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In view of limited information, a laboratory experiment was conducted to study the stability of organo-arsenic complexes as affected by competing anions i.e. phosphate, nitrate and sulphate. For this purpose, humic acid (HA) and fulvic acid (FA) were extracted from farmyard manure (FYM), vermicompost (VC), sugarcane bagasse (SB) and soil. A pot experiment was also conducted with 4 levels each of arsenic (As) (10, 20, 30 and 40  mg  kg -1 ) and amendments (no amendment, FYM, VC and SB at the rate of 10  t  ha -1 each). Results indicate that stability of FA extracted from sugarcane bagasse have the highest stability constant (log K) as 9.77 and the corresponding mole ratio (x) value of 1.51. The phosphate was the most effective in replacing As from organo-As complexes followed by sulphate and nitrate. Under pot culture study, As content in wheat grain was the lowest in sugarcane bagasse amended soil followed by FYM and VC at all levels of As application. Solubility-free ion activity model was most effective in predicting As uptake by wheat grain based on Olsen extractable As, pH and Walkley & Black organic C. Efficacy of organic amendments in reducing health hazard for intake of As through consumption of wheat grain grown on contaminated soil was also reflected in the values of hazard quotient (HQ)., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Chemical investigation of an endophytic fungus Chaetomium globosum isolated from leaves of Wikstroemia uva-ursi led to the isolation of two new azaphilones, chaetoviridins J and K (1 and 3), along with five known derivatives (2 and 4-7). The structures of azaphilones were determined by NMR, X-ray diffraction, Mosher's method, and CD analysis. The isolated compounds were evaluated for their cancer chemopreventive-potential based on their abilities to inhibit tumor necrosis factor alpha (TNF-α)-induced nuclear factor-kappa B (NF-κB). Compounds 4, 5, 7, and synthetic 8 and 9 inhibit nitric oxide (NO) production with IC50 values in the range of 0.3-5.8 μM. Compounds 4, 5, and 9 also displayed (TNF-α)-induced NF-κB activity with IC50 values in the range of 0.9-5.1 μM., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Rhus verniciflua Stokes has been used as a traditional herbal medicine in Asia. In this study, the effect of R. verniciflua extract on human aromatase (cytochrome P450 19, CYP19) activity was investigated to elucidate the mechanism for the effect of R. verniciflua extract on androgen hormone levels. Androstenedione was used as a substrate and incubated with R. verniciflua extract in cDNA-expressed CYP19 supersomes in the presence of NADPH, and estrone formation was measured using liquid chromatography-tandem mass spectrometry. R. verniciflua extract was assessed at concentrations of 10-1000 μg/mL. The resulting data showed that R. verniciflua extract inhibited CYP19-mediated estrone formation in a concentration-dependent manner with an IC50 value of 136 μg/mL. Subsequently, polyphenolic compounds from R. verniciflua extract were tested to identify the ingredients responsible for the aromatase inhibitory effects by R. verniciflua extract. As a result, butin showed aromatase inhibitory effect in a concentration-dependent manner with an IC50 value of 9.6 μM, whereas the inhibition by other compounds was negligible. These results suggest that R. verniciflua extract could modulate androgen hormone levels via the inhibition of CYP19 activity and butin is a major ingredient responsible for this activity., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Centrifugal partition chromatography (CPC) can be used to isolate various bioactive compounds from natural materials by one-step. We confirmed antioxidative compounds existed in chloroform (CHCl3) fraction of Sargassum siliquastrum using online-HPLC. Fractions (A, B, C, D and E) were separated from the CHCl3 fraction by preparative CPC (n-hexane:ethyl acetate:methanol:water, 5:5:7:3, v/v). In this study, we proved that the isolated compounds exhibit anti-inflammatory activities using lipopolysaccharide (LPS) stimulated RAW 264.7 macrophages. The fraction A which exhibited the strongest inhibitory effect on nitric oxide (NO) production level, was confirmed as sargachromanol E by LC-MS-ESI, (1)H NMR and (13)C NMR data. The sargachromanol E significantly reduced the inflammatory response in LPS induced macrophages, decreasing LPS-induced transcription factor of pro-inflammatory cyclooxygenase-2, NO synthase, phosphate P38, phosphate ERK1/2, LPS-stimulated tumor-necrosis factor alpha, interleukin-1 beta and prostaglandin E2 release. In conclusion, it was suggested that sargachromanol E inhibited inflammation in LPS induced RAW 264.7 cells via MAPK pathway., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Oxidation is well-known process of transforming natural organic matter during the treatment of drinking water. Chlorine, ozone, and chlorine dioxide are common oxidants used in water treatment technologies for this purpose. We studied the influence of different doses of these oxidants on by-products formation and changes in biodegradable dissolved organic carbon (BDOC) and molecular weight distribution (MWD) of fulvic acids (FA) with different BDOC content. Chlorination did not significantly change the MWD of FA and disinfection by-products formation. However, higher molecular weight compounds, than those in the initial FA, were formed. It could be a result of chlorine substitution into the FA structure. Chlorine dioxide oxidized FA stronger than chlorine. During ozonation of FA, we found the highest increase of BDOD due to the formation of a high amount of organic acids and aldehydes. FA molecules were transformed into a more biodegradable form. Ozonation is the most preferable process among those observed for pre-treatment of FA before biofiltration., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Three novel azaphilone alkaloids, namely chaetomugilides A-C (1-3), together with three related compounds (4-6) were isolated from the methanol extract of Chaetomium globosum TY1, an endophytic fungus isolated from Ginkgo biloba. Their structures were elucidated on the basis of extensive 1D and 2D NMR as well as HRESI-MS spectroscopic data analysis. The isolated compounds exhibited highly cytotoxic activities against human cancer cell line HePG2 with the IC50 values range from 1.7 to 53.4μM., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

A new microbial metabolite, cytosporone S (1) was isolated from a fermentation broth of the fungus Trichoderma sp. FKI-6626. Its chemical structure was determined primarily by NMR spectroscopy and mass spectrometry. Compound 1 showed antimicrobial activity against several Gram-positive and Gram-negative bacteria and fungi., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Two new phenolics, (3S,4R)-3,7,2',3'-tetrahydroxy-3,4-dihydro-9H-indeno[6,5-c]chromene (caesalpiniaphenol E, 1), and (3R,4S)-3,7-dihydroxy-3-(3'-methoxy-4'-hydroxyphenyl)-4-methoxychroman (caesalpiniaphenol F, 2), together with eleven known compounds (3-13), were isolated from the heartwood of Caesalpinia sappan. Their chemical structures were established mainly by 1D and 2D NMR techniques and mass spectrometry. Their anti-inflammatory activity was evaluated against LPS-induced NO production in macrophage RAW264.7 cells. Among them, compounds 10 and 13 showed strong inhibitory activities toward the LPS-induced NO production in macrophage RAW264.7 cells, with IC(50) values of 12.5 and 8.1 μm, respectively. In addition, compounds 10 and 13 inhibited the inductions of iNOS mRNA in dose-dependent manners, indicating that these compounds attenuated the synthesis of these transcripts at the transcriptional level., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

High-performance liquid chromatography-size exclusion chromatography (HPLC-SEC) coupled with a multiple wavelength absorbance detector (200-445 nm) was used in this study to investigate the apparent molecular weight (AMW) distributions of dissolved organic matter (DOM). Standard DOM, namely humic acid, fulvic acid and hydrophilic acid, from the Suwannee River were tested to ascertain the performance and sensitivity of the method. In addition to four compounds groups: humic substances (Peak 1, AMW 16 kD), fulvic acids (Peak 2, AMW 11 kD), low AMW acids (Peak 3, AMW 5 kD), and low AMW neutral and amphiphilic molecules, proteins and their amino acid building blocks (Peak 4, AMW 3 kD), an new group that appears to include low AMW, 6-10 kD, humic substances was found based on investigating the spectra at various elution times. The spectroscopic parameter S(>365) (slope at wavelengths >365 nm) was determined to be a good predictor of the AMW of the DOM. The detector wavelength played an important role in evaluating the AMW distribution. For some fractions, such as the humic and low AMW non-aromatic substances, the error in measurement was ± 30% as determined by two-dimensional chromatograms detected at an artificially selected wavelength. HPLC-SEC with multiple wavelength absorbance detection was found to be a useful technique for DOM characterization. It characterized the AMW distributions of DOM more accurately and provided additional, potentially important information concerning the properties of DOM with varying AMWs., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Two novel benzylazaphilone derivatives with an unprecedented carbon skeleton, aspergilone A (1), and its symmetrical dimer with a unique methylene bridge, aspergilone B (2), have been isolated from the culture broth of a marine-derived fungus Aspergillus sp. from a gorgonian Dichotella gemmacea. Their structures and relative stereochemistries of 1 and 2 were elucidated using a combination of NMR spectroscopy and X-ray crystallography. Compound 1 not only exhibited in vitro selective cytotoxicity but also showed potent antifouling activity., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

An equilibrium dialysis combined with a (14)C-labeling method was used to study the abiotic association of phthalic acid esters (PAEs) with dissolved humic substances (HS) and its influence on the fate of PAEs in landfill leachate. Elemental analysis and FTIR spectral analysis were carried out on the humic acid (HA) and fulvic acid (FA) components of HS to examine the relationship between the structure of HS and the intensity of the association of the PAEs with HS (K(A)). The results show that the association intensity of HS with PAEs depends greatly on both the properties of the PAEs and the source of HS. The HS have a strong association reaction with dibutyl phthalic acid, which might explain the higher concentration of dibutyl phthalic acid detected in landfill leachate. The pH value strongly affects the K(A) of HS, and it decreases radically when the pH increase from 3.0 to 9.0. The non-specific hydrophobic interaction between HS and PAEs plays a more important role in the abiotic association of HS with PAEs. Elemental analysis and FTIR spectra suggest that the high K(A) values are related to the high aromatic content and larger molecular weight of HS., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

Bioactivity-directed investigation of root extract of Derris scandens has led to the isolation and characterization of a new benzil derivative (11), along with ten known compounds (1-10). Their structures were determined on the basis of extensive spectroscopic (IR, MS, 1D and 2D NMR) data analysis and by comparison with the literature data. The insect antifeedant activity and growth inhibitory studies of these compounds were investigated against castor semilooper pest, Achaea janata using a no-choice laboratory bioassay. Several of the isolates displayed potent feeding deterrence and were also toxic or caused developmental abnormalities following topical administration. The new compound, derrisdione A was moderately active with an antifeedant index of 58.6+/-1.7% at 10microg/cm(3) against A. janata., (Copyright 2009 Elsevier Ltd. All rights reserved.)

Puupehanol (1), a new sesquiterpene-dihydroquinone derivative, was isolated from the marine sponge Hyrtios sp., along with the known compounds puupehenone (2) and chloropuupehenone (3) that are responsible for the antifungal activity observed in the extract. The structure of 1 was established as (20R,21R)-21-hydroxy-20,21-dihydropuupehenone by extensive spectroscopic and computational methods. Compound 2 exhibited potent activity against Cryptococcus neoformans and Candida krusei with MFCs of 1.25 and 2.50 microg/mL, respectively.

We have investigated anticholinesterase potential of the methanol extracts from the leaf, wood, flower, twig, and stem bark of the female and male individuals and rhizodermis and fruit from the female tree of Maclura pomifera (Rafin.) Schneider (Moraceae) along with its major isoflavonoids; osajin and pomiferin as well as their semi-synthetic derivatives; iso-osajin and iso-pomiferin. Anticholinesterase activity was determined by Ellman method using ELISA microplate reader. Osajin and pomiferin had a noticeable inhibition of AChE with IC(50) values of 2.239 and 0.096 mM, respectively, while their iso-derivatives were found to display less inhibition towards AChE. The extracts and compounds did not inhibit BChE. The extracts were analyzed for osajin and pomiferin contents by LC-DAD-MS and only the fruits and female flowers contained osajin (fruit: 8.87%, female flowers: 0.19%, w/w) and pomiferin (fruit: 13.6%, female flowers: 0.36%, w/w).

Novel results were obtained when a fulvic acid was isolated from Acros humic acid and fractionated by traditional preparative thin-layer chromatography. Eight colorful bands were directly viewed and analyzed showing very different fluorescence and absorption properties. The fluorescence quantum yield of the bands ranged from 2% to 9.4%, significantly higher than that of natural humic substances. An aqueous fulvic acid solution was also extracted with methylene chloride (CH(2)Cl(2)) by continuous liquid-liquid extraction. The CH(2)Cl(2) extract was further fractionated by thin-layer chromatography. Eleven highly fluorescent colorful bands and six weakly fluorescent bands were observed and examined. UV-vis absorption and fluorescence (including 3D matrix) spectra and fluorescence quantum yields revealed that each band still represented a mixture of compounds. Moreover, substantial differences in optical properties were observed among bands. A single band possessed the highest fluorescence quantum yield (6%) and highest specific fluorescence (fluorescence/mass), and accounted for 21% of the total fluorescence of the extract. The mass of individual bands varied from 1.6% to 14.1% of the total materials recovered. Components of all fractions were grouped into 11 fluorophore families according to their maxima on 3D matrix fluorescence spectra. No component is dominant in the whole fulvic acid or extracted portion in terms of optical properties. Over 40 natural products are proposed for model chromophores.

The pulp and paper industry generates large volume of wastewater that adversely affects water resources. Lignin derived macromolecular compounds, similar to natural humic substances, are the main waste products in the pulp mill effluents. The UV-Vis and fluorescence spectroscopies were used to assess the effect of solar exposition on fulvic acids from a kraft pulp mill effluent. Solar irradiation of the solutions of these fulvic acids caused solution acidification and decay both in the UV-Vis absorbance and in the fluorescence. This decay was not the same for the whole spectra but pointed to the selective photodegradation of lignin typical structures. Furthermore, by sequential ultrafiltration it was found that during irradiation, the high-molecular weight fractions were destroyed and low-molecular-weight constituents, potentially more able to penetrate the cell membranes of living organisms were formed. Photodegradation of macromolecular organic matter from a kraft pulp mill effluent may be a key process occurring in natural waters that modifies the physicochemical properties of such effluents.

The major constituents from the fruits of Maclura pomifera are the prenylated isoflavones, osajin (1) and pomiferin (2). Their structures were elucidated using NMR spectroscopic techniques and mass spectrometric analysis. Compound 2 showed potential inhibitory activity in histone deacetylase (HDAC) enzyme assay. It also exhibited growth inhibitory activity on five human tumor cell lines and more sensitive inhibitory activity on the HCT-15 colon tumor cell line. Further structure-activity relationships of position 3 on ring B from aromatic ring will be reported in due course.

The 80% aqueous acetone extracts from the fruit (50 mg/kg/d) and seeds (12.5 and 25 mg/kg/d) of Rosa canina L., but not from the pericarps, were found to show substantial inhibitory effect on the gain of body weight and/or weight of visceral fat without affecting food intake in mice for 2 weeks after administration of the extracts. With regard to the active constituents, the principal constituent, trans-tiliroside (0.1-10 mg/kg/d), potently inhibited the gain of body weight, especially visceral fat weight, and significantly reduced blood glucose levels after glucose loading (1 g/kg, ip) in mice. On the other hand, kaempferol and p-coumaric acid lacked such effect and kaempferol 3-O-beta-D-glucopyranoside tended to reduce the gain of body weight and visceral fat weight, but not significantly, at a dose of 10 mg/kg/d. These results indicate the importance of both kaempferol 3-O-beta-D-glucopyranoside and p-coumaroyl moieties for anti-obese effects. Furthermore, a single oral administration of trans-tiliroside at a dose of 10 mg/kg increased the expression of PPAR-alpha mRNA of liver tissue in mice.

Due to the growing concern of highly contaminated landfill leachate problems in Taiwan, an innovative advanced catalytic oxidation (FeGAC/H(2)O(2)) process was developed and employed in this research to treat the landfill leachate from central Taiwan. Experimental results indicated that the FeGAC/H(2)O(2) process could effectively remove organic compounds from landfill leachate. The presence of iron oxide coated granular activated carbon (FeGAC) greatly improved the oxidative ability of H(2)O(2) for the removal of humic acids, fulvic acids and non-humic substance from leachate. For instance, at pH 6, the removal efficiencies of FeGAC/H(2)O(2) and H(2)O(2) processes were 70% and 8%, respectively. FeGAC/H(2)O(2) combined both advantages of FeGAC and H(2)O(2) where FeGAC had good organics adsorption ability and could effectively catalyse the hydrogen peroxide oxidation reaction for organics removal.

Two new compounds, a cyclopenta[bc]benzopyran, ponapensin (1), and an aglaialactone, 5,6-desmethylenedioxy-5-methoxy-aglalactone (2), together with nine known compounds were isolated from the CHCl(3) soluble extract of the leaves and twigs of Aglaia ponapensis. Their structures were established by spectroscopic data interpretation. Ponapensin (1) exhibited significant NF-kappaB inhibitory activity in an Elisa assay, and was found to be more potent than the positive control rocaglamide. All of the compounds isolated were also tested in a panel of human cancer cell lines, with the known sterol E-volkendousin (3) and methyl rocaglate (aglafoline) found to be the only active substances.

This paper aims to explore potassium ferrate(VI) (K2FeO4) as an alternative water treatment chemical for both drinking water and wastewater treatment. The performance of potassium ferrate(VI) was evaluated in comparison with that of sodium hypochlorite (NaOCl) and that of NaOCl plus ferric sulphate (FS) or alum (AS). The dosages of ferrate(VI), NaOCl and FS/AS and sample pH values were varied in order to investigate the effects of these factors on the treatment performance. The study demonstrates that in drinking water treatment, ferrate(VI) can remove 10-20% more UV(254)-abs and DOC than FS for the same dose compared for natural pH range (6 and 8). The THMFP was reduced to less than 100 microg l(-1) by ferrate(VI) at a low dose. In addition to this, ferrate(VI) can achieve the disinfection targets (>6 log10 inactivation of Escherichia coliform (E. coli)) at a very low dose (6 mg l(-1) as Fe) and over wide working pH in comparison with chlorination (10 mg l(-1) as Cl2) plus coagulation (FS, 4 mg l(-1) as Fe). In wastewater treatment, ferrate(VI) can reduce 30% more COD, and kill 3log10 more bacteria compared to AS and FS at a similar or even smaller dose. Also, potassium ferrate(VI) can produce less sludge volume and remove more pollutants, which could make sludge treatment easier.

Excitation/emission matrix (EEM), single-scan excitation and synchronous fluorescence spectra of a series of FA and HA from distinct environments are presented. The EEM plots show at least four spectral features whose corresponding Ex/Em pairs relate to the alpha', alpha, beta and gamma (or delta) fluorophores previously found in natural waters spectra. The alpha' and alpha peaks, which identify typical humic-like components, are present in all samples, independently of the organic matter (OM) source. In FA, their Ex/Em pairs are approximately 260 nm/460 nm and approximately 310 nm/440 nm, respectively. In HA their excitation and emission maxima are red-shifted, the corresponding Ex/Em pairs being located at approximately 265 nm/525 nm and approximately 360 nm/520 nm, respectively. The appearance of beta and gamma (or delta) peaks is dependent both on the OM origin and on HS aging. The former (Ex/Em approximately 320 nm/430 nm), that has been associated with the incidence of marine humic-like material, is present only in a few marine and estuarine HA. It emerges as a shoulder on the alpha peak and its detection is dependent on a balance between its magnitude and the magnitude and emission maxima location of the alpha peak. The gamma (or delta) peak (Ex/Em approximately 275 nm/315 nm in FA, and approximately 275 nm/330 nm in HA), on the other hand, is better visualized in FA than in HA diagrams. It has typical protein-, mainly tryptophan-like, fluorescence properties and appears with varied significance in a few marine and estuarine samples being hardly detected in samples from exclusively terrestrial environments. It is also shown in this study that with selected lambda(ex), lambda(em) and (delta)(lambda) values, regular emission, excitation and synchronous spectra can, together, provide a good picture of the OM sources and aging for extracted HS.

Edunol (3), a pterocarpan isolated from Harpalyce brasiliana, a plant used in the northeast of Brazil against snakebites, was obtained by synthesis and showed antimyotoxic, antiproteolytic and PLA2 inhibitor properties. These proprieties could be improved through the synthesis of a bioisoster (5), where the prenyl group was replaced by the benzyl group.

Leporin B (1), a novel demethylated analogue of leporin A (2), was isolated from a taxonomically unidentified fungal strain as part of an effort to discover compounds with the ability to increase expression levels of the enzyme hexokinase II. The structure was determined by spectral methods, including 1D and 2D NMR, and HRMS. The relative stereochemistry was assigned by NOESY experiments and coupling constants.

Humic and fulvic acids extracted from soils of different genesis were investigated for their ability to photoinduce the transformation of fenuron (2 x 10(-4) mol(-1)) at 365 nm. The ratio of the initial rate of fenuron consumption over the rate of light absorption by humic substances was found to be higher for fulvic acids (range 2.0 x 10(-3) to 9.0 x 10(-5)) than for humic acids (range 1.7 x 10(-4) to - 3.6 x 10(-5)). Within the FAs population, this ratio decreased as the specific absorption coefficient at 365 nm increased. It seems therefore that most of 365-nm absorbing components have no photoinductive activity and even reduce that of photoinductive chromophores.