Components of “soybean lecithin”

Summary The acetone-insoluble material from soybean “lecithin” has been fractionated by submitting alcohol-soluble and alcohol-insoluble portions to countercurrent distribution between hexane and methanol. The alcohol-soluble portion was found to contain lecithin, cephalin, and sugars or glycosides; the alcohol-insoluble portion was separated into two major inositol-containing phosphatides and sugars or glycosides. While the commonly accepted value of 30–35% for lecithin in the phosphatides was confirmed, it appears that the accepted value of 65% of cephalin needs revision. The approximate composition for one sample of soybean phosphatides is estimated to be 29% lecithin, 31% cephalin, and 40% inositol-phosphatides. Presented at the 39th Annual Meeting of the American Oil Chemists' Society, May 4–6, 1948, in New Orleans, Louisiana. This paper reports results obtained from a research project financed by the Research Marketing Act of 1946. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.     

Sources of color in soybean “lecithin”

The color of soybean lecithin is due to carotenoids, brown pigments, and occasionally porphyrins. In the water-washing of crude oil xanthophylls are preferentially removed with the gums, and carotene is practically absent in lecithin. Lutein is the principal carotenoid, comprising about three-quarters of the carotenoids in lecithin. Hydrogen peroxide bleaching destroys all the color to some extent, but by far the greater effect is on the carotenoids. The brown color is very likely an aldehyde amine reaction product. It is largely formed by heating of the oil during the solvent-stripping operation. It is not increased by drying the gums under vacuum for 3 hours at 80°C. but it is increased on heating at 100° C. under the same conditions. The formation of the brown color is not prevented by removal of free sugars or by hydrogenation of the lecithin.     

Synthesis and evaluation of 1-amino-6-halo-β-carbolines as antimalarial and antiprion agents

Malaria is one of the world's most devastating parasitic diseases, causing almost one million deaths each year. Growing resistance to classical antimalarial drugs, such as chloroquine, necessitates the discovery of new therapeutic agents for successful control of this global disease. Here, we report the synthesis of some 6-halo-β-carbolines as analogues of the potent antimalarial natural product, manzamine A, retaining its heteroaromatic core whilst providing compounds with much improved synthetic accessibility. Two compounds displayed superior activity to chloroquine itself against a resistant Plasmodium falciparum strain, identifying them as promising leads for future development. Furthermore, in line with previous reports of similarities in antimalarial and antiprion effects of aminoaryl-based antimalarial agents, the 1-amino-β-carboline libraries were also found to possess significant bioactivity against a prion-infected cell line.     

Dithizone and carbazone complex compounds as initiators and γ -radiation anti-degradation agents for poly(methyl methacrylate)

It has been proved that lead dithizone and carbazone complex compounds act as adequate initiators and indicators for radical polymerization of methylmethacrylate. The color change observed during the polymerization process was attributed to the change in structure of the complex compounds according to tautomerization mechanism. Improvements to both polydispersity and relative crystallinity were observed in presence of lead dithizone and carbazone complex compounds. Better protection against gamma radiation was noticed ascertained through molecular mass measurements. A convincing reaction mechanism was also given.     

Synthesis and characterization of new Mg–O–F system and its application as catalytic support

The Mg–O–F system (MgF₂–MgO) with different contents of MgF₂ (100–0%) and MgO is tested as support of iridium catalysts in the hydrogenation of toluene as a function of the MgF₂/MgO ratio. Mg–O–F samples have been prepared by the reaction of magnesium carbonate with hydrofluoric acid. The MgF₂–MgO supports, after calcination at 500 °C, are classified as mesoporous of surface area (34–135 m²·g^− 1) depending on the amount of MgO introduced. The Ir/Mg–O–F catalysts have been tested in the hydrogenation of toluene. The highest activity, expressed as TOF, min^− 1, was obtained for the catalyst supported on Mg–O–F containing 75 mol%MgF₂.     

Synthesis of α,α′-dipotassio-m-xylene and its use as a dianionic initiator

Summary ,-Dipotassio-m-xylene was prepared by di-metalation of m-xylene with a butyllithium/potassium t-butoxide mixed base system. Its functionality was determined by combining the dianion with chlorotrimethylsilane which resulted in the di-substituted carbosilane. GC and ¹H NMR analysis confirmed that the di-substituted carbosilane was synthesized in>90% yield. The effectiveness of this dianion as an initiator for living anionic polymerization was demonstrated by the polymerization of isoprene and the synthesis of the triblock copolymer of dimethylacrylamide-isoprene-dimethylacrylamide.     

Hydrolyzed soy protein isolates modified urea–formaldehyde resins as adhesives and its biodegradability

The hydrolytes soy protein isolates (HSPI)-modified urea–formaldehyde (UF) resins were synthesized via copolymerization process. The best bonding strength is 1.50 MPa and improves 51.5% compared with pure UF. In addition, the formaldehyde emission decreased. The effect of (HSPI) on the biodegradable (UF) resins was investigated. Biodegradation was evaluated by composting under controlled conditions in accordance with ISO 14855. The faster degradation rate was obtained when lower hydrolysis degree of HSPI was added into the system. Characterization of the resulting samples was performed by attenuated total reflection Fourier transform infrared spectroscopy, thermo-gravimetric analysis, XRD, scanning electron microscopy, and AFM. The results showed that no evidence of biodegradation was found for UF resins. The UF modified with lower hydrolysis degree of hydrolytes soy protein isolates (HSPI) resulted in a faster degradation rate. The HSPI in the network of modified UF degraded first, which resulted in the broken of the network of HSPI-modified UF resins. The thermal stability of degraded resins was found to be enhanced as the mineralization time increased. Not only the surface of the sample was degraded, but also the crystalline regions of the samples were also decomposed. The degradation on the modified UF surface occurs mainly via the formation of holes. The roughness of the degraded surfaces of modified UF resins increases with the hydrolysis degree of HSPI decreases. The presence of HSPI has driven the degradation of urea–formaldehyde. The modified resins used as adhesives in biodegradable seedling container can be seen as a controlled release source of nitrogen fertilizer.     

Sterol fractions in hazelnut and virgin olive oils and 4,4′-dimethylsterols as possible markers for detection of adulteration of virgin olive oil

Reports on the methylsterol fractions of hazelnut oils are scarce. The objectives of this study were to characterize methylsterols in hazelnut and virgin olive oils and to study the possibility of detection of adulteration of virgin olive oils. In hazelnut oils, 4-desmethylsterols were present in higher proportions (86 to 91%) than in virgin olive oils where this fraction was ca. 50% of the total sterol. In the 4-monomethylsterol fraction, citrostadienol was the major component in both kinds of oils followed by cycloeucalenol and obtusifoliol in virgin olive oils, and obtusifoliol in hazelnut oils. 24-Methylenecycloartanol was predominant in both kinds of oils in the 4,4′-dimethylsterols. For the first time, δ-amyrin was tentatively identified by comparing published mass spectral data in the analyzed samples of both kinds of oils. An unknown compound X (containing a lupane skeleton) and lupeol were detected only in the 4,4′-dimethylsterols fraction of hazelnut oils at a level of 2–8 and 6–10%, respectively. GC-MS analysis showed that adulteration of virgin olive oil by hazelnut oil could be detected at a level less than 4% by using these two compounds as possible potential markers.     

Covalently crosslinked hyaluronan–polygalacturonic acid polymer as the drug carrier and its application in surgery

The composite material based on the hyaluronan (HA) and polygalacturonic acid (PGA) was synthesized for tissue anti-adhesion. HA and PGA were cross-linked covalently by disulfide bonds through thiol oxidation reaction. HA and PGA were grafted with cysteine to yield thiolated HA (HA_cys, with thiol content of 337 ± 72 μmol/g) and PGA (PGA_cys, with thiol content of 752 ± 77 μmol/g), respectively. A HA_cys–PGA_cys film was fabricated under physiological conditions, with gel content of 84.8 ± 1.7 % and water content of 46.9 ± 2.2 %. The HA_cys–PGA_cys film was used as the anti-inflammatory drug (rosmarinic acid (RA)) carrier to prevent postsurgical adhesion. The in vitro dynamic release behavior of RA from the HA_cys–PGA_cys film was analyzed. The RA-entrapped film displayed release profile with an initial burst about 80 % of loaded RA in the early stage. The late phase release of RA from the HA_cys–PGA_cys film after 24 h followed the zero order (R ² = 0.978). Animal implant studies of the HA_cys–PGA_cys and HA_cys–PGA_cyswith rosmarinic acid (HA_cys–PGA_cys/RA) films reduced adhesion incidences by 83 and 92 %, respectively. To evaluate the efficiency of a combination of physical barriers and an RA anti-inflammatory drug, white blood cell counts from histological sections was done on day 3 after surgery. The results showed that the number of WBCs in the section with the HA_cys–PGA_cys/RA film decreased by 26.8 % compared with the section with HA_cys–PGA_cys film. The newly developed HA_cys–PGA_cys composite polymer showed great potential as the drug carrier and also for postoperative adhesion prevention.     

Asymmetric supercapacitor based on novel coal fly ash derived metal–organic frameworks as positive electrode and its derived carbon as negative electrode

Journal of Applied Electrochemistry - The paper presents a comparative study between aluminum fumarate metal–organic framework (Al-FumMOF) and a novel coal fly ash derived aluminum MOF...     

Crop yields and soil organic carbon fractions as influenced by straw incorporation in a rice–wheat cropping system in southeastern China

In agro-ecosystems, the relationship between soil fertility and crop yield is mediated by manure application. In this study, an 8-year field experiment was performed with four fertilizer treatments (NPK, NPKM₁, NPKM₂, and NPKM₃), where NPK refers to chemical fertilizer and M₁, M₂, and M₃ refer to manure application rates of 15, 30, and 45 Mg ha^?1 year^?1, respectively. The results showed that the NPKM (NPKM₁, NPKM₂, and NPKM₃) treatments produced greater and more stable yields (4.95–5.45 Mg ha^?1 and 0.59–0.75) than the NPK treatment (4.01 Mg ha^?1 and 0.50). Crop yields under the NPKM treatments showed two trends, with a rate of decrease of 0.48–0.83 Mg ha^?1 year^?1 during the first 4 years and a rate of increase of 0.10–0.25 Mg ha^?1 year^?1 during the last 4 years. The soil organic carbon (SOC) significantly increased under all treatments. The estimated annual SOC decomposition rate was 0.35 Mg ha^?1 year^?1 and the equilibrium SOC level was 6.22 Mg ha^?1. Soil total nitrogen (N), available N, total phosphorus (P) and available P under the NPKM treatments increased by 0.15–0.26, 15–33, 0.17–0.66 and 45–159 g kg^?1, respectively, compared with the NPK treatment. Manure application mainly influenced crop yield by affecting the soil TN, available N, and available P, which accounted for up to 64% of the crop yield variation. Taken together, applying manure can determine or at least improve the effects of soil fertility on crop yield in acidic soils in South China.     

Open-Cell Polyurethane Foam Sponge as a “Solvent Extractor” for Gallium and Iron

Abstract

Open-cell polyurethane foam has been shown to be effective in separating gallium and iron from aluminum in acid chloride solutions. Evidence is presented which indicates that the solid organic polymer acts as a “solvent extractor” for complex acid chlorides of gallium and iron.     

Large-scale synthesis of ordered mesoporous carbon fiber and its application as cathode material for lithium–sulfur batteries

A novel type of one-dimensional ordered mesoporous carbon fiber has been prepared via the electrospinning technique by using resol as the carbon source and triblock copolymer Pluronic F127 as the template. Sulfur is then encapsulated in this ordered mesoporous carbon fibers by a simple thermal treatment. The interwoven fibrous nanostructure has favorably mechanical stability and can provide an effective conductive network for sulfur and polysulfides during cycling. The ordered mesopores can also restrain the diffusion of long-chain polysulfides. The resulting ordered mesoporous carbon fiber sulfur (OMCF-S) composite with 63% S exhibits high reversible capacity, good capacity retention and enhanced rate capacity when used as cathode in rechargeable lithium–sulfur batteries. The resulting OMCF-S electrode maintains a stable discharge capacity of 690 mAh/g at 0.3 C, even after 300 cycles.     

Design of nitrogen-containing organic thermal stabilizer with resistance to “zinc burning” and its application

Using maleic anhydride and 6-amino-1,3-dimethyluracil as raw materials, by adding zinc oxide and introducing metal ions, the aminouracil zinc maleate (AM-Zn) was synthesized. The structure of the product was analyzed by Fourier transform infrared spectroscopy and ¹H NMR spectroscopy. The molecule contains ester group, carbon–carbon double bond, carboxylate and diazo group, which can be used as the main thermal stabilizer for poly(vinyl chloride) (PVC). The thermal stability and excellent resistance to zinc burning of AM-Zn were characterized by Congo red method, thermal aging method, thermal weight loss method, electrical conductivity, and other detection methods. In addition, the compound use of AM-Zn and CaSt₂ could further improve the thermal stability performance, which was excellent compared with the commercially available CaSt₂/ZnSt₂. The thermal stabilization effect was the best when CaSt₂/AM-Zn = 2:1, the initial whiteness could reach 50 min, and it was not completely blackened and aged within 80 min. The static stabilization time was 65 min, and the thermal stabilization time is increased by 40 min compared with CaSt₂/ZnSt₂. The thermal stabilization mechanism was analyzed, and the designed and synthesized AM-Zn, a multifunctional molecular structure, had a strong potential as a thermal stabilizer for PVC.     

Prevention of Osteoporosis by Oral Administration of Phytate-Removed and Deamidated Soybean β-Conglycinin

Phytate-removed and deamidated soybean β-conglycinin (PrDS) prepared by ion-exchange resins was supplemented to be 4% in the diet administered to ovariectomized rats to investigate its preventive effect on osteoporosis. The apparent calcium absorption rate decreased following ovariectomy and was not replenished by oral administration of phytate-removed soybean β-conglycinin (PrS) or casein. On the other hand, administration of PrDS restored the calcium absorption rate to the same level as the sham group. Markers of bone resorption, such as serum parathyroid hormone (PTH) and urinary deoxypyridinoline (DPD), increased, and the bone mineral density and breaking stress decreased following ovariectomy. However, PrDS supplementation suppressed the changes caused by the decrease in calcium absorption from the small intestine. Therefore, PrDS supplementation shows promise for the prevention of postmenopausal osteoporosis.     

Mycotoxin Detection Plays “Cops and Robbers”: Cyclodextrin Chemosensors as Specialized Police?

As in a cops and robbers play we discover new mycotoxins and metabolites everyday and we are forced to develop new molecules quickly as chemo- or biosensors or to modify existing molecules able to recognize these new hazardous compounds. This will result in an enormous cost saving to agro-food industry through the prevention and reduction of product recalls and reduced treatment costs. Here we present a brief review of the rapid methods used to detect mycotoxins, considering usefulness and limits. Then we propose a new fast, efficient and cheap methodology, based on a combination of computer chemistry aided design and fluorescence, that can help to drive synthesis in a more efficient way.     

Preparation of Xylan–Acrylic Acid Polymer with High Molecular Weight and its Application as a Dye Removal Flocculant

Xylan is found in natural products and can be used for preparing value-added products. The main purpose of this study was to produce a xylan-based polymer (xylan–acrylic acid [Xy–AA]) as a flocculant for removing ethyl violet dye from wastewater. In this study, the polymerization reaction of xylan and acrylic acid (AA) was optimized by response surface methodology (RSM). It was indicated that the maximum charge density of –5.87?mmol/g and molecular weight of 352,028?g/mol were obtained for Xy–AA polymer under the conditions of 20.53?g/L xylan concentration, 0.31 xylan/AA molar ratio, 2.5?h reaction time, and 72?°C reaction temperature. The polymer was characterized by charge density analyzer, Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (¹H-NMR), and thermogravimetric analysis (TGA). The application of the product as a flocculant for removing the ethyl violet from simulated dye solution was evaluated. The results showed that the optimal dye removal of 97.08% was achieved under the conditions of 50?mg/L dye concentration, 120?mg/L Xy–AA concentration, pH 10, and 30?°C. The flocculation mechanism was also discussed.     

Selective modification of the N-terminal structure of polytheonamide b significantly changes its cytotoxicity and activity as an ion channel

Chemical point mutation: Polytheonamide?B is a naturally occurring polypeptide containing 48 amino acids. It both displays potent cytotoxicity and acts as a monovalent cation channel in?vitro. Chemoselective methods to modify the 44th, N-, and C-terminal residues of the natural product have been developed, and evaluation of the resultant derivatives suggests that the intrinsic activities of the peptide can only be altered by switching its N-terminal substitution.     

On-site pXRF analysis of glaze composition and colouring agents of “Iznik” tiles at Edirne mosques (15th and 16th-centuries)

The production of the tiles in Ottoman Empire had begun as a continued workshop of Seldjuk ceramic art, and after this initial phase, its own technology was introduced into Ottoman art by local craftsmen. Iznik tiles are among the most appreciated pottery masterpieces, and wall decoration in tiles is a significant asset of Unesco World Heritage Edirne mosques. Rare glaze composition studies have been made, which justify the need for more comprehensive studies. We present here the first on-site elemental analyses performed with portable XRF instrument in four of the most representative mosques in Edirne (?ah Melek Pa?a (1429), Muradiye (1435–1436), Üç ?erefeli (1410–1447) and Selimiye (1569–1575)). A handheld 785?nm Raman spectrometer was used as a complementary technique to identify some pigments. About forty tiles have been analysed in this research. Additionally, two tiles from Ye?ilce Mosque (1442, Edirne) have been analysed at the Selimiye Foundation Museum. The weight percent of the elements measured with pXRF are normalized by Si amount in order to eliminate the variation due to the positioning shifts. Different glazing technologies are evidenced (Master of Tabriz Sn-free glazed tiles, Hünkar Mahfili Sn-poor glazed tiles, and Sn-(Bi) rich ones). At least three different cobalt ores have been used (with characteristic Cu, Ni, Mn and Bi content) in blue decors. Use of a chromium-based ore is demonstrated for some Selimiye Hünkar Mahfili tiles. The link between ?ah Melek Pa?a and polychrome (mihrab) Muradiye tiles and Seldjuk production is established. On the contrary, the technology of Üç ?erefeli and blue-and-white Muradiye tiles is unique and appears a precursor of 16th-century Iznik production. Bismuth, Sn/Pb, Co/Mn, and Co/Ni ratio appears very useful to compare the different glazes and to identify mining sources of cobalt.     

Ultraviolet-protective thin film based on PVA–melanin/rod-coated silver nanowires and its application as a transparent capacitor

Melanin is a biopigment in many organisms with interesting intrinsic properties suitable for emerging and sustainable technologies. In this work, we report the fabrication of transparent ultraviolet (UV)-protective thin films based on synthetic melanin in poly(vinyl alcohol) (PVA) matrixes. Melanin was synthesized through the auto-oxidation of l -3,4-dihydroxyphenylalanine (l -DOPA) under oxygen pressure, resulting in excellent solubility in water. A thin film with a composition of 3 wt % melanin (synthesized at 6 atm oxygen pressure) and silver nanowires (AgNWs) deposited on the surface has good transparency in visible light and 100% UV irradiation photoprotection. Encapsulated PVA–melanin/AgNW films dipped in water for 7 days retained 98% of their UV irradiation photoprotection. Moreover, using a transparent conductive oxide substrate, this UV-protective system can be simultaneously used as a transparent capacitor. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47805.