z1 and Z2) could inhibit both S. aureus and E. coli. The trimers, tetramers, and pentamers (Z3 to Z9) could inhibit S. aureus but had no inhibitory effect on E. coli. The aldehyde groups and the condensed 5-5 structure, decreased the antibacterial properties of DHP, whereas the presence of the β-5 structure may be related to the antimicrobial ability of DHP.

Effect of debarking water from Norway spruce (Picea abies) on the growth of five species of wood-decaying fungi.

Norway spruce (Picea abies) debarking water is an aqueous extract obtained as waste from the debarking of logs at paper mills. The debarking water contains a mixture of natural compounds that can exhibit diverse biological activities, potentially including fungicidal activity on some species of wood-decaying fungi. Thus, we investigated the growth rates of such fungi on agar plates to which debarking water extracts had been added. The experiment included five wood-decaying fungi, viz. Gloeophyllum sepiarium, Oligoporus lateritius, Ischnoderma benzoinum, Junghuhnia luteoalba, and Phlebia sp. Growth reduction was observed for all species at the highest tested concentrations of freeze-dried and ethanol-extracted debarking water, the ethyl acetate-soluble fraction and the diethyl ether-soluble fraction. However, the magnitude of the effect varied between different species and strains of individual species. The brown-rot fungi G. sepiarium and O. lateritius were generally the most sensitive species, with the growth of all tested strains being completely inhibited by the ethyl acetate-soluble fraction. These results indicate that development of antifungal wood-protecting agents from debarking water could potentially be a way to make use of a low-value industrial waste.

Effect of Catalysts on Oxidation of Ruqigou Coal with NaOCl

The effect of molecular sieve, activated carbon, and nickel-based catalyst on oxidation of Ruqigou coal with NaOCl was investigated. The yields of diethyl ether-soluble fractions from reaction mixture are 67.3% for black test, 71.2% for molecular sieve, 68.6% for activated carbon and 70.3% for nickel-based catalyst, respectively. The results indicate that molecular sieve, nickel-based catalyst and activated carbon can all improve the oxidation reactivity of coal in aqueous NaOCl solution. Molecular sieve and nickel-based catalyst can convert most of the organic matters contained in coal into solvent-soluble species. The catalysis of molecular sieve is the highest, followed by nickel-based catalyst, activated carbon is relatively small.

Identification of a Xanthine Oxidase-inhibitory Component from Sophora Flavescens using NMR-based Metabolomics

We demonstrate that NMR-based metabolomics studies can be used to identify xanthine oxidase-inhibitory compounds in the diethyl ether soluble fraction prepared from a methanolic extract of Sophora flavescens. Loading plot analysis, accompanied by direct comparison of 1H NMR spectraexhibiting characteristic signals, identified compounds exhibiting inhibitory activity. NMR analysis indicated that these characteristic signals were attributed to flavanones such as sophoraflavanone G and kurarinone. Sophoraflavanone G showed inhibitory activity towards xanthine oxidase in an in vitro assay.

High-speed counter-current chromatography: an effective method for the isolation of flavonoids and profisetinidin from fustic (Cotinus coggygria Scop.)

While chromatographic methods such as column chromatography and semi-preparative HPLC are widely employed during purifications of plant extracts, high-speed counter-current chromatography (HSCCC) is only occasionally utilized. This method based on liquid-liquid partition is advantageous as it avoids the loss of analytes due to irreversible adsorption. The present research focuses on the analysis of the diethyl ether-soluble fraction of a crude extract from Cotinus coggygria (Anacardiaceae) wood. After preliminary separation through vacuum liquid chromatography over RP-18 material (solvent: acetonitrile/water gradient), two of the resulted fractions (A-3, CH3CN/H2O 10/90, v/v and A-8, CH3CN/H2O 36/64, v/v) were purified on Sephadex LH-20 (solvent: methanol), yielding enriched fractions; four thereof were selected for HSCCC separations. An optimized solvent system was developed, comprising a mixture of hexane, ethyl acetate, methanol and water (1/2.5/1/1; all v/v). For separations, a P.C. Inc. (Potomac, USA; HSCCC multilayer coil, series 690) instrument was used. The system was operated in the „tail to head“ mode, with the upper solvent layer as mobile phase. HSCCC using the above solvent system afforded the isolation of seven compounds: fustin (1), dihydroquercetagetin (2), epifisetinidol-(4β→8)-(+)-catechin (3), fisetin (4), quercetin (5), butein (6), and the new natural compound C-3/C-3“ dimer of 3′,4′,7-trihydroxyflavanone (7). Their structure was elucidated by 1D (1H NMR, 13C NMR) and 2D (HSQC, HMBC) NMR experiments. The here described HSCCC solvent system is suitable for the separation of medium-polarity phenolic compounds from C. coggygria wood.

8,14-Secopregnane glycosides from the aerial parts of Asclepias tuberosa

Twenty pregnane glycosides, tuberoside A 1–L 5, were isolated from the diethyl ether-soluble fraction of the MeOH extract from the aerial parts of Asclepias tuberosa (Asclepiadaceae). The pregnane glycosides were composed of 8,12;8,20-diepoxy-8,14-secopregnane as aglycon, and d-cymarose, d-oleandrose, d-digitoxose and/or d-glucose as the component sugars. Their structures were established using NMR spectroscopic analysis and chemical methodologies.

Chemical constituents from Gmelina arborea bark and their antioxidant activity

Gmelina arborea Roxb. is a fast-growing species and is known to have been used in traditional Indian medicine. Chemical constituents from the bark have not been reported, although some chemical constituents from part of this plant (heartwood, leaf, and root) are known. In this study, the bark meal was successively extracted with acetone and methanol. Fractionation of the acetone extract with n-hexane, diethyl ether, and ethyl acetate and subsequent chromatographic separation of the fractions led to the isolation of four compounds. The diethyl ether-soluble fraction yielded tyrosol [2-(4-hydroxyphenyl)ethanol] (1); (+)-balanophonin (2), an 8-5′ neolignan, with opposite optical rotation to known (−)-balanophonin; and gmelinol (3), a known lignan. The ethyl acetate-soluble fraction afforded a new phenylethanoid glycoside to the best of our knowledge, which was identified as (−)-p-hydroxyphenylethyl[5′″-O-(3,4-dimethoxycinnamoyl)-β-d-apiofuranosyl(1′" → 6′)]-β-d-glucopyranoside (4). From the methanol extract, two known compounds, 2,6-dimethoxy-p-benzoquinone (5) and 3,4,5-trimethoxyphenol (6), were isolated and identified. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay of the identifi ed compounds indicated that 3,4,5-trimethoxyphenol (6) exhibited moderate activity.

Hypoglycemic effect of Treculia africana Decne root bark in normal and alloxan-induced diabetic rats.

The solvent partitioned purified fractions of the hydro-acetone root bark extract of the African breadfruit (Treculia africana Decne) were evaluated for hypoglycemic activities in normal and diabetic albino rats. Fasting blood glucose levels were estimated by the use of a glucometer at pre-determined intervals after oral administration of the test extracts/fractions. Results revealed that the test fractions have only a slight effect on blood sugar level of normal rats. On short term and chronic administration in diabetic rats however, diethyl ether-soluble (DEF) and the water-soluble (WSF) fractions significantly reduced the fasting blood sugar levels (p<0.05) at differing rates when compared with the control group of animals. The diethyl ether soluble fraction (10 mg kg(-1) dose level) was found to exhibit the highest activity giving 69.4% reduction in blood sugar level (at 240 hours) which was in comparable range with the reference standard glibenclamide (0.5 mg kg(-1)) which reduced blood sugar levels by 65.8% below the initial baseline values.

A nontoxic antitumour compound from the leaves of Bauhinia scandens characterized as 1- O-alkyl glycerol by gas–liquid chromatography and evaluation of its antitumour property by Brine Shrimp bioassay

This is a report of extraction and identification of 1- O-alkyl glycerol present in the dried leaves of Bauhinia scandens. Fifty percent aqueous ethanolic extract of the plant at room temperature was fractionated over petroleum ether and diethyl ether. The diethyl ether soluble fraction showed positive bioactivity in Brine Shrimp bioassay. Isolation and purification of the active principle was subsequently done from diethyl ether fraction. The diethyl ether fraction was separated into acidic and neutral part. The acid free fraction was screened to be positive in Brine Shrimp bioassay. The NMR spectra (in CDCl 3) indicated the probability of its lipoidal nature. The total lipid fraction was resolved into neutral, glyco, and phospho-lipids by column chromatography. Only the neutral fraction showed positive response to Brine Shrimp toxicity test, out of which again a Brine Shrimp positive fraction was separated by thin layer chromatography and identified as 1- O-alkyl glycerol. This fraction was acetylated and GLC analysis of the 1- O-alkyl-2,3-diacetyl glycerol was done. Our results demonstrate that the work may be cited as a nonhazardous and nonchemical management of therapeutic importance.

Regulation effect of Phyllostachys pubescens methanol extractives on growth of seed plants

Methanol extractives from moso bamboo (Phyllostachys pubescens) culms were found to have some regulation effects on the growth of the seed plants tested. They showed inhibition or promotion of hypocotyl and radicle growth of lettuce, watercress, and chrysanthemum. The methanol extractives were fractionated with n-hexane, diethyl ether, and ethyl acetate. The diethyl ether-soluble fraction contained more phenolic substances than the other fractions and showed strong inhibition of growth in lettuce seeds. The water-soluble fraction showed a promotion effect on the hypocotyl growth of lettuce. The water-soluble fraction was heated at 200°C for 8h, and the inhibition effect on the radicle growth of lettuce decreased and the promotion effect on the hypocotyl growth increased at 0.1% concentration.

Antioxidant activity and components of Salvia plebeia R.Br. — a Chinese herb

The antioxidant properties of the extracts from Salvia plebeia R.Br. which was screened out of over 700 species of Chinese herbs, were tested in lard at 110°C using the Oxidative Stability Instrument. The ethyl acetate extract of the herb was re-extracted by solvents (with increasing polarity) into petroleum ether-, diethyl ether-, acetone-and-ethanol-soluble fractions. The fractions obtained were then separated according to their acidic properties. From the most active sub-fractions, namely the acidic sub-fraction of the petroleum ether-soluble fraction and the weakly acidic sub-fraction of the diethyl ether-soluble fraction, three antioxidant components were isolated and identified as royleanonic acid, hispidulin and eupatorin. The royleanonic acid was a novel compound and eupatorin was isolated for the first time from the herb. Though royleanonic acid and hispidulin prolonged the induction period significantly, their antioxidant activities were much weaker than the crude extracts, implying that synergistic effects might be responsible for the high activity of the crude extracts.

Evaluation of extracts from Gevuina avellana hulls as antioxidants.

The antioxidant activity of the extracts from Gevuina avellana hulls was evaluated and compared with that of BHT (butylated hydroxytoluene) and BHA (butylated hydroxyanisole), using the beta-carotene bleaching assay, the accelerated oxidation of crude soybean oil, and the 2,2-diphenyl-beta-picrylhydrazyl (DPPH) radical scavenging method. Solvents of different polarity were used to obtain the extracts. Both the extraction yield and the antioxidant activity were strongly dependent on the solvent. The ethanol and diethyl ether soluble fractions were the most active with the beta-carotene assay. Ethanol and methanol extracts were the most active in hydrogen radical scavenging activity. Water and methanol inhibited more efficiently the oxidation of soybean oil at 70 and 80 degrees C, respectively. As a general trend, increased antioxidant activity was observed for increased extract concentration. Except the acetone extracts, all were stable after 6 months storage at 4 degrees C. The ethanol solubles from G. avellana hulls present antioxidant activity similar to that of synthetic antioxidants and to other reported residual agroindustrial materials.

Ent-Isocopal-12-ene-15,16-dialdehyde fromSpongia officinalis

The X-ray analysis of the natural product ent-isocopal-12-ene-15,16-dialdehyde, 1,4,4a,4b,5,6,7,8,8a,9,10,10a-dodecahydro-4b,8,8,10a-tetramethyl-1,2-phenanthrene-dicarboxaldehyde, C 20 H 30 O 2 , is reported. The compound was isolated, together with other diterpenes of the spongian type, from the diethyl ether soluble fraction of Spongia officinalis [Cimino, Morrone & Sodano (1982). Tetrahedron Lett. 23, 4139-4142] and characterized. In the asymmetric unit, there are two molecules showing high geometrical and conformational similarity. The C-20 diterpenoid presents a trans-fused tricyclic system with a 1,4-dialdehyde function, adjacent to the double bond of the cyclohexene ring. Short intramolecular contacts, especially between the axial and isooriented methyl groups, cause significant distortions in the ring skeleton similar to that observed in other correlated structures. The profile of the molecule is rather bent (radius of curvature about 13 A) in the direction perpendicular to the averaged molecular plane. Similar bending has been observed in the correlated scalaradial and 12-deacetoxyscalaradial structures and helps to improve the intramolecular interactions.

Myricadiol and Other Taraxerenes fromScaevola spinescens

Scaevola spinescens R. Br. (Goodeniaceae), a West Australian semi-arid native plant, has been found to contain a number of pentacyclic triterpenoid compounds of the taraxerene type in high yield compared with other species in which these compounds are known to occur. Isolation of these molecules, which are potential lead compounds for synthetic anti-cancer drugs, was achieved by partitioning the diethyl ether-soluble fraction, of the methanol Soxhlet extract, between hexane and aqueous methanol, followed by base extraction of minor components from the methanol isolate and recrystallisation or column chromatography. The major component isolated from the extract, and main subject of this report, is the pentacyclic triterpenoid, 14-taraxerene-3,28-diol (1; myricadiol).

Steam-Explosion Lignins: Fractionation, Composition, Structure and Extractives

Abstract The acetone-soluble lignins of steam-exploded Pinus radiata and Eucalyptus regnans wood were fractionated by sequential extraction with the solvents hexane, diethyl ether, chloroform and acetone. For a given wood and SE process, the fractions showed differences in composition and in the structures of the lignin fragments present. Resin and fatty acid extractives make a significant contribution to the composition of P. radiata steam-explosion lignins. They can be partially removed by extraction with hexane, but a fraction may be bound to diethyl ether-soluble lignin fragments. Extractives make an insignificant contribution to the composition of E. regnans lignin. The effect of extractives on lignin properties and utilisation of these lignins is briefly discussed. The unfractionated lignin of this hardwood contains a negligible amount of extractives and it gives only a small diethyl ether-soluble fraction, comprised of low MW fragments with a high content of free phenolic hydroxy and α-CHO groups. ...

Extractive components responsible for the discoloration of Ilomba wood (Pycnanthus angolensis Exell)

The wood of Ilomba (Pycnanthus angolensis Exell) may seriously discolor in the log after felling and also in lumber during drying. The discoloration is associated with the occurrence of bacterial metabolites. The components responsible for the discoloration were extracted completely from the wood before discoloration with hot methanol and separating into petroleum ether, diethyl ether, ethyl acetate and water soluble and insoluble fractions. Bioassays using nutrient liquids inoculated with Pseudomonas fragi revealed that the diethyl ether soluble fraction discolored most. Chemical characterization of the individual components indicated that three different types of components could be involved which are the (−)-epicatechin and (+)-catechin, the intensely red compound and the water soluble component of the methanol extracts. Their contributions to the discoloration are discussed on the basis of their colorimetric characteristics and amounts present in the wood.

Biosynthesis, Deposition, and Partial Characterization of Potato Suberin Phenolics

Alkaline nitrobenzene oxidation of the polymeric materials from wound-healed potato (Solanum tuberosum L. var. White Rose) tuber tissue liberated p-hydroxybenzaldehyde, vanillin, and minor amounts of syringaldehyde as determined by gas chromatography/mass spectrometry. The aromatic aldehydes were derived only from periderm. The amounts of aromatic aldehydes liberated were used as a measure of the deposition of phenolic suberin components. Phenolic deposition began after about 2 days of wound healing; after 8 days the amounts of p-hydroxybenzaldehyde released by nitrobenzene oxidation leveled off at 5 milligrams per gram dry weight and after 12 days vanillin liberation reached a maximum at 7.5 milligrams per gram dry weight. The time course of deposition of the phenolic polymeric material is analogous to that reported for the deposition of the aliphatic components of suberin and therefore these results are consistent with the proposed structure of suberin. Experiments with radiolabeled l-phenylalanine and cinnamic acid indicated that exogenous phenylalanine was less efficient than cinnamic acid as a precursor of suberin phenolics. Nitrobenzene oxidation of radiolabeled suberin preparations gave three major labeled fractions: a diethyl ether-soluble fraction containing aromatic aldehydes ( approximately 20%), an ethyl acetate-soluble fraction containing unknown compounds ( approximately 15%), and a condensed phenolic fraction ( approximately 10%). Thin-layer and gas-liquid chromatographic analysis of the ether fraction showed that the major labeled components were vanillin and p-hydroxybenzaldehyde. The condensed tannin fraction revealed the presence of several labeled macromolecular phenolic fractions. Elution profiles of the condensed tannin fraction from tissues suberized for different periods of time were essentially identical, suggesting qualitative similarity of deposition and polymerization of suberin phenolics throughout the duration of wound healing. Chlorogenic acid accumulation in wound healing potato tuber discs was measured by high-performance liquid chromatography. The level of this compound reached 130 micrograms per disk after 11 days and did not decline even after the deposition of suberin ceased, revealing no precursor role for this acid in suberization.

Toxicity of benthic dinoflagellates found in coral reef-II. Toxicity of benthic dinoflagellates in Okinawa.

Nine species of benthic dinoflagellates isolated at Ishigaki Island, Okinawa, were grown unialgally. They were Prorocentrum lima, prorocentrum concavum, prorocentrum rhathymum, Amphidinium carteri, Amphidinium klebsii, Coolia monotis, Ostreopsis siamensis, Ostreposis ovata, and Gambierdiscus toxicus. The harvested cells were extracted with boiling methanol and the extracts were fractionated into diethyl ether soluble, 1-butanol soluble, and water soluble fractions. Each fraction was tested by mouse and fish assays and by blood cell hemolysis test. The extracts of P. lima, P. concavum, A. carteri, A. klebsii, O. siamensis, O. ovata, and G. toxicus were confirmed to show toxicity to mice. Hemolytic activity was recognized in all the species tested. Ichthyotoxicity was demonstrated by A. carteri, A. klebsii, and P. concavum, the last being the most potent. With the exception of the water soluble toxin of O. siamensis, all the toxins were found in either diethyl either diethyl ether soluble fraction or 1-butanol soluble fraction or in both.