Hydrophilic Fraction Research Articles

Phytochemical characterization of phloem in maritime pine and stone pine in three sites in Portugal

This study analyzes the content and chemical profile of extractives present in the young phloem of mature trees of maritime pine (Pinus pinaster) and stone pine (P. pinea) in three sites in Portugal located in different climatic environments.The cross-sites average of extractives was similar in both pines with 38.5% in P. pinea and 37.7% in P. pinaster phloem. The hydrophilic fraction represented 82% and 70% of P. pinea and P. pinaster total extractives respectively, with large contents of phenolic compounds, flavonoids and tannins, and showed very high oxygen scavenging and reducing ability. Lipophilic extractives were present in higher proportion in P. pinaster phloem than in P. pinea phloem, and showed a large content of resin acids, with the predominance of abietic acid in P. pinaster, and dehydroabietic acid in P. pinea phloems, and of alkanoic acids.P. pinaster and P. pinea have specific defences related to phloem production of resin and phenolic compounds with the ratio phenolic-to-oleoresin compounds higher for P. pinea (4.7 vs 2.3 for P. pinaster) and constant in the three sites. The phytochemical content and composition of the young phloem of P. pinaster and P. pinea showed site differences highlighting the relationship between environment and metabolic production.

Modification of regenerated cellulose ultrafiltration membranes with multi-walled carbon nanotubes for enhanced antifouling ability: Field test and mechanism study.

Although ultrafiltration (UF) has been extensively employed for drinking water purification, it is crucial to further develop novel membrane materials to improve the antifouling capacity and satisfy the practical usage. Multi-walled carbon nanotubes (MWCNTs) have characteristics that could potentially improve the membrane antifouling performance. Therefore, in this study, modified cellulose UF membranes were prepared using MWCNTs of various outer diameters ranging from 10 to 20nm to 40-60nm. The antifouling properties of the modified membrane and natural organic matter (NOM) removal mechanism were investigated while treating water from a local drinking water source river. Overall, the antifouling ability increased by more than one-fold when the nascent cellulose membrane was coated with MWCNTs (outer diameter of 40-60nm) at a loading of 17.4g/m2. The molecular weight distribution profiles of the NOM in the raw water and permeates suggest the superior performance of the modified membranes in removing two major NOM fractions with molecular weights ranging from approximately 5k-30k and 500k-1000k. Based on its hydrophobicity, the NOM of the raw water was fractionated into the strong hydrophobic (SHPO), the weak hydrophobic, the strong hydrophilic and the moderately hydrophilic (MHPI) fractions. The WHPO fraction caused the highest fouling compared with the other fractions under consistent experimental conditions. Meanwhile, the modified membranes showed a preference for removing the MHPI and SHPO fractions. These results imply that MWCNTs can be employed to improve the antifouling property of cellulose UF membranes and have the potential to selectively remove moderately hydrophilic contaminants from water.

Sequence of supercritical CO2 extraction and subcritical H2O extraction for the separation of tobacco waste into lipophilic and hydrophilic fractions

A tobacco solid waste was extracted by a sequence of supercritical CO2 (SC-CO2) extraction and subcritical water extraction (SWE). The tobacco waste lipophilic compounds (targeted fatty acids, free base nicotine and VOCs) were extracted using the series of the main operation parameters for the SC-CO2 extraction (pressure: 100–300bar, temperature: 40–80°C). The obtained SC-CO2 extracts were rich in nicotine (0.362–1.585%), neophytadiene (0.082–0.256%) and 4,8,13-duvatriene-1,3-diol (0.144–0.590%). Other VOCs and targeted fatty acids (palmitic, stearic, oleic, linoleic and linolenic) were also determined. Optimized condition for the SC-CO2 extraction of tobacco waste was found at 300bar and 61.22°C. The residues (after SC-CO2 extraction) were re-extracted with SWE under the solvent/solid ratio: 28mL/g, temperature: 150°C, time: 23min. SWE extracts (hydrophilic fractions) were characterized by high concentrations of nicotine (1.61–4.67%), nicotinamide (0.198–0.428%), nicotinic acid (0.118–0.239%), phenolic compounds: chlorogenic acid (0.458–0.740%), 3,4-dihydroxybenzoic acid (0.236–0.403%), neochlorogenic acid (0.240–0.534%), and rutin (0–1.025%). They contained total phenols in the amount 8.03–10.11% and exhibited DPPH antiradical scavenging activity in the range 77.89 to 93.35%. As the results of applied higher temperature 5-HMF (0.076–0.11%), furfural (0.510–0.740%) and 5-MF (0.0292–0.0453%) were also detected in SWE extracts. In some experiments, the obtained values of detected compounds were considerable higher than those obtained from the raw scrap (without SC-CO2 extraction pretreatment) implying that two-stage extraction process (SC-CO2 extraction followed by SWE) can enhance the extraction efficiency due to the elimination of fats during SC-CO2 extraction which enables better dissolution of the other compounds in subcritical H2O.

Composition and Antioxidant Activity, Supercritical Carbon Dioxide Extraction Extracts, and Residue after Extraction of Biologically Active Compounds from Freeze-Dried Tomato Matrix

Supercritical carbon dioxide extraction (SCE-CO2) is an attractive, green technology that is used for the recovery of biologically active compounds from plant material. The antioxidant potential of lipophilic fractions (extract obtained with SCE-CO2) and hydrophilic fractions (extracts obtained from the residue after extraction) obtained from a matrix of freeze-dried tomatoes (cvs. “Admiro” F1, “Jurgiai”, “Vilina”, “Pirmutis”, and “Skariai”) was assessed via different antioxidant activity methods. The total amount of polyphenols, carotenoids, and carotenoid isomers before and after SCE-CO2 extraction was also determined. To investigate the effect of the SCE-CO2 extract on the viability of cancer cells, rat glioblastoma C6 cells were chosen. The SCE-CO2 yielded an average of 800 mg of lipophilic fraction per 100 g of freeze-dried tomatoes. The ABTS•+ scavenging activity of the extract was 251 ± 3.4 µmol TE/g. After SCE-CO2 extraction, the DPPH•-RSA of the freeze-dried tomato matrix was 7 to 12% higher. There was a strong positive correlation (R = 0.84) between the total polyphenolics content and the DPPH•-RSA of the tomato samples. The SCE-CO2 increased the radical scavenging activity of the extraction residue, indicating that a considerable fraction of the hydrophilic compounds with particular antioxidant capacity remain unextracted from the tomato matrix. Our results reveal the cytotoxic effect of lycopene extract rich in cis-isomers (62% cis-isomers of the total lycopene content) on rat glioblastoma C6 cells. The viability of the glioblastoma C6 cells significantly decreased (−42%) at a total lycopene concentration of 2.4 µM after 24 h of incubation.

Characteristics of trihalomethane and haloacetic acid precursors in filter backwash and sedimentation sludge waters during drinking water treatment

Trihalomethanes (THMs) and haloacetic acids (HAAs) are the most common disinfection byproducts posing human health risks. This study investigated the precursors of THMs and HAAs in filter backwash water (FBW) and sedimentation sludge water (SSW) by the methods of ultrafiltration membranes, synthetic resins and excitation-emission matrix (EEM) spectra. The concentrations of dissolved organic carbon (DOC) in FBW and SSW ranged from 1.7 to 2.7 mg/L and 2.7 to 5.8 mg/L, respectively. After chlorination, THMs and HAAs ranging from 223 to 608 μg/L and 26 to 110 μg/L were generated in FBW and SSW, respectively. There were more THM precursors than HAAs in FBW and SSW, but the formation of HAAs was often affected by water quality in terms of DOC, specific ultraviolet absorbance (SUVA), etc. High concentrations of bromo-trihalomethanes (Br-THMs) were generated in FBW and SSW, while monochloroacetic acid (MCAA) was the dominant species. The effect of bromide concentration on the formation of total THMs was greater than that of HAAs. Fluorescence analysis revealed that aromatic protein-like compounds were the dominant dissolved organic matter (DOM) in FBW and SSW. The concentrations of THMs and HAAs in the MW < 3 kDa fraction accounted for 58–80% and 62–74% of the whole sample, respectively. Hydrophilic (HPI) organic matter with molecular weight (MW) < 3 kDa was the main precursor of THMs and HAAs in FBW and SSW. Both HPI and hydrophobic (HPO) fractions were proven to play a considerable role in the formation of HAAs. Therefore, the corresponding treatment strategies should be considered to remove low-MW, HPI and HPO organics according to the water quality of FBW and SSW before recycling in order to avoid the formation of THMs and HAAs.

Effect of Fe-based catalytic ozonation and sole ozonation on the characteristics and conversion of organic fractions in bio-treated industrial wastewater

The conversion of hydrophobic (HPO)/transphilic (TPI)/hydrophilic (HPI) fractions of dissolved effluent organic matter (EfOM) in water by sole ozonation process (SOP) and catalytic ozonation process (COP) were investigated in this study. The modified iron shavings were used as catalyst in COP. The difference in total organic carbon (TOC) removal rate between SOP and COP for two types of bio-treated industrial wastewater was mainly caused by the different HPI degradation degree. The accumulation of HPI in SOP was 28.8% (in bio-treated dyeing wastewater) and 88.8% (in bio-treated paper-making wastewater) higher than that in COP, while HPO was degraded by more than 90% in both processes. Part of HPO was converted to TPI in the early stage (0–15 min) and the original HPI in the raw water was degraded at the same time. In the middle stage (15–60 min), TPI was transformed into HPI. The remaining fluorescent substances in HPI fraction in SOP were higher than those in COP, indicating that more HPI was accumulated in SOP. Among the fluorescent substances, aromatic protein II and SMP-like substances were removed more completely, while humic acid-like substances were relatively more difficult to degrade. Furthermore, COP had higher removal for fulvic acid-like substances, SMP-like substances and humic acid-like substances than SOP, while the removals of aromatic protein by COP and SOP were almost the same. COP had better removal effect than SOP for TPI and HPI organic pollutants with molecular weight (MW) more than 2 kDa. SOP and COP had no significant difference in the removal of HPO fraction and small molecular organics with MW less than 2 kDa. The remaining organic pollutants in the effluent of COP was mainly hydrophilic small molecular substances, which would be benefit for secondary biochemical process.

Hydrophobic Fractions of Triticum aestivum L. Extracts Contain Polyphenols and Alleviate Inflammation by Regulating Nuclear Factor-kappa B

As a nutritional supplement, wheatgrass (Triticum aestivum L.) is well-known for its anti-inflammatory effects that are exerted through signal transduction pathways. Wheatgrass was extracted in 80% ethanol (WGE), and the ethanol extracts were further fractionated using ethyl acetate, n-butanol, and water. To determine the antioxidant activity, WGE was tested using various radical-scavenging assays. To explain the anti-inflammatory mechanisms, western blotting, reverse-transcription polymerase chain reaction, luciferase assay, immunofluorescence staining, and the inhibition of mitogen-activated protein kinase (MAPK) phosphorylation were performed using mouse macrophage cells (RAW 264.7). Inhibition of proinflammatory and Th2 cytokines was analyzed using a 2,4-dinitrochlorobenzene-induced contact dermatitis mouse model. WGE exhibited a strong antioxidant activity in radical scavenging-assays conducted using artificial and natural substrates. The ethyl acetate and n-butanol fractions (hydrophobic fractions) obtained from the 80% ethanolic extract, inhibited the expression of inducible nitric oxide synthase gene, whereas the aqueous layer (the hydrophilic fraction) showed no inhibitory effects. In addition, the hydrophobic fractions inhibited nuclear factor-kappa B (NF-κB) and reduced phosphorylation of MAPK, indicating that inflammation was alleviated possibly by the regulation of NF-κB signaling. This mechanism was further elucidated using the RAW 264.7 cell line and mouse model. Using high-performance liquid chromatography, the hydrophobic fractions were separated into over 10 phenolic compounds, among which benzoic acid, quercetin, and luteolin were abundant. The study demonstrated that wheatgrass is a potential nutraceutical candidate with antioxidant and anti-inflammatory properties for future use in health foods and cosmetics.

Assessment of oxidative potential by hydrophilic and hydrophobic fractions of water-soluble PM2.5 and their mixture effects.

Transition metals (TMs) (e.g. copper (Cu) and iron (Fe)) and certain organic compounds are known active constituents causing oxidative potential (OP) by inhaled ambient fine particulate matter (PM2.5) in lung fluid. Humic-like substances (HULIS), isolated from atmospheric PM2.5, are largely metal-free and contain mixtures of organics that are capable of complexing TMs. TMs and HULIS co-exist in the water-extractable part of PM2.5. In this work, we used a solid phase extraction procedure to isolate the water-soluble TMs in the hydrophilic fraction (HPI) and HULIS in the hydrophobic fraction (HPO) and carried out this isolation procedure to a set of 32 real-world PM2.5 samples collected in Beijing and Hong Kong, China. We quantified two OP endpoints, namely hydroxyl radical formation (denoted as OP•OH) and ascorbic acid depletion (denoted as OPAA), by the two fractions separately and combined, as well as by the bulk water-soluble aerosols. OP•OH and OPAA were well-correlated in both separate fractions and their combined mixtures or bulk water-soluble aerosols. OP by HPI far exceeded that by HPO. On a per unit PM2.5 mass basis, the Hong Kong samples on average had a higher OPAA and OP•OH than the Beijing samples due to more water-soluble Cu. For HPI, Cu was a dominant OP•OH and OPAA contributor (>80%), although water-soluble Fe was present at a concentration approximately one order of magnitude higher. Suppression effects on OP•OH were observed through comparing the OP of the bulk water-soluble aerosol with that of HPI. Our work reveals the importance of monitoring PM2.5 chemical compositions (especially water-soluble redox active metals). Furthermore, we demonstrate the need to consider metal-organic interactions when evaluating the aggregate OP by PM2.5 from individual components or apportioning OP by PM2.5 to specific chemical components.

Effects of surface heterogeneities on wetting and contact line dynamics as observed with the captive bubble technique

Understanding the effects of surface heterogeneities on wetting characteristics and contact line dynamics is significant for a number of applications. In this work, the advancing and receding contact angles on well-defined heterogeneous surfaces were measured using the captive bubble technique. Furthermore, contact line distortions were observed to clarify the origin of the changes in the contact angle. For heterogeneous surfaces with different hydrophilic area fractions but the same hydrophilic defect diameter, the defects had no restrictive effect on the retreating behavior of the contact line, resulting in a nearly constant advancing contact angle. Conversely, during receding contact angle measurements, the presence of a few hydrophilic defects caused three-phase contact line pinning. Increasing the number of hydrophilic defects led to more corrugations of the three-phase contact line, resulting in a decrease in the receding contact angle. For heterogeneous surfaces with the same hydrophilic area fraction but different hydrophilic defect diameters, the advancing contact angles were also nearly constant because in the hydrophilic region, no energy barrier prevented contact line movement. However, the greater energy barriers caused by larger hydrophilic defects led to a slight decrease in the receding contact angles. A comparison of the measured and calculated values for both the advancing and receding contact angles showed that the experimental contact angle results were consistent with the contact angles calculated using the line-fraction Cassie equation. These insights into the wetting behavior of heterogeneous surfaces under liquids are expected to lead to advanced practical applications of heterogeneous surfaces.

Size and resin fractionations of dissolved organic matter and characteristics of disinfection by-product precursors in a pilot-scale constructed wetland

Abstract Controlling the formation of disinfection by-products (DBPs) is a major issue in the drinking water industry, and understanding the characteristics of DBP precursors in treatment processes for micro-polluted raw water is key to improving water quality. In this study, a sampling program was undertaken to investigate the fate of dissolved organic matter (DOM) and the characteristics of DBP precursors in a pilot constructed wetland imitating the Yanlong Lake ecological project. Using XAD resin adsorption and ultrafiltration techniques, the dissolved organic carbon, UV254, and DBP formation potential (DBPFP) were measured in different DOM fractions in raw water and wetland effluents. After the constructed wetland treatment, the low molecular weight fraction (&amp;lt;3 kDa) of DOM and DBPFP generally showed a decreasing trend along the water path, while the high molecular weight fraction (&amp;gt;3 kDa) of DOM increased. The specific DBPFP (SDBPFP) was much higher in the &amp;lt;1 kDa fraction than in the other fractions. Although the hydrophobic fraction of DOM was the most abundant in all stages of the wetland treatment, the SDBPFP of the hydrophilic fraction was higher than that of the hydrophobic fraction. Furthermore, compared with raw water, the DOC, UV254 and DBPFP in the treated wetland effluents increased; however, all of the chemical DOM fractions exhibited decreased SDBPFP in accordance with a decrease in the specific ultraviolet absorbance during wetland treatment. These conclusions indicate that the DOM produced by the wetland system may generate DBPs less readily compared with the DOM of raw water.

Physicochemical and Antioxidant Capacity of Jujube (Ziziphus jujuba Mill.) at Different Maturation Stages

Jujube is a crop very resistant to drought and salinity, making it an interesting growing alternative in southeastern Spain. The characteristics of five different cultivars of the jujube fruit have been evaluated and classified into four different maturation stages according to the color of the peel, ranging from green in its most immature stage, to white, yellow, and red in its last, more mature stage. This is due in part to the amount of carotenoids and chlorophylls studied, which vary as the fruit matures. The cultivars ‘GAL-E’ and ‘GAL-T’ are the largest in size and weight, followed by ‘MSI’, ‘PSI’, and ‘DAT’, which are the smallest cultivars. The content of phenolic compounds was also analyzed. The antioxidant activity, which was studied by different methods, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and ferric reducing antioxidant power (FRAP), showed the highest activity in stages 3 and 4 of jujube fruit. The antioxidant activity studied in the hydrophilic and lipophilic fraction by the ABTS method showed the highest peak in stages 1 and 2. This is an important information to know promising cultivars to be used in future breeding programs. Moreover, the maturation stage is relevant to obtain fruit with a high content of bioactive compounds as well as interesting organoleptic properties.

Impact of Ozone Used-Alone and Coagulation Aid Treatment on The Reduction of Trihalomethanes Components

The whole research paper examines the impact of ozone as either a just use-alone and coagulation benefit, mainly upon the reduction of dissolved organic carbon from the water with a moderate rate of DOC 10.75 mg/land CaCO3 calcium hardness 300 mg/l. A raw water sample has been taken from the Tigris River (Baghdad, Iraq) was being adopted in research work. The performance of ozone therapy has been assessed by calculations of DOC, DOC quantities, UV254, as well as total trihalomethane (TTHM). Research findings have shown that with 0.9 mg O3/mg DOC ozone use-alone, approximately 60% UV254 reduction and approximately 28% DOC reduction will occur.DOC fractionation analysis indicates that within the water samples, ozone could alter the composition of DOC, transform the hydrophobic fractions toward hydrophilic fractions and reduce TTHM. Ozone was also responsible for a significant reduction in particle stability as well as the dissolved calcium content. Improved water flocculation and improved DOC removal were triggered by these simultaneous ozonation effects. This resulted in a decrease in the coagulant dosage while the dosage of ozone is considerably higher over 0.3 mg O3/mg DOC has added before ferric sulfate coagulation. The pre-ozonation coagulation method also accomplished favorable removal of TTHM with all tested ozone doses (0 to 0.9 mg O3/mg DOC), resulting in lower TTHM during pre-ozonated coagulated waters unlike those through related ozonated waters.

Стандартизация сухого экстракта сока мякоти тыквы, обладающего гиполипидемическим действием по содержанию β-каротина

The objective is to standardize the content of β-carotene – one of the principal active substances with sufficient hypolipidemic activity in the resultant original product. Search for natural biologically active substances having a hypolipidemic effect is one of the topical questions in modern pharmacy. Most of the research is carried out by means of isolating individual substances from the plant object. We propose to study a native phytocomplex obtained from pumpkin pulp – a dry extract of pumpkin pulp juice. The following materials and methods were used: laboratory-obtained dry extract of pumpkin pulp juice and methods used to determine the qualitative and quantitative content of β-carotene in an individual substance. It was possible to adapt the methods applied to the analysis of an individual substance in relation to the resulting phytocomplex containing both lipophilic and hydrophilic fractions. The rapid method of quantitative determination of β-carotene described in the scientific literature was corrected. An effective alternative method for spectrophotometric determination of β-carotene in the phytocomplex has been developed. Phytocomplexes standardized for the main active substances can be used to obtain effective drugs and biologically active additives with minimal side effects. In addition, the expansion of the search for alternative natural objects containing complexes haaving a hypolipidemic effect is currently relevant. Based on the literature data, in the future it is planned to conduct a pharmacological study to establish the anti-inflammatory effect of the resulting complex on the state of the vascular wall.

A novel dipeptide derived from porcine liver hydrolysate induces recovery from physical fatigue in a mouse model

Abstract The present study was conducted to identify anti-fatigue peptides in porcine liver hydrolysate (LH) and to evaluate their effects. Peptides in LH were fractionated into hydrophilic and hydrophobic fractions and further into peptides with amino groups (Pep-NH2) and pyroglutamyl peptide fractions (pE). Low dose of hydrophobic Pep-NH2 fraction reversed the decrease in locomotor activity after forced walking in a mouse model upon intraperitoneal (i.p.) administration. The anti-fatigue effects of i.p. injection of Asp-Val, Asp-Leu, and Asp-Phe with α and β peptide bonds and D- and L- asparatyl residue, which appeared in blood after oral administration of LH, were examined. In particular, Asp-Leu (Lβ), Asp-Phe (Dα), and Asp-Phe (Lα) exerted anti-fatigue effects at a low concentration (0.03 mg/kg). We found that Asp-Phe (Lα), but not other dipeptides, activated adenosine monophosphate-activated protein kinase (AMPK) in the liver, indicating that Asp-Phe (Lα) could induce recovery from fatigue via AMPK activation.

The in vitro and in vivo wound-healing effects of royal jelly derived from Apis mellifera L. during blossom seasons of Castanea mollissima Bl. and Brassica napus L. in South China exhibited distinct patterns

BackgroundNon-healing wounds have been a severe issue in the global healthcare system. Regrettably, royal jelly, a traditional remedy for various skin injuries, has not been widely applied in cutaneous wounds in clinical practice nowadays, which may be due to the confusion and the lack of knowledge about the efficacies of different types of royal jelly, the bioactive constituents, and the precise mechanisms underlying the wound repairing activity. Since the compositions and bioactivities of royal jelly are predominantly influenced by nectar plants, this study aims to explore the differences in the wound-healing properties of royal jelly produced by Apis mellifera L. during the blossom seasons of different floral sources, to provide guidelines for the future rational application of royal jelly in cutaneous wounds, and to promote the further discovery of wound repair-promoting substances.MethodsRoyal jelly samples were harvested during flowering seasons of Castanea mollissima Bl. (chestnut) and Brassica napus L. (rapeseed) in South China, from which hydrophilic and lipophilic fractions were extracted. The in vivo wound-healing potential was preliminarily assessed in Wistar rats’ excisional full-thickness wounds, followed by investigating the mechanisms of action through in vitro assays with human epidermal keratinocytes and LPS-stimulated inflammation in macrophages.ResultsThe results indicated that different royal jelly samples exhibited distinct wound-healing potential, in which Castanea mollissima Bl. royal jelly was more potent. It sped up wound closure between day 2 and day 4 to 0.25 cm2/day (p < 0.05), and could accelerate wound repair by enhancing the proliferative and migratory capabilities of keratinocytes by 50.9% (p < 0.001) and 14.9% (p < 0.001), modulating inflammation through inhibiting nitric oxide production by 46.2% (p < 0.001), and promoting cell growth through increasing the secretion of transforming growth factor-β by 44.7% (p < 0.001). In contrast, Brassica napus L. royal jelly could regulate inflammation by reducing the amount of tumour necrosis factor-α by 21.3% (p < 0.001).ConclusionsThe present study improves the application of royal jelly for curing difficult-to-heal wounds, in which the hydrosoluble extract of Castanea mollissima Bl. royal jelly promises the greatest potential. It also provides clues which may lead towards the identification of substances derived from royal jelly to treat wounds.

An Updated Perspective on Sinorhizobium meliloti Chemotaxis to Alfalfa Flavonoids.

The symbiotic interaction between leguminous plants and their cognate rhizobia allows for the fixation of gaseous dinitrogen into bioavailable ammonia. The perception of host-derived flavonoids is a key initial step for the signaling events that must occur preceding the formation of the nitrogen-fixing organ. Past work investigating chemotaxis – the directed movement of bacteria through chemical gradients – of Bradyrhizobium japonicum, Rhizobium leguminosarum, and Rhizobium meliloti discovered chemotaxis to various organic compounds, but focused on chemotaxis to flavonoids because of their relevance to the symbiosis biochemistry. The current work sought to replicate and further examine Sinorhizobium (Ensifer) meliloti chemotaxis to the flavonoids previously thought to act as the principal attractant molecules prior to the initial signaling stage. Exudate from germinating alfalfa seedlings was analyzed for composition and quantities of different flavonoid compounds using mass spectrometry. The abundance of four prevalent flavonoids in germinating alfalfa seed exudates (SEs) was at a ratio of 200:5:5:1 for hyperoside, luteolin, luteolin-7-glucoside, and chrysoeriol. Using quantitative chemotaxis capillary assays, we did not detect chemotaxis of motile S. meliloti cells to these, and two other flavonoids identified in seed exudates. In support of these findings, the flavonoid fraction of seed exudates was found to be an insignificant attractant relative to the more hydrophilic fraction. Additionally, we observed that cosolvents commonly used to dissolve flavonoids confound the results. We propose that the role flavonoids play in S. meliloti chemotaxis is insignificant relative to other components released by alfalfa seeds.

Regulating Dynamics of Polyether-Based Triblock Copolymer Hydrogels by End-Block Hydrophobicity

The relaxation dynamics of poly(ethyl glycidyl ether-co-isopropyl glycidyl ether-b-ethylene oxide-b-ethyl glycidyl ether-co-isopropyl glycidyl ether) triblock copolymer hydrogels were investigated as a function of the end-block hydrophobicity and temperature primarily using the oscillatory rheometer, which is crucial to understand the unique viscoelastic behaviors including injectability and self-healing property of the self-assembled hydrogels. Lower critical solution temperature behavior of the poly(alkyl glycidyl ether) end-blocks was harnessed by random copolymerization of poly(ethyl glycidyl ether) (EGE) and poly(isopropyl glycidyl ether) (iPGE), resulting in the remarkable temperature responsiveness of the hydrogel. As the fraction of hydrophilic monomer (i.e., EGE) increases, the sol-to-gel transition occurs at higher temperature and higher polymer concentration. The hydrogel relaxation measured by the oscillatory rheometer becomes faster with decreasing temperature and increasing fraction of hydrophilic monomers. In particular, we observed that a small increment of the hydrophilic monomer fraction significantly reduces the unfavorable interaction between the end-block and aqueous media, resulting in faster hydrogel relaxation dynamics. All polyether-based hydrogels showed biocompatibility and injectability, indicating promising soft materials for biological and biomedical applications. The results are discussed in terms of the current understanding of self-assembled triblock copolymer hydrogels, and particular attention is paid to the issue of chain dynamics.

Chemometric Analysis of Extracts and Fractions from Green, Oxidized, and Microbial Fermented Teas and Their Correlation to Potential Antioxidant and Anticancer Effects.

Previous reports on phytochemicals in green tea (GT) and processed teas mainly focused on more representative compounds such as catechins. Here, we focus on the insignificantly studied non-catechin components in tea extracts, and explore the multivariate correlation between diverse phenolic compounds in tea and the in vitro antioxidant and anticancer effects. Extracts from GT and four types of processed teas were further divided into hydrophilic and hydrophobic fractions, whose phenolic compositions and antioxidant capacities were quantified using HPLC-MS and three antioxidant assays, respectively. For three types of teas, the anticancer effects of their extracts and fractions were assessed using cancer cell lines. The hydrophobic fractions had lower antioxidant capacities than the corresponding hydrophilic fractions, but exhibited superior antiproliferative effects on cancer cells compared with the whole extract and the hydrophilic fraction. Partial least squares-discriminant analysis revealed a strong correlation between the anticancer effects and the theaflavins and flavonols. Therefore, in addition to catechins, the hydrophobic fraction of tea extracts may have beneficial health effects.

The profile of contamination with alkylphenol ethoxylates of some Israeli watercourse rivers and their sediment layers

Abstract The ‘hard’ non-biodegradable alkylphenol ethoxylates (APEOs) nonionic surfactants are environmentally persistent and widely used worldwide. The aim of this work is to determine the total concentration and the homological distribution in rivers and there sediments, in central Israel. The concentrations of APEOs in the water of these rivers and in their sediments were found to be 11.83–55.32 μg/L, and 99.68–1,176.61 μg/kg, respectively. The APEOs' concentration level decreases as the sample is taken from a deeper layer of the sediment. A possible explanation for this is that in APEOs molecules, the hydrophilic fraction (CH2-CH2-O) increases the APEOs' absorption into sediment layers close to water, being saturated with water. In addition, the organic biofilm in the sediment layers used as schmutzdecke can reduce the concentration levels of APEOs that penetrates the deep layers of the sediment. The dominant homologues of APEOs in the river watercourse were those with 9–15 units of ethylene oxide (EO). Homologues with 1–12 units of ethylene oxide were found to be the dominant ones in the sediment layers of Hadera and Alexander rivers.

Bioactive Compounds and Antioxidant Capacity of Moringa Leaves Grown in Spain Versus 28 Leaves Commonly Consumed in Pre-Packaged Salads

Total antioxidant capacity (TAC) evaluated by ferric ion reducing antioxidant power (FRAP) assay, ABTS, DPPH, and Oxygen radical absorbance capacity (ORAC) assay, and total polyphenol content (TPC) by Folin–Ciocalteu were determined in Moringa oleifera leaves (MO) grown in Spain, and compared with 28 different vegetable leaves pre-packaged for consumption as a salad. Total carotenoids, flavonoids, and chlorophylls were also determined in the samples with highest TAC. Two different extraction procedures were applied to obtain the methanolic fraction and the lipophilic and hydrophilic fractions. The highest TAC and TPC contents were found in MO. High values were also found in red chicory, “lollo rosso”, and oak lettuce. The lowest TAC and TPC values were obtained in iceberg lettuce. The correlations between the extraction procedures and methods assayed were high and statistically significant. In the light of these results, we suggest the addition of MO to the existing range of fresh-cut salad foods would increase their antioxidant content by up to six times.