Unlocking the Therapeutic Potential of Freshwater Sapropel Extracts: In Vitro Analysis and Antioxidant Profiling for Skincare Applications.

Background and Objective: Sapropel, a biologically active sedimentary deposit, is high in organic matter and minerals and has been shown to offer health benefits. Its constituents, humic acid (HA) and fulvic acid (FA), have been found to have some therapeutic applications. The aim of this study was to determine the potential therapeutically significant properties of freshwater sapropel extracts: their polyacid content, antioxidative (AO) status, and biological activity in cell culture. Materials and Methods: Freshwater lakes from the southeast region of Latvia were investigated layer by layer. The total organic carbon (TOC) was determined through combustion using the catalytic oxidation method, HA and FA were measured via acid perspiration, and the total polyphenol content (TPC) and total antioxidant status (TAS) was analysed spectrophotometrically. Sapropel extracts' regenerative abilities were tested in vitro using a Cell-IQ real-time monitoring system on mouse BALB/c 3T3 fibroblasts and human keratinocyte HaCaT cell lines. Cytotoxicity was measured through neutral red uptake assessment as a concentration-dependent reduction in the uptake of neutral red dye relative to a vehicle control or untreated cells. Results: The highest AO activity was observed in sapropel extracts with elevated concentrations of HA and TPC from Audzelu Lake (1.08 ± 0.03 mmol/L), and the lowest activity was found in extracts from Ivusku Lake (0.31 ± 0.01 mmol/L). Correspondingly, the concentrations of HA in Audzelu and Ivusku Lakes were recorded as 45.2 and 27.4 mg/g, respectively. High concentrations of HA promoted in vitro cell growth upon short-term exposure (up to 6 h). Conclusions: The results show that high TPC correlates with AO status and sapropel extracts with higher concentrations of HA exhibit greater AO activity and promote in vitro cell growth, suggesting a perspective use for short-term topical therapeutic skin applications. However, higher concentrations over longer durations showed cytotoxic effects, indicating the need for further investigation.

Metabolites in Conocarpus erectus leaves attenuate α-amylase activity by modulating amino acid residues of α-amylase: an in vitro and docking study / Los metabolitos en las hojas de Conocarpus erectus atenúan la actividad de la α-amilasa al modular los residuos de aminoácidos de la α-amilasa: un estudio in vitro y de acoplamiento

The antioxidant activity and the inhibitory potential of α-amylase of lyophilized hydroethanolic extracts of Conocarpus erectus leaves obtained by ultrasonication were determined. The most potent extract was subjected to ultra-high performance liquid chromatography system equipped with mass spectrometer for metabolite identification. The identified metabolites were docked in α-glucosidase to assess their binding mode. The results revealed that 60% ethanolic extract exhibited highest ferric reducing antioxidant power (4.08 ± 0.187 mg TE/g DE) and α-amylase inhibition (IC50 58.20 ± 1.25 µg/mL. The metabolites like ellagic acid, 3-O-methyl ellagic acid, ferujol, 5, 2 ́-dihydroxy-6,7,8-trimethyl flavone and kaempferol glucoside were identified in the extract and subjected to molecular docking studies regarding α-amylase inhibition. The comparison of binding affinities revealed 3-O-methyl ellagic acid as most effective inhibitor of α-amylase with binding energy of -14.5911 kcal/mol comparable to that of acarbose (-15.7815 kcal/mol). The secondary metabolites identified in the study may be extended further for functional food development with antidiabetic properties.

Se determinó la actividad antioxidante y el potencial inhibidor de la α-amilasa de extractos hidroetanólicos liofilizados de hojas de Conocarpus erectus obtenidos por ultrasónicación. El extracto más potente se sometió a un sistema de cromatografía líquida de ultra alto rendimiento equipado con un espectrómetro de masas para la identificación de metabolitos. Los metabolitos identificados se acoplaron en α-glucosidasa para evaluar su modo de unión. Los resultados revelaron que el extracto etanólico al 60% exhibió el mayor poder antioxidante reductor férrico (4.08 ± 0.187 mg TE/g DE) e inhibición de la α-amilasa (IC50 58.20 ± 1.25 µg/mL. Los metabolitos como el ácido elágico, 3-O-metil elágico ácido, ferujol, 5, 2 ́-dihidroxi-6,7,8-trimetil flavona y kaempferol glucósido se identificaron en el extracto y se sometieron a estudios de acoplamiento molecular con respecto a la inhibición de la α-amilasa. La comparación de las afinidades de unión reveló 3-O-metil El ácido elágico como inhibidor más eficaz de la α-amilasa con una energía de unión de -14,5911 kcal/mol comparable a la de la acarbosa (-15,7815 kcal/mol). Los metabolitos secundarios identificados en el estudio pueden ampliarse aún más para el desarrollo funcional de alimentos con propiedades antidiabéticas.

RIFM fragrance ingredient safety assessment, 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel-, CAS Registry Number 943723-15-7.

The existing information supports the use of this material as described in this safety assessment. 5,8-Methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- was evaluated for genotoxicity, repeated dose toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization, and environmental safety. Data from read-across analog 5,8-methano-2H-1-benzopyran-2-one, 6- ethylideneoctahydro- (CAS # 69486-14-2) show that 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- is not expected to be genotoxic. The repeated dose, reproductive, and local respiratory toxicity endpoints were evaluated using the TTC for a Cramer Class III material, and the exposure to 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- is below the TTC (0.0015 mg/kg/day, 0.0015 mg/kg/day, and 0.47 mg/day, respectively). Data provided 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- a NESIL of 8200 µg/cm2 for the skin sensitization endpoint. The phototoxicity/photoallergenicity endpoints were evaluated based on human study data and UV/Vis spectra; 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- is not expected to be phototoxic/photoallergenic. The environmental endpoints were evaluated; 5,8-methano-2H-1-benzopyran, 6(or 7)-ethylideneoctahydro-, [4aR,5S,8S,8aS(or 4aR,5R,8S,8aR)]-rel- was found not to be PBT as per the IFRA Environmental Standards, and its risk quotients, based on its current volume of use in Europe and North America (i.e., PEC/PNEC), are <1.

Organic Matter Characterization and Phytotoxic Potential Assessment of a Solid Anaerobic Digestate Following Chemical Stabilization by an Iron-Based Fenton Reaction.

Digestates, a byproduct of the anaerobic bioconversion of organic wastes for the production of biogas, are highly variable in chemical and biological properties, thus limiting their potential use in agriculture as soil amendment. Using a lab-scale glass reactor, we aimed to assess the feasibility to chemically stabilize the solid fraction of an anaerobic digestate by applying a Fenton reaction under constant pH (3.0), temperature (70 °C), reaction time (8 h), and various combinations of H2O2 and Fe2+. In Fenton-treated samples, the phytotoxic potential (determined on a test plant), total phenols, and the bad smell odor index markedly declined, whereas total C and N remained unaltered. Thermogravimetric (TG) analysis and Fourier transform infrared (FT-IR) spectroscopy revealed contrasting changes in extracted humic and fulvic fractions being increased or depleted, respectively, in aromatic substances. Process feasibility and optimum conditions for an effective biomass stabilization were achieved with a H2O2/Fe2+ ratio between 0.02 and 0.03.

A Fulvic Acid-like Substance Participates in the Pro-inflammatory Effects of Cigarette Smoke and Wood Smoke Particles.

We tested the postulates that (1) a fulvic acid (FA)-like substance is included in cigarette smoke and wood smoke particles (WSP) and (2) cell exposure to this substance results in a disruption of iron homeostasis, associated with a deficiency of the metal and an inflammatory response. The fluorescence excitation-emission matrix spectra of the water-soluble components of cigarette smoke condensate and WSP (Cig-WS and Wood-WS) approximated those for the standard reference materials, Suwanee River and Nordic fulvic acids (SRFA and NFA). Fourier transform infrared spectra for the FA fraction of cigarette smoke and WSP (Cig-FA and Wood-FA), SRFA, and NFA also revealed significant similarities (O-H bond in alcohols, phenols, and carboxylates, C═O in ketones, aldehydes, and carboxylates, and a significant carboxylate content). After exposure to Cig-WS and Wood-WS and the FA standards, iron was imported by respiratory epithelial cells, reflecting a functional iron deficiency. The release of pro-inflammatory mediators interleukin (IL)-8 and IL-6 by respiratory epithelial cells also increased following exposures to Cig-WS, Wood-WS, SRFA, and NFA. Co-exposure of the respiratory epithelial cells with iron decreased supernatant concentrations of the ILs relative to exposures to Cig-WS, Wood-WS, SRFA, and NFA alone. It is concluded that (1) a FA-like substance is included in cigarette smoke and WSP and (2) respiratory epithelial cell exposure to this substance results in a disruption of iron homeostasis associated with both a cell deficiency of the metal and an inflammatory response.

Analytical methodology to screen UV-filters and synthetic musk compounds in market tomatoes.

A Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) methodology followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) analysis was developed to extract thirteen synthetic musk compounds (SMCs: cashmeran, celestolide, phantolide, traseolide, galaxolide, tonalide, musk ambrette, musk xylene, musk ketone, musk tibetene, musk moskene, ethylene brassylate and exaltolide) and six ultraviolet-filters (UVFs: 2-ethylhexyl 4-dimethylaminobenzoate, 3-(4'-methylbenzylidene) camphor, 2-ethylhexyl 4-methoxycinnamate, 2-ethylhexyl 2-cyano-3,3-diphenylacrylate, benzophenone and drometrizole trisiloxane) from tomatoes. The proposed methodology was optimized: 2 g of freeze-dried tomato was extracted with 4 mL of water and 10 mL of ethyl acetate, adding 6 g of MgSO4 and 1.5 g of NaCl, then a dispersive solid-phase extraction was performed using 3 g of MgSO4, 300 mg of primary-secondary amino adsorbent (PSA) and 300 mg of octadecyl-silica (C18). Validation delivered recoveries between 81 (celestolide) and 119% (musk tibetene), with relative standard deviations <10%. The instrumental limit of detection varied from 0.02 (2-ethylhexyl 4-methoxycinnamate) to 3.00 pg (exaltolide and musk xylene). Regarding the method quantification limits, it ranged between 0.4 (celestolide) and 47.9 ng g-1 dw (exaltolide). The method was applied to different varieties of tomatoes (Solanum lycopersicum), revealing UVFs and SMCs between 1 and 210 ng g-1 dw. Higher concentrations were found for benzophenone (29-210 ng g-1 dw) and galaxolide (9-53 ng g-1 dw). The risk associated to the ingestion of contaminated tomatoes has also been estimated, showing that a potential health risk is unlikely.

Sorption of Tonalide, Musk Xylene, Galaxolide, and Musk Ketone by microplastics of polyethylene and polyvinyl chloride.

The effects of time, temperature, and salinity on the adsorption of Tonalide (AHTN), Musk Xylene (MX), Galaxolide (HHCB), and Musk Ketone (MK) by microplastics of polyethylene (PE) and polyvinyl chloride (PVC) are studied. Results indicate that the equilibrium sorption time was about 10 h and the adsorption kinetics model conformed to the first-order adsorption kinetic model and pseudo-second order kinetic model, this indicates that the main adsorption mechanism might be chemical adsorption and physical absorption. Adsorption reached a nadir at 15 °C and 14% salinity. The adsorption capacity gradually increases, and then decreases, finally increases with an increase in NaCl concentration. Due to the specific surface area and the pore volume of PVC was larger than PE, the adsorption capacity of PVC was higher than that of PE in the equal conditions.

In vivo pro-angiogenic effects of dracorhodin perchlorate in zebrafish embryos: A novel bioactivity evaluation platform for commercial dragon blood samples.

Dragon blood has been used in wound treatment for many years and can be obtained from several distinct plant species. Dracorhodin, the active substituent of dragon blood, is a characteristic compound of the palm tree, Daemonorops draco. At present, the only method to evaluate the quality of commercial dragon blood samples is a HPLC method which determines the amount of dracorhodin in a dragon blood sample. In this study, we used zebrafish embryos as a platform to demonstrate the in vivo pro-angiogenic activity of dracorhodin perchlorate, the chemically synthesized analog of dracorhodin. By using this platform, three different commercial dragon blood samples were also examined. Our results clearly show that even though the commercial dragon blood samples had similar amounts of dracorhodin, they showed highly variable biological activity, such as pro-angiogenic effects and toxicity. In short, an in vivo activity assay platform for rapidly examining the biological activity of commercial dragon blood samples was successfully established here, which complements the current HPLC-based assay method.

Organic carbon content and humus composition after application aluminum sulfate and rice straw to soda saline-alkaline soil.

The soil organic carbon accumulation in soda saline-alkaline soil and the humus composition changes with application of aluminum sulfate and rice straw were investigated by the controlled simulative experiments in laboratory. For evaluating the amelioration effect, organic carbon content and humus composition in soda saline-alkaline soil were investigated with different application amounts of rice straw and aluminum sulfate. Potassium dichromate oxidation titration (exogenous heat) method and Kumada method were used to analyze the contents of organic carbon and humus composition, respectively. The transformation of soil organic matter in the saline-alkali soil during the amelioration has been clarified in this paper. The results demonstrated that the contents of soil organic carbon were significantly increased (13-92%) with different application amounts of rice straw and aluminum sulfate. The contents of free fraction and combined fraction of humus and their compositions (humic acid and fulvic acid) were increased with different application amounts of rice straw. The free fraction of humus was increased more dramatically. Due to aluminum sulfate application, free fraction of humus and humic acid (HA) was transformed to combined fraction partially. Free HA was changed to be P type with rice straw application. With aluminum sulfate application, free form of HA was changed from type P to type Rp. For rice straw application, combined HA only was transferred within the area of type A. Aluminum sulfate addition had no significant effect on the type of combined form of HA. With the same amount of rice straw application, the contents of soil organic carbon were increased by increasing the amount of aluminum sulfate application. Both rice straw and aluminum sulfate applications could reduce the humification degree of free and combined fraction of HA. According to the types of HA, it could be concluded that humus became younger and renewed due to the application of rice straw and aluminum sulfate.

The role of dissolved organic carbon concentration and composition on nickel toxicity to early life-stages of the blue mussel Mytilus edulis and purple sea urchin Strongylocentrotus purpuratus.

Nickel (Ni) emissions resulting from production and transportation raise concerns about the impact of Ni exposure to marine ecosystems. Ni bioavailability models are established for FW systems, but the influence of chemical parameters (e.g. dissolved organic carbon (DOC)) on Ni toxicity within marine systems is less well understood. To examine the effects of DOC concentration and composition on Ni toxicity, acute toxicity tests were conducted on early life-stages of blue mussels (Mytilus edulis) and sea urchin embryos (Strongylocentrotus purpuratus) in full strength sea water (32 ppt). Nine different field collected samples of water with varying concentration (up to 4.5 mg C/L) and composition of DOC were collected from the east coast of the United States. Organic matter compositional analysis included molecular fluorescence and absorbance spectroscopy. The different DOC sources had different protective effects against embryo toxicity. The control (no DOC) Ni 48 h-EC50 for Mytilus embryos was 133 µg/L (95% confidence interval (C.I.) of 123-144 µg/L), while Strongylocentrotus embryos displayed control 96-h EC50 values of 207 µg/L (167-247 µg/L). The most significantly protective sample had high humic acid concentrations (as determined from fluorescence spectroscopy), which yielded an EC50 of 195 µg/L (169-222 µg/L) for Mytilus, and an EC50 of 394 µg/L (369-419 µg/L) for S. purpuratus. Among all samples, protection was related to both DOC quantity and quality, with fluorescence-resolved humic and fulvic acid concentrations showing the strongest correlations with protection for both species. These data suggest that DOC is protective against Ni toxicity in M. edulis and S. purpuratus, and that accounting for a DOC quality factor will improve predictive toxicity models such as the biotic ligand model.

Application of metabolomics profiling in the analysis of metabolites and taste quality in different subtypes of white tea.

Three subtypes of white tea, Silver Needle (SN), White Peony (WP), and Shou Mei (SM), differ in their taste, aroma, bioactivity, and commercial value. Here, a metabolomics investigation on the chemical compositions combining taste equivalent-quantification and dose-over-threshold (DoT) determination on the taste qualities were applied to comprehensively characterize the white tea subtypes for the first time. Significant differences in the contents of catechins, dimeric catechins, amino acids, phenolic acids, flavonol/flavone glycosides, and aroma precursors were observed among these 3 white teas. Metabolite content comparison and partial least-squares (PLS) analysis suggest that theanine, aspartic acid, asparagine, and AMP were positively correlated with the umami taste in white tea, and flavan-3-ols, theasinensins, procyanidin B3, and theobromine had positive correlations with higher bitterness and astringency tastes. In addition, puckering astringent (-)-epigallocatechin gallate (EGCG), (-)-epicatechin gallate (ECG) and theogallin, bitter-tasting caffeine, and the mouth-drying/velvety-like astringent γ-aminobutyric acid (GABA) were identified as key taste compounds of white tea infusion by absolute quantification and DoT factor calculations. This work provided systematic and comprehensive knowledge on the chemical components, taste qualities, and sensory active metabolites for the subtypes of white tea.

An emerging strategy for evaluating the grades of Keemun black tea by combinatory liquid chromatography-Orbitrap mass spectrometry-based untargeted metabolomics and inhibition effects on α-glucosidase and α-amylase.

Quantitative analysis and untargeted liquid chromatography mass spectrum (LC-MS) based metabolomics of different grades of Keemun black tea (KBT) were conducted. Quantitative analysis did not show tight correlation between tea grades and contents of polyphenols, but untargeted metabolomics analysis revealed that high-grades KBT were distinguished from the low-grades. S-plot and Variable Importance (VIP) analysis gave 28 marker compounds responsible for the discrimination of different grades of KBT. The inhibitory effects of KBT on α-amylase and α-glucosidase were positively correlated to tea grades, and the correlation coefficient between each marker compound and inhibitory rate were calculated. Thirteen compounds were positively related to the anti-glycemic activity, and theasinensin A, afzelechin gallate and kaempferol-glucoside were confirmed as grade-related bioactive marker compounds by chemical and bioassay in effective fractions. This study suggested that combinatory metabolomics and bioactivities assay provided a new strategy for the classification of tea grades.

Hypersaline sapropels act as hotspots for microbial dark matter.

Present-day terrestrial analogue sites are crucial ground truth proxies for studying life in geochemical conditions close to those assumed to be present on early Earth or inferred to exist on other celestial bodies (e.g. Mars, Europa). Although hypersaline sapropels are border-of-life habitats with moderate occurrence, their microbiological and physicochemical characterization lags behind. Here, we study the diversity of life under low water activity by describing the prokaryotic communities from two disparate hypersaline sapropels (Transylvanian Basin, Romania) in relation to geochemical milieu and pore water chemistry, while inferring their role in carbon cycling by matching taxa to known taxon-specific biogeochemical functions. The polyphasic approach combined deep coverage SSU rRNA gene amplicon sequencing and bioinformatics with RT-qPCR and physicochemical investigations. We found that sapropels developed an analogous elemental milieu and harbored prokaryotes affiliated with fifty-nine phyla, among which the most abundant were Proteobacteria, Bacteroidetes and Chloroflexi. Containing thirty-two candidate divisions and possibly undocumented prokaryotic lineages, the hypersaline sapropels were found to accommodate one of the most diverse and novel ecosystems reported to date and may contribute to completing the phylogenetic branching of the tree of life.

Benefits of multidimensional fractionation for the study and characterization of natural organic matter.

The belief that chromatographic separation of complex environmental mixtures or natural organic matter (NOM) produces featureless humps from which little, if anything, can be learned is still pervasive. Meanwhile improvements in chromatography and the use of information-rich detection methods have led to meaningful fractionation and revealed consistent data. Here, we build on this work and developed a robust, facile two-dimensional separation with high orthogonality between dimensions. We illustrate that re-injections of fractions (both in the first and in the second dimension) leads to individual peaks at the expected retention times and use information-rich detection to investigate the basis on which NOM is fractionated. We demonstrate unprecedentedly feature-rich chromatograms are observed even with standard UV detection for polar NOM fractions. The second stage of fractionation is demonstrated to separate isomers, providing a direct look at isomeric complexity in NOM as well as a tool to reduce it. Consistent with expectation, but confirmed for the first time through mass spectral data, radicals were detected for NOM components that were generally nonpolar and grouped in the condensed aromatic structure - like region of van Krevelen plots. High-resolution tandem mass spectral data, furthermore, suggests that many higher-MW components of fulvic acids (especially the highly oxidized ones) have formulas that do not match any known compounds in the literature, supporting the hypothesis that fulvic acids are a unique compound-class. Combined, the data illustrate that meaningful reduction in complexity reveals new compositional and structural detail and avails new avenues of investigation.

Dihydromunduletone Is a Small-Molecule Selective Adhesion G Protein-Coupled Receptor Antagonist.

Adhesion G protein-coupled receptors (aGPCRs) have emerging roles in development and tissue maintenance and is the most prevalent GPCR subclass mutated in human cancers, but to date, no drugs have been developed to target them in any disease. aGPCR extracellular domains contain a conserved subdomain that mediates self-cleavage proximal to the start of the 7-transmembrane domain (7TM). The two receptor protomers, extracellular domain and amino terminal fragment (NTF), and the 7TM or C-terminal fragment remain noncovalently bound at the plasma membrane in a low-activity state. We recently demonstrated that NTF dissociation liberates the 7TM N-terminal stalk, which acts as a tethered-peptide agonist permitting receptor-dependent heterotrimeric G protein activation. In many cases, natural aGPCR ligands are extracellular matrix proteins that dissociate the NTF to reveal the tethered agonist. Given the perceived difficulty in modifying extracellular matrix proteins to create aGPCR probes, we developed a serum response element (SRE)-luciferase-based screening approach to identify GPR56/ADGRG1 small-molecule inhibitors. A 2000-compound library comprising known drugs and natural products was screened for GPR56-dependent SRE activation inhibitors that did not inhibit constitutively active Gα13-dependent SRE activation. Dihydromunduletone (DHM), a rotenoid derivative, was validated using cell-free aGPCR/heterotrimeric G protein guanosine 5'-3-O-(thio)triphosphate binding reconstitution assays. DHM inhibited GPR56 and GPR114/ADGRG5, which have similar tethered agonists, but not the aGPCR GPR110/ADGRF1, M3 muscarinic acetylcholine, or ß2 adrenergic GPCRs. DHM inhibited tethered peptide agonist-stimulated and synthetic peptide agonist-stimulated GPR56 but did not inhibit basal activity, demonstrating that it antagonizes the peptide agonist. DHM is a novel aGPCR antagonist and potentially useful chemical probe that may be developed as a future aGPCR therapeutic.

Cadmium availability and uptake by radish (Raphanus sativus) grown in soils applied with wheat straw or composted pig manure.

Soil cadmium (Cd) availability and uptake by cherry-red radish (Raphanus sativus) grown in Cd-contaminated soils after addition with wheat straw or composted pig manure were studied. The results indicated that wheat straw application promoted radish growth until the second harvest, while pig manure application improved radish biomass in Acid Ferralsols regardless of harvesting seasons. Application with pig manure might be more effective in lowering the Cd uptake by radish than wheat straw. Especially when pig manure of 11.9 g TOC kg(-1) amended into Acid Ferralsols, Cd contents in leaves and roots of radish decreased by 89.2 and 95.7 % at the second harvest, respectively. The changes in Cd fractions distribution in soils after application were contributed to the decline of Cd availability. Furthermore, significantly negative linear correlation (P < 0.05) between the ratio of humic acid (HA) and fulvic acid (FA) in soils and exchangeable Cd was also observed. However, the significantly negative relationship (P < 0.01) between soil pH and exchangeable Cd was merely found in pig manure-treated Acid Ferralsols. The increases in HA/FA ratio or pH values in soils after adding organic materials were also responsible for the decrease of Cd availability in soils and uptake by radish. Thus, it is recommended to stabilize soil Cd and reducing plant uptake by application with composted manure without or slightly contaminated with metals.

Oil Recovery from Water under Environmentally Relevant Conditions Using Magnetic Nanoparticles.

Large oil spills and oily wastewater discharges from ships and industrial activities can have serious impacts on the environment with potentially major economic impacts. Current oil remediation techniques are inefficient and may have deleterious environmental consequences. However, nanotechnology offers a new route to potentially remediate oil pollution. In this study, a cheap and facile hydrothermal method was developed to synthesize polyvinylpyrrolidone-coated magnetite nanoparticles to separate a reference MC252 oil from oil-water mixture under environmentally relevant conditions. Fluorescence and Proton nuclear magnetic resonance spectroscopy results showed near 100% oil removal from oil-water mixture in the ultrapure water under optimum condition. Based on gas chromatography-mass spectrometry data, approximately 100% of lower molecular mass alkanes (C9-C21) were removed within 10 min of magnetic separation and by increasing the separation time to 40 min, greater than 67% of C22-25 alkanes were removed. Moreover, nanoparticles removed near 100% oil from synthetic seawater solutions in the presence and absence of fulvic acid showing excellent oil removal capacity of the nanoparticles under different conditions. Results show that these nanoparticles can be utilized to remove oil over a short time with a high removal efficiency under environmentally relevant conditions.

Plutonium(IV) sorption to montmorillonite in the presence of organic matter.

The effect of altering the order of addition in a ternary system of plutonium(IV), organic matter (fulvic acid, humic acid and desferrioxamine B), and montmorillonite was investigated. A decrease in Pu(IV) sorption to montmorillonite in the presence of fulvic and humic acid relative to the binary Pu-montmorillonite system, is attributed to strong organic aqueous complex formation with aqueous Pu(IV). No dependence on the order of addition was observed. In contrast, in the system where Pu(IV) was equilibrated with desferrioxamine B (DFOB) prior to addition of montmorillonite, an increase in Pu(IV) sorption was observed relative to the binary system. When DFOB was equilibrated with montmorillonite prior to addition of Pu(IV), Pu(IV) sorption was equivalent to the binary system. X-ray diffraction and transmission electron microscopy revealed that DFOB accumulated in the interlayer of montmorillonite. The order of DFOB addition plays an important role in the observed sorption/desorption behavior of Pu. The irreversible nature of DFOB accumulation in the montmorillonite interlayer leads to an apparent dependence of Pu sorption on the order of addition in the ternary system. This work demonstrates that the order of addition will be relevant in ternary systems in which at least one component exhibits irreversible sorption behavior.

Monitoring of sixteen fragrance allergens and two polycyclic musks in wastewater treatment plants by solid phase microextraction coupled to gas chromatography.

A methodology based on headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) determination was developed for the monitoring and evaluation of the removal efficiency of 16 common fragrance allergens and two polycyclic musks in wastewater treatment plants (WWTPs). An experimental design with a full factorial model was applied to evaluate the effects of the experimental parameters on the extraction (e.g., salt content, time and extraction temperature). After determining the optimum conditions (2.4 g NaCl, 45 min at 90 °C), an external calibration was performed and quality parameters of the proposed method were evaluated. Method detection limits in the range of 0.01-1.7 µg L(-1) were obtained. Satisfactory inter-day precision values between 4% and 23% (n=5) were obtained for most compounds. The method was applied to the monitoring of the target analytes in samples from two WWTPs. Seven target compounds were detected at the primary effluent of both plants at µg L(-1) levels. Limonene, linalool and eugenol were quantitatively eliminated during the secondary treatments of both WWTPs, while lilial, benzyl salicylate, galaxolide, and tonalide were still detected at the effluent waters.

Identification of novel homologous series of polyhydroxylated theasinensins and theanaphthoquinones in the SII fraction of black tea thearubigins using ESI/HPLC tandem mass spectrometry.

Thearubigins are the most abundant phenolic pigments found in black tea, produced by enzymatic oxidation of green tea flavan-3-ols in tea fermentation of until recently unknown composition. In this study electrospray ionization tandem LC-MS(n) experiments have been applied for the characterization of crude thearubigins isolated from black tea not exceeding 1000 Da. The aim of this study is to confirm the oxidative cascade hypothesis of tea fermentation. The data revealed the presence of two novel classes of compounds in thearubigin fractions. The first class of compounds revealed the presence of polyhydroxylated dimers of the theanaphthaquinone and theasinensin C structures, which were consistent with the polyhydroxylation hypothesis previously formulated. Furthermore, new classes of peroxo-/epoxy- compounds in the series of theasinensin A were identified, thus indicating the presence of H2O2 and its important contribution as a nucleophile in the tea fermentation process.