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Orchids are rich treasure troves of various important phytomolecules. Among the various medicinal orchids, Ansellia africana stands out prominently in the preparing of various herbal medicines due to its high therapeutic importance. The nodal explants of A. africana were sampled from asymbiotically germinated seedlings on basal Murashige and Skoog (MS) medium and were micropropagated in MS medium supplemented with 3% sucrose and 10 µM meta topolin ( m T) + 5 µM naphthalene acetic acid (NAA) +15 µM indole butyric acid (IBA) + 30 µM phloroglucinol (PG). In the present study, the essential oil was extracted by hydrodistillation and the oleoresins by the solvent extraction method from the micropropagated A. africana . The essential oil and the oleoresins were analysed by Gas Chromatography (GC) and GC/MS (Mass spectrometry). A total of 84 compounds were identified. The most predominant components among them were linoleic acid (18.42%), l -ascorbyl 2,6-dipalmitate (11.50%), linolenic acid (10.98%) and p -cresol (9.99%) in the essential oil; and eicosane (26.34%), n-butyl acetate (21.13%), heptadecane (16.48%) and 2-pentanone, 4-hydroxy-4-methyl (11.13%) were detected in the acetone extract; heptadecane (9.40%), heneicosane (9.45%), eicosane (6.40%), n-butyl acetate (14.34%) and styrene (22.20%) were identified and quantified in the ethyl acetate extract. The cytotoxic activity of essential oil and oleoresins of micropropagated A. africana was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromide) assay on Vero cells compared to the standard drug doxorubicin chloride. The present research contains primary information about the therapeutic utility of the essential oil and oleoresins of A. africana with a promising future research potential of qualitative and quantitative improvement through synchronised use of biotechnological techniques.

Two new chlorinated secondary metabolites, saccharochlorines A and B (1 and 2), were isolated from the saline cultivation of a marine-derived bacterium Saccharomonospora sp. (KCTC-19160). The chemical structures of the saccharochlorines were elucidated by 2D NMR and MS spectroscopic data. Saccharochlorines A and B (1 and 2) exhibit weak inhibition of β-secretase (BACE1) in biochemical inhibitory assay, but they induced the release of Aβ (1-40) and Aβ (1-42) in H4-APP neuroglial cells. This discrepancy might be derived from the differences between the cellular and sub-cellular environments or the epigenetic stimulation of BACE1 expression., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Recently, growing interest is devoted to investigation of bioactive secondary metabolites of endophytic fungi. Thus, as an extension to our previous achievements related to antimicrobial potential of endophytic fungi, Phomopsis species isolated from conifer needles was selected as appropriately promising natural source for drug discovery. Its dichloromethane and ethanol extracts considerably inhibited growth of Escherichia coli and Staphylococcus aureus. Moreover, the individual compounds of dichloromethane extract have been separated, collected and purified using semi preparative liquid chromatographic analysis and comprehensively characterized using mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). Based on their antimicrobial activity and unique structural characteristics in comparison with well-established drugs from the same therapeutic category, two dominant compounds (Z)-(Z)-2-acetoxyprop-1-en-1-yl-3-(3-((E)-3,4-dihydroxypent-1-en-1-yl)oxiran-2-yl)acrylate (denoted as 325-3) and (Z)-(Z)-2-acetoxyprop-1-en-1-yl 3-(3-((E)-4-hydroxy-3-oxopent-1-en-1-yl)oxiran-2-yl)acrylate (denoted as 325-5) were recognized as valuable leading structures for future discovery of novel antibiotics.

The endophytic Trichoderma atroviridae UB-LMA was isolated as a symbiont of Taxus baccata and analyzed for its antimicrobial activity. By applying an original approach consisting of solid-state cultivation coupled with solid-phase extraction, a new methyl (R,E)-3-(1-hydroxy-4-oxocyclopent-2-en-1-yl)-acrylate derivative named EA-2801 (1) was isolated together with the previously reported isonitrin A and dermadin methyl ester. The chemical structure of 1 was determined by NMR and MS. Compound 1 showed antimicrobial activity against a panel of Gram-positive and -negative bacteria.

Three new pigment compounds--terreusinone A (1), pinophilin C (2) and cryptosporioptide A (3)-were isolated from a solid culture of Cordyceps gracilioides. The structures of these compounds were determined by extensive spectroscopic analysis including HRESIMS, 1D- and 2D-NMR. The structure of terreusinone A (1) was further confirmed by single-crystal X-ray crystallographic diffraction analysis. In an in vitro activity assay, 1, 2 and 3 exhibited high inhibitory activity against PTP1B, SHP2, CDC25B, LAR and SHP1. Terreusinone A (1) inhibited PTP1B, SHP2, CDC25B, LAR and SHP1 enzyme with IC50 values 12.5, >50, 4.1, 10.6, 5.6 µg/mL, respectively; pinophilin C (2) with IC50 values 6.8, 8.0, 4.5, 4.7, 3.4 µg/mL, respectively; and cryptosporioptide A (3) with IC50 values 7.3, 5.7, 7.6, >50, 4.9 µg/mL, respectively.

Ten secondary metabolites (1-10) including a new phenolic enamide, methyl (Z)-3-(3,4-dihydroxyphenyl)-2-formamidoacrylate (1), and a new meroterpenoid, 15-hydroxydecaturin A (2), were characterized from the EtOAc extracts of the marine alga-derived endophytic fungus Penicillium oxalicum EN-290. The structures of these compounds were elucidated on the basis of 1D and 2D NMR experiments and the absolute configuration of compound 2 was confirmed by electronic circular dichroism quantum calculations. Compound 1 showed potent activity against Staphylococcus aureus with an MIC value of 2.0 μg/ml, which is stronger than that of the positive control (chloromycetin, with an MIC 4.0 μg/ml). This compound also showed activity against harmful algal bloom causative species Nitzschia closterium with inhibition zones of 20, 16, and 10 mm at 20, 10, and 5 mg/ml, respectively. Interestingly, so far, this type of anti-HAB metabolites has only been found in the algal-derived isolate of P. oxalicum. It could probably be a defense of this fungus against environmental stress and threat of survival.

1-O-cis-Cinnamoyl-β-D-glucopyranose is one of the most potent allelochemicals that has been isolated from Spiraea thunbergii Sieb by Hiradate et al. It derives its strong inhibitory activity from cis-cinnamic acid (cis-CA), which is crucial for phytotoxicity. By preparing and assaying a series of cis-CA analogues, it was previously found that the key features of cis-CA for lettuce root growth inhibition are a phenyl ring, cis-configuration of the alkene moiety, and carboxylic acid. On the basis of a structure-activity relationship study, the substituent effects on the aromatic ring of cis-CA were examined by systematic synthesis and the lettuce root growth inhibition assay of a series of cis-CA analogues having substituents on the aromatic ring. While ortho- and para-substituted analogues exhibited low potency in most cases, meta-substitution was not critical for potency, and analogues having a hydrophobic and sterically small substituent were more likely to be potent. Finally, several cis-CA analogues were found to be more potent root growth inhibitors than cis-CA., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Ethnopharmacological Relevance: Onopordon acanthium (also known as Scotch thistle) is a medicinal plant of the Asteraceae family that is widely distributed in Europe and Asia. This plant has been long used in traditional medicine as a hypotensive, cardiotonic and diuretic agent., Aim of the Study: The present study is designed to isolate an active compound with ACE inhibition activity from O. acanthium, measure antioxidant activity, predict domain specificity and pharmacokinetic properties of the isolated compound., Materials and Methods: Methanolic extract of O. acanthium seeds, has been subjected to a repeated column chromatography to give a pure compound with Angiotensin Converting Enzyme (ACE) inhibition activity. The ACE inhibition activity was determined using hippuryl-L-histidyl-L-leucine (HHL) as substrate in an in vitro ACE assay. Structure of the pure compound, isolated from O. acanthium has been established by spectroscopic methods, including Infrared (IR), Nuclear Magnetic Resonance (NMR) and Mass spectrum analysis. In addition, antioxidant activity of the new isolated compound, was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and compared with those of BHT and Trolox as positive controls. Enzyme type inhibition and ACE-C or N domain specificity of the new compound was further evaluated through molecular modeling and docking studies., Results: Structure of the pure compound, isolated from O. acanthium (83±1% ACE inhibition activity at concentration of 330 μg/ml), has been established. The isolated compound possessed acceptable antioxidant activity (IC50 value of 2.6±0.04 μg/ml) in comparison with BHT (IC50 value of 10.3±0.15 μg/ml) and Trolox (IC50 value of 3.2±0.06 μg/ml). Molecular docking predicted competitive type enzyme inhibition and approximately similar affinity of the isolated compound for ACE-C and N domains., Conclusion: The results derived from computational and in vitro experiments, confirm the potential of the isolated compound, from O. acanthium as a new antihypertensive compound and give additional scientific support to an anecdotal use of O. acanthium in traditional medicine to treat cardiovascular disease such as hypertension., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

A multi-stage microaerobic biological fluidized bed reactor was used for the pretreatment of synthetic wastewater containing high concentration of acrylic acid (AA). The effect of influent load was investigated and the intermediate products of acrylic acid degradation were analyzed. It indicated that the removal rate of AA was above 95% with effluent acrylic acid less than 150 mg x L(-1) and COD removal rate of 15%-30%, under the following conditions: hydraulic retention time of 12 h, waste water temperature of 25 degrees C, influent acrylic acid concentration of 3 000-9 000 mg x L(-1), volume load of 6.0-18.0 kg x (m3 x d)(-1). The main intermediate products of acrylic acid degradation were acetic and propionic acids. The multi-stage microaerobic biological fluidized bed reactor can transform each 1.00 mol acrylic acid into 0.22 mol acetic acid and 0.36 mol propionic acid, and achieve the pretreatment of acrylic acid wastewater at high loads.

This study investigates the effect of introducing alkyl chain fluorination on the properties of polyacrylate nanoparticles prepared in aqueous solution by emulsion polymerization. For this, 2,2,3,3,4,4,4-heptafluorobutyl acrylate (1) and methyl trifluoroacrylate (2) were tested as monomers as a means to prepare fluorinated polyacrylate nanoparticles to evaluate how side chain fluorination may affect nanoparticle size and drug carrier properties. Our results show that as fluorine content within the polyacrylate matrix increases, the size of the nanoparticle systematically diminishes, from 45 nm (for nanoparticles containing no fluoroacrylate) to ~7 nm (for nanoparticles constructed solely of fluoroacrylate). We also observe that as fluoroacrylate content and hydrophobicity increases, the nanoparticles decrease their ability to incorporate lipophilic molecules during the process of emulsification. These findings have meaningful implications in the implementation of fluorinated nanoparticles in molecular delivery., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Gas-phase perfluoroalkyl carboxylic acids (PFCAs) sorb strongly on filter material (i.e., GFF, QFF) used in conventional high volume air samplers, which results in an overestimation of the particle-phase concentration. In this study, we investigated an improved technique for measuring the gas-particle partitioning of per- and polyfluoroalkyl substances (PFASs) using an annular diffusion denuder sampler. Samples were analyzed for 7 PFAS classes [i.e., PFCAs, perfluoroalkane sulfonic acids (PFSAs), fluorotelomer alcohols (FTOHs), fluorotelomer methacrylates (FTMACs), fluorotelomer acrylates (FTACs), perfluorooctane sulfonamides (FOSAs), and perfluorooctane sulfonamidoethanols (FOSEs)]. The measured particulate associated fraction (Φ') using the diffusion denuder sampler generally followed the trend FTACs (0%) < FTOHs (~8%) < FOSAs (~21%) < PFSAs (~29%) < FOSEs (~66%), whereas the Φ' of the C(8)-C(18) PFCAs increased with carbon chain length, and ranged from 6% to 100%. The ionizability of some PFASs, when associated with particles, is an important consideration when calculating the gas-particle partitioning coefficient as both ionic and neutral forms can be present in the particles. Here we differentiate between a gas-particle partitioning coefficient for neutral species, K(p), and one that accounts for both ionic and neutral species of a compound, K(p)'. The measured K(p)' for PFSAs and PFCAs was 4-5 log units higher compared to the interpolated K(p) for the neutral form only. The measured K(p)' can be corrected (to apply to the neutral form only) with knowledge of the pK(a) of the chemical and the pH of the condensed medium ("wet" particle or aqueous aerosol). The denuder-based sampling of PFASs has yielded a robust data set that demonstrates the importance of atmospheric pH and chemical pK(a) values in determining gas-particle partitioning of PFASs.

High-concentration acrylate wastewater was treated by an electrocatalytic reduction process. The effects of the cation exchange membrane (CEM) and cathode materials on acrylate reduction were investigated. It indicated that the acrylate could be reduced to propionate acid efficiently by the electrocatalytic reduction process. The addition of CEM to separator with the cathode and anode could significantly improve current efficiency. The cathode materials had significant effect on the reduction of acrylate. The current efficiency by Pd/Nickel foam, was greater than 90%, while those by nickel foam, the carbon fibers and the stainless steel decreased successively. Toxicity of the wastewater decreased considerably and methane production rate in the biochemical methane potential (BMP) test increased greatly after the electrocatalytic reduction process.

A theory-based approach is presented for the development of thermal field-flow fractionation (ThFFF) of polyacrylates. The use of ThFFF for polymer analysis has been limited by an incomplete understanding of the thermal diffusion which plays an important role in retention and separation. Hence, a tedious trial-and-error approach to method development has been the normal practice when analyzing new materials. In this work, thermal diffusion theories based on temperature dependent osmotic pressure gradient and polymer-solvent interaction parameters were used to estimate thermal diffusion coefficients (D(T)) and retention times (t(r)) for different polymer-solvent pairs. These calculations identified methyl ethyl ketone as a solvent that would cause significant retention of poly(n-butyl acrylate) (PBA) and poly(methyl acrylate) (PMA). Experiments confirmed retention of these two polymers that have not been previously analyzed by ThFFF. Theoretical and experimental D(T)s and t(r)s for PBA, PMA, and polystyrene in different solvents agreed to within 20% and demonstrate the feasibility of this theory-based approach., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The research was focus on the influence of experimental conditions to the removal efficiency of contaminant and the change of biodegradability in the treatment of acrylic fiber polymerization wastewater using three-dimensional electrode reactor with granular activated carbon. The anode was Ti/SnO2-Sb2O3 expanded metal sheet electrode. The cathode was Ti expanded metal sheet electrode. The parameters investigated were the reaction time, electrolytic voltage, initial pH value and aeration amount. The results show that the electrolytic voltage and initial pH value had greater impact on the removal efficiency of organic pollutants. Under the optimal experimental condition with electrolytic voltage 15 V, initial pH value 3, aeration amount 400 mL/min, the removal rates of COD, TOC and acrylonitrile were 32.59%, 22.17% and 89.70%, respectively,and the value of BOD5/COD increased from 0.02 to 0.42 within 120 min, which improved the biodegradability greatly and was beneficial for further biological treatment.

The butyl-acrylate-production wastewater was treated by a three-phase biological fluidized bed reactor. The influences of acrylic acid concentrations, p-toluenesulfonic acid concentrations, volumic load and hydraulic retention time on pollutants removal efficiencies were investigated. It was indicated that the reactor was suitable for the treatment of butyl-acrylate-production wastewater at a high loading rate. Acrylic acid of 100 mg/L or p-toluenesulfonic acid of 50 mg/L in the influent can inhibit the unacclimated microorganisms in the fluidized bed reactor. The inhibition effects were eliminated after an acclimation of two weeks. Acrylic acid and p-toluenesulfonic acid could be removed completely at COD loading rates up to 11.56-13.56 kg/(m3 x d). The effluent COD could satisfy the demand of Class II in Chinese Integrated Wastewater Discharge Standard (GB 8978-1996) at COD loading rates up to 8.86 kg/(m3 x d) when influent COD concentration is below 2000 mg/L. When the influent COD concentration was increased to 9550-11,800 mg/L(acrylic acid of 6244 mg/L and p-toluenesulfonic acid of 1000 mg/L), the effluent COD was 271-360 mg/L, which satisfied the demand of Class III in Chinese Integrated Wastewater Discharge Standard (GB 8978-1996) at COD loading rates of 7.96-9.83 kg/(m3 x d).

The solid-phase microextraction (SPME) technique was applied and optimized for collection of volatile compounds emitted from oestrous urine of mares Equs cabalus L. (Perissodactyla, Equidae) for GC-MS analyses. Variables such as type of SPME fibre, collection time of volatiles, and addition of salt were optimized to improve the sampling efficiency in two aspects: extent and selectivity of absorption/adsorption of urine volatiles onto SPME fibres. The data revealed that the number of volatiles and the total amount represented as quantitative peak areas of the compounds trapped on fibres coated either with polydimethylsiloxane-divinylbenzene or with divinylbenzene-carboxen-polydimethylsiloxane were significantly higher compared to those coated with polydimethylsiloxane, polyacrylate, and carbowax-divinylbenzene. The polydimethylsiloxane-divinylbenzene-type of fibre coating was chosen for optimization of sampling time and effect of salt addition. Sampling periods lasted for 15, 30, 60, 120, and 240 min. The optimal collection time of volatiles from urine maintained at about 36 degrees C was 60 min, as the number of compounds detected with amounts sufficient for quantification did not differ significantly from those trapped during longer collection periods. No significant increase in total amount of volatiles trapped was registered after 120 min of sampling. Addition of 0.3 g NaCl to the 2-ml of samples shortened the collection period from 60 to 15 min during which almost all compounds were trapped. Addition of salt has a significant effect at all sampling periods taking into consideration the total amounts of volatiles trapped. The total intensities increased about 8, 5, 3, 3, and 2 times at collection periods of 15, 30, 60, 120, and 240 min, respectively, when compare with the ones obtained from the urine samples with no salt addition. In oestrous mare's urine, 139 +/- 4 (average number +/- standard deviation) volatile compounds suitable for quantitative analyses were detected compared to 45 compounds collected by the gas-tight syringe method.

Ralstonia solanacearum and Acidovorax avenae were isolated from a wastewater treatment system manufactured with polyacrylonitrile fiber. The investigation goal is to elucidate the effectiveness of Ralstonia solanacearum and Acidovorax avenae in treating acrylic acid from synthetic wastewater and industrial wastewater. The results reveal that Ralstonia solanacearum and Acidovorax avenae could utilize acrylic acid from synthetic wastewater for growth, when the initial acrylic acid concentration was below 1,009.1 mg/l and 1,383.4 mg/l, respectively. When the acrylic acid concentration was below 606.8 mg/l, the acrylic acid removal ability reached 96.7% and 100%, respectively. Both strains could tolerate acrylamide toxicity, but only Ralstonia solanacearum could tolerate acrylonitrile toxicity. Ralstonia solanacearum and Acidovorax avenae could utilize acrylic acid from industrial wastewater for growth, when the initial acrylic acid concentration was below 1,741.1 mg/l and 1,431.2 mg/l, respectively. When the acrylic acid concentration was below 690.8 mg/l, the acrylic acid removal efficiency reached 83.5% and 62.2%, respectively. Whether the acrylic acid existed in synthetic wastewater or in industrial wastewater, the removal efficiency of acrylic acid by Ralstonia solanacearum exceeded that by Acidovorax avena.

In this work, an SPE-HPLC method coupled to photodiode array detection was validated in human urine matrix, in order to monitor four antihypertensive angiotensin II receptor antagonist drugs in patients under cardiovascular treatment. For that purpose, experimental design was used. Quantitation was accomplished by the internal standard method. The obtained LOQs were 95, 113, 125, and 85 ng/mL for eprosartan, telmisartan, irbesartan, and valsartan, respectively. The intraday and interday precision and accuracy at four concentration levels in the working range (LOQ-15 microg/mL) were always lower than 11% RSD and 8% relative error. The urine samples proved to be stable during 4 h at room temperature, after three thaw-freeze cycles, and for 2 months at -20 degrees C. No interferences from other endogenous compounds or co-administered drugs were found. The method has been successfully applied to monitor the renal elimination of eprosartan and valsartan during 24 h.

In this article, the separation and the purification of the acrylic acid produced from renewable sugars were studied using the liquid-liquid extraction process. Nonrandom two-liquids and universal quasi-chemical models and the prediction method universal quasi-chemical functional activity coefficients were used for generating liquid-liquid equilibrium diagrams for systems made up of acrylic acid, water, and solvents (diisopropyl ether, isopropyl acetate, 2-ethyl hexanol, and methyl isobutyl ketone) and the results were compared with available liquid-liquid equilibrium experimental data. Aspen Plus (Aspen Technology, Inc., version 2004.1) software was used for equilibrium and process calculations. High concentration of acrylic acid was obtained in this article using diisopropyl ether as solvent.

Objective: To study the chemical constituents of Zanthoxylum nitidum., Method: Column chromatography on Silica gel and Sephadex LH - 20, and recrystallization were applied for the isolation and purification of the constituents. The structures were elucidated on the basis of spectral analysis, chemical evidences and by comparison with the data reported in literature., Result: From the CHCl3 fraction and n-butanol fraction of the EtOH extract of the roots of Z. nitidum, 10 compounds were isolated and identified as 2, 4-dihydroxypyrimidine (1), syringic acid (2) , 2, 6-dimethoxy-1, 4-benzoquinone (3) , 4-hydroxybenzoic acid (4), ethylparaben (5), (Z)-3-(2, 3, 4-trimethoxyphenyl) acrylic acid (6), 5, 6, 7-trimethoxycoumarin (7), stigmast-9 (11) -en-3-ol (8), daucosterol (9), beta-sitosterol (10)., Conclusion: Compounds 1-9 were isolated and identified from the roots of Z. nitidum for the first time. Furthermore, we note here the first isolation of compound 6 as a natural product.

Two unique glucose esters of 3-nitropropanoic acid with acryloyl moieties, kirilowin A and kirilowin B, were isolated from the roots of Indigofera kirilowii. Their structures were elucidated by detailed spectroscopic analysis. The two acrylates constitute new additions to the toxic glucose conjugates of 3-nitropropanoic acid in angiosperms.

Acrylic acid might become an important target for fermentative production from sugars on bulk industrial scale, as an alternative to its current production from petrochemicals. Metabolic engineering approaches will be required to develop a host microorganism that may enable such a fermentation process. Hypothetical metabolic pathways for insertion into a host organism are discussed. The pathway should have plausible mass and redox balances, plausible biochemistry, and plausible energetics, while giving the theoretically maximum yield of acrylate on glucose without the use of aeration or added electron acceptors. Candidate metabolic pathways that might lead to the theoretically maximum yield proceed via beta-alanine, methylcitrate, or methylmalonate-CoA. The energetics and enzymology of these pathways, including product excretion, should be studied in more detail to confirm this. Expression of the selected pathway in a host organism will require extensive genetic engineering. A 100,000-tons/year fermentation process for acrylic acid production, including product recovery, was conceptually designed based on the supposition that an efficient host organism for acrylic acid production can indeed be developed. The designed process is economically competitive when compared to the current petrochemical process for acrylic acid. Although the designed process is highly speculative, it provides a clear incentive for development of the required microbial host, especially considering the environmental sustainability of the designed process.

Objective: To study the chemical constituents of Hedysarum polybotrys., Method: Chromatographic methods were used to isolate compounds from H. polybotrys and chemical and spectral methods were used to elucidate the structures of the isolated compounds., Result: Five compounds, N,N,N-trimethyl-tropaphone inner salt (hypaphorine) (1), octadecyl-3-methoxy-4-hydroxy-benzeneacrylate (2), 5,7,4'-trihydroxy-dihydroflavanone 5,7-di-O-beta-D-glucopyranoside (3), 3,4,5-trimethoxy cinnamic acid methy ester (4) and vanillic acid (5), were isolated from the roots of H. polybotrys., Conclusion: Compounds 1, 2 and 3 were obtained from this plant for the first time, while compounds 1 and 2 were isolated from Hedysarum for the first time.

A gas chromatographic method was developed to directly determine the enantiomers of acrylic ketone alcohol and acrylic ketone acetate. Two pairs of enantiomers were nearly baseline-separated by using Model HP-5890 Gas Chromatograph with flame ionization detector and WCOT CD-Chiral-DEX CB (30 m x 0.25 mm i.d.) column. The optimum conditions were the split ratio of 30:1 for the sample injected, the flow rates of 3.7 mL/min for the carrier gas (nitrogen), 60 mL/min for the hydrogen, and 250 mL/min for the oxygen, and temperatures of 148 degrees C for the column, 230 degrees C for the injector, and 230 degrees C for the detector. The linearity and reproducibility were satisfactory. The regression coefficients were over 0.9965. The RSDs obtained were less than 1.25%. The method was further used to trace the reactants and products, and to evaluate the enzyme catalyst activity and selectivity under different conditions. The results show that the method developed is very successful.

Objective: To study the chemical constituents of Bletilla striata., Method: The constituents were separated and purified by column chromatography with silica gel, and identified by NMR, MS and physical data., Result: Three compounds were isolated and identified as hexacosanoic alcohol 3-(4-hydroxy-3-methoxybenzol)-trans-acryliceylenate(1), physcion(2) and cyclobalanol(3)., Conclusion: Compound 1 was a new compound and compound 3 was isolated from this plant for the first time.

New antibiotic compounds, melithiazols, were isolated from the culture broth of strains of the myxobacteria Melittangium lichenicola, Archangium gephyra, and Myxococcus stipitatus. The compounds belong to the group of beta-methoxyacrylate (MOA) inhibitors and are related to the myxothiazols. The melithiazols show high antifungal activity, but are less toxic than myxothiazol A and its methyl ester in a growth inhibition assay with mouse cell cultures. The melithiazols inhibit NADH oxidation by submitochondrial particles from beef heart. Melithiazol A blocks the electron transport within the bc1-segment (complex III) and causes a red shift in the reduced spectrum of cytochrome b.

A new antifungal (E)-beta-methoxyacrylate noroudemansin A (1), was isolated from cultures of Pterula sp. 82168. Its biological activities were investigated and compared with oudemansin A. The structure was elucidated by spectroscopic methods. Three semisynthetic noroudemansin A derivatives were synthesized from the natural product.

We evaluated free radical scavenging activity of the water, methanol and chloroform extracts of propolis in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical and xanthine-xanthine oxidase (XOD) generated superoxide anion assay systems. The free radical scavenging activity guided fractionation and chemical analysis led to the isolation of a new compound, propol (3-[4-hydroxy-3-(3-oxo-but-1-enyl)-phenyl]-acrylic acid) from the water extract, which was more potent than most common antioxidants such as vitamin C and vitamin E (alpha-tocopherol) in these assay systems.

Submerged liquid cultures of the basidiomycete Favolaschia pustulosa (Xenova culture collection no. X27732) afforded the novel 9-methoxystrobilurin derivatives, 9-methoxystrobilurin L (1) and 9-methoxystrobilurin E (2), and the related oudemansin derivative, oudemansin L (3). Their structures were established by 2D NMR experiments. Compounds 1 and 3 possess a novel arrangement of two isoprenoid units fused to the aromatic nucleus. Both 1 and 2 have the EEE-configuration in the pentadienyl side chain as reported previously for 9-methoxystrobilurins. Compound 1 was cytotoxic to cells of the human B lymphoblastoid cell line (Jijoye), with an IC50 of 1.8 nM. This cytotoxicity was observed in a 5- day assay only and was not apparent after 2 days. Compound 1 showed some antibacterial activity against Bacillus subtilis (MIC = 0.9 microM) and antifungal activity against Candida albicans (MIC = 6 microM).

Hydrophobically modified poly(acrylic acids) (HMPAs) are random copolymers of sodium acrylate and dodecyl acrylamide, containing 0-10% mol/mol of dodecyl grafts. The hydrophobic character of different HMPAs of average molecular weight 150,000 was studied by capillary electrophoresis (CE), using neutral surfactants as buffer additives. The differentiation of the electrophoretic mobilities of HMPAs with their hydrophobicity was achieved through the use of nonionic Brij 35 and zwitterionic DAPS surfactants. A nearly baseline separation of the precursor and three HMPAs derivatives was obtained in a poly(ethylene glycol)-coated capillary with a background electrolyte containing 10 mM N-dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (DAPS) and 10 mM borax (pH 9.2). In addition to CE experiments, the polymer-surfactant interactions were also investigated by means of quasi-elastic light scattering (QELS) and viscosimetric measurements. According to the latter results, the separation mechanism was interpreted as an expansion of the polymer coil in the presence of micelles and subsequent change of its frictional properties. A true micellar electrokinetic capillary chromatography (MEKC) partitioning model was discarded on the basis of the relative sizes of the macromolecule and the micelles.

Following a brief review of recent discoveries in the field of natural antimutagenic and tumor chemopreventive agents, contemporary findings in the author's laboratories employing the direct acting mutagen, ethyl methanesulfonate, in modified Ames tests and eukaryotic murine FM3A mammary tumor cells modified to be subject to thymidine-less death are described to illustrate the underlying principles. The EMS studies are illustrated with the isolation of the novel antimutagen, plicatin B, from the medicinal plants, Psoralea juncaea and P. plicata. The FM3A studies are carried out with extracts of Styrax asiatica, a plant previously studied extensively with the EMS system. The FM3A findings closely parallel the earlier work with EMS showing that the responsible agents, cinnamic acid, cinnamoyl ricinoleate and cinnamoyl cinnamate are effective both in prokaryotic and eukaryotic tests and that the new FM3A assay system has useful properties for screening and assay of novel antimutagenic agents.

The rootwood of Aeschynomene mimosifolia Vatke (Leguminosae) has yielded a new neoflavonoid, mimosifoliol (1), and an unusual C16-styrylcycloheptenone derivative, mimosifolenone (2). The structures of these compounds were determined on the basis of spectral analysis. Compound 1 demonstrated weak activity in DNA-strand scission assay, while compound 2 was found to be inactive. Mimosifoliol (1) was inactive toward several human cell lines, while 2 was moderately active against the KB cell line.

A simple, sensitive fluorometric method for the determination of nitric oxide and nitric oxide synthetase in rat brain homogenates has been developed. The method is based on the absorption of a reaction product of N-acetylcysteine and nitric oxide overlapping the absorption of quinine sulfate. The lowest concentration that can be determined is 3 x 10(-8) mol.L-1.

Strobilurin E is a novel antibiotic of the (E)-beta-methoxyacrylate (MOA) class produced by mycelial cultures of the agaric Crepidotus fulvotomentosus. In addition to an inhibition of fungal respiration, a feature of all MOA-antibiotics, the compound exhibits very high cytostatic activities which are accompanied by reversible morphological alterations of the cells.

Cultures of Streptomyces lincolnensis accumulated 3-methylthioacrylic acid in amounts directly related to the concentration of methionine in the medium. The metabolite was labeled by L-(methyl-14C) but not by DL-(carboxyl-14C) methionine, indicating biosynthesis from the amino acid with loss of the carboxyl group. S. lincolnensis mycelium contained sufficient peroxidase activity to catalyse oxidative decarboxylation of L-methionine to 3-methylthiopropionamide as the initial step of a biosynthetic sequence. The enzyme, partially purified by ammonium sulfate precipitation, chromatography on a DEAE-cellulose column ang gel filtration, had a molecular weight of approximately 350,000, a pH optimum of 6.0, with o-dianisidine as electron donor and a Km value of 7.5 x 10(-4) M with respect to hydrogen peroxide. Cultures of S. lincolnensis supplemented with 3-(methyl-14C) methylthiopropionic acid gave labeled 3-methylthioacrylic acid. However, 3-(methyl-14C) methylthiopropionamide did not label the metabolite, suggesting that the first intermediate in the pathway may be the keto acid, which is then oxidatively decarboxylated to 3-methylthiopropionic acid.

Poly(2-hydroxyethyl methacrylate) is nowadays accepted as a biocompatible, safe and stable hydrogel for medical use. In this paper, the use of thin-layer chromatography for the analysis and small-scale preparation of the initial monomer, 2-hydroxyethyl methacrylate, is described. Development on silica gel, with n-hexane-diethyl ether (1:1, v/v) and/or n-hexane-isobutyl methyl ketone-n-octanol (9:2:1, v/v; saturated with 25% nitric acid) is recommended for qualitative analysis. Preparative-scale work is preferably carried out on sulphuric acid-impregnated silica gel, with n-hexane-diethyl ether (1:1, v/v) as mobile phase. Inhibitors are detected by thin-layer chromatography and a drop-test procedure with diazotised sulphanilic acid. The nature of the contaminants present in several commercial samples of 2-hydroxyethyl methacrylate is discussed. n20D values are reported for the system 2-hydroxyethyl methacrylate-water.

Pure glycol methacrylate (GMA) is an excellent embedding medium which allows High Performance Optical Microscopic studies. However presence of methacrylic acid (MA) small amounts (usually 1 to 3%) leads to intense background staining of the section. A simple and reliable chemical purification procedure is exposed which leads to an extra-pure GMA free of MA and hydroquinone.

Two new antifungal (E)-beta-methoxyacrylates, strobilurin C and oudemansin B, were isolated from cultures of Xerula longipes and Xerula melanotricha. Their structures were elucidated by spectroscopic methods. Both antibiotics inhibit the growth of a wide variety of saprophytic and phytopathogenic fungi at very low concentrations. Like strobilurins A, B, and oudemansin A the new metabolites are potent inhibitors of respiration.

A simple procedure for removing methacrylic acid from water-miscible methacrylates is described. One volume of monomer is diluted with 9 volumes of diethyl ether. Three consecutive extractions are carried out with 5% aqueous NaHCO3 at 4 C. Residual water is removed by shaking with anhydrous sodium sulfate. The ether is removed by flash evaporation on a Büchi Rotavapor. Weak alkali extraction produces good quality semithin sections which are free of background staining. This method may be a useful alternative to existing methods for removal of methacrylic acid.

A new porphyrin isolated from calf and foal meconium has been characterized as a tris-(2-carboxyethyl)-mono-(2-carboxyvinyl)-tetramethyl porphin, that is as an analogue of coproporphyrin in which one propionate group has been replaced by an acrylate group. The porphyrin is mainly a type III isomer and its possible significance in haem biosynthesis is discussed.