Allyl Methyl Research Articles

Validation of a High-Performance Liquid Chromatography Photo-Diode Array Method for the Temperature Effects on Alk(En)yl Sulfides in Garlic Extracts

A sensitive analytical method employing a high-performance liquid chromatography photo-diode array system for the determination of allicin and alk(en)yl sulfides, including the diallyl, allyl methyl, and dimethyl sulfide series, was developed and validated. The method was evaluated in terms of linearity, limit of detection, limit of quantification, precision, and accuracy, and exhibited excellent linearity for all the analytes (R > 0.999). The intra-day and inter-day precision of the method was expressed as the relative standard deviation for each analyte and ranged from 0.17 to 3.75% and 0.53 to 10.83%, respectively. The recovery tests ranged from 85.89 to 106.99% for allicin and alk(en)yl sulfides, respectively. Using the developed analytical method, the changes in the allicin and alk(en)yl sulfide contents of garlic extracted obtained with different solvents were evaluated over one month of storage at 4 and 25°C. The allicin in the garlic extracts was found to be stable at 4°C, but relatively unstable at 25°C. The alk(en)yl sulfide content of the extracts increased continuously at 25°C, but much more slowly at 4°C. The results of our study suggest that our method may be useful in controlling the quality and clinical applications of processed garlic and its products.

Deposition Kinetics and Thermal Properties of Atmospheric Plasma Deposited Methacrylate-Like Films

Allyl methacrylate (AMA), methyl methacrylate (MMA), and propyl isobutyrate (PiB) are plasma deposited at ambient temperature in an atmospheric DBD reactor to assess the effect of precursor carbon double bond unsaturations. The specific plasma deposition rate (k0) as a function of the Yasuda factor (Yf) is quantified empirically by: k0 = b (1 − exp(–a Yf/b)). Fourier transform infrared analysis indicates a loss of carbonyl functionalities with increasing plasma power, and Raman microscopy shows CC double bonds in all plasma films. The methacrylate-like plasma films are found to be heterogeneous with a volatile and a cross-linked fraction observed by thermogravimetric analysis. Differential scanning calorimetry reveals a low glass transition temperature and a characteristic residual reactivity of the coatings.

Spices and herbs in broilers nutrition: Effects of garlic (Allium sativum L.) on broiler chicken production

The aim of this review paper is to show the most important bioactive compounds of garlic (Allium sativum L.), modes of action of garlic powder and its effects on broiler chicken productive performance. Allicin is thought to be the principal bioactive compound present in aqueous garlic extract or raw garlic homogenate. When garlic is chopped or crushed, the allinase enzyme present in garlic is activated and acts on alliin to produce allicin. Other important sulphur containing compounds present in garlic are allyl methyl thiosulphonate, 1-propenyl allyl thiosulphonate and γ-L-glutamyl-S-alkyl-L-cysteine. These active compounds are thought to influence feed consumption, feed utilisation, body weight, blood lipid profiles and cholesterol levels in chickens. Biological responses to these bioactive compounds have been attributed to a reduction in risk factors for cardiovascular diseases and cancer, stimulation of immune function, enhanced detoxification of foreign compound, hepatoprotection, antimicrobial, antifungal, anti-inflammatory and antioxidant effects.

Molecular dynamics study of the effects of calcium ions on the conformational properties of comb-like poly(acrylic acid-co-methyl allyl polyoxyethylene ether)

All-atom molecular dynamics simulations were employed to study the microscopic conformational properties of three kinds of comb-like poly(acrylic acid-co-methyl allyl polyoxyethylene ether) (P(AA-co-MAPEG)) in solution. Two different systems, which contained single chain and two chains respectively, were studied, and the binding types of calcium ions (Ca2+) to carboxylate groups (–COO−) were analyzed. For the systems containing a single chain, as the concentration of Ca2+ increased, the value of the radius of gyration, Rg, for P(AA-co-MAPEG) (4:1) (4:1 represented the monomer ratios of acrylic acid to polyoxyethylene methyl allyl ether, the same description below) chain sharply decreased in Ca2+ solution because Ca2+ weakened the repulsive electrostatic interactions between the charged –COO− while hardly interacted with –COO− directly (e.g. coordination). And the values of Rg for the P(AA-co-MAPEG) (6:1) chain and P(AA-co-MAPEG) (9:1) chain changed slightly because Ca2+ easily interacted with the –COO−, and the polymer chains exhibited a more rigid conformation. For the systems containing two chains, due to two competing factors, the solvation of –COO− and steric hindrance induced by side chains, it was favorable for P(AA-co-MAPEG) (6:1) chains to approach each other to form intermolecular Ca2+ bridges. For comb-like polyelectrolyte, intermolecular binding was difficult to form than intramolecular binding. And among all the possible intramolecular binding modes, the type of Ca2+ binding to two oxygen atoms of adjacent –COO− was the most favorable.

ChemInform Abstract: Synthesis of Allylated Quinolines/Isoquinolines via Palladium‐Catalyzed Cyclization—Allylation of Azides and Allyl Methyl Carbonate.

AbstractA novel one‐step synthesis of allylated quinolines and isoquinolines is achieved by Pd‐catalyzed reaction of aryl or benzyl azides bearing an ortho‐alkynyl substituent with allyl methyl carbonate as optimized reagent.

ChemInform Abstract: Highly Regio‐ and Enantioselective Synthesis of N‐Substituted 2‐Pyridones: Iridium‐Catalyzed Intermolecular Asymmetric Allylic Amination.

AbstractThe Ir‐catalyzed asymmetric allylic amination of 2‐hydroxypyridines with allyl methyl carbonates (II) is reported for the first time.

Allyl methyl disulfide inhibits IL-8 and IP-10 secretion in intestinal epithelial cells via the NF-кB signaling pathway.

Garlic and its active constituents have shown versatile medicinal activities in the prevention and treatment of various disorders. Allyl methyl disulfide (AMDS) was identified as one of the major bioactive components in an effective inhalation fork remedy using fresh garlic paste in our previous study. In this work, we investigated the immunological properties of AMDS to elucidate the underlying mechanisms of the fork inhalation treatment using fresh garlic. The inhibition effect of AMDS on TNF-α-induced IL-8 and IP-10 production in intestinal epithelial cell lines HT-29 and Caco-2 was first evaluated. Pretreatment of the cells with AMDS attenuated IL-8 and IP-10 secretion induced by TNF-α in a dose-dependent manner in the non-cytotoxic concentration range of 20 to 150 μM. Mechanistic studies revealed that AMDS suppressed the accumulation of IL-8 mRNA and inhibited IкBα degradation and NF-кB p65 translocation into the nucleus at both the transcriptional and translational levels, suggesting that the attenuation effort of AMDS on cytokine IL-8 secretion might at least be partially related to the NF-κB signaling pathway. These results suggest that AMDS may be a promising phytochemical agent in the treatment of immunological disorders, such as ulcerative colitis, Crohn's disease, intestinal inflammatory diseases and others. In addition, the mechanistic study data indicated that immune modulation could be one of the therapeutic mechanisms of the effective fork treatment containing AMDS as one of the major components.

Soft ruthenium and hard Brønsted acid combined catalyst for efficient cleavage of allyloxy bonds. Application to protecting group chemistry

We show that a monocationic CpRu(II) complex of quinaldic acid (QAH) and a monocationic CpRu(IV)(π-allyl)QA complex catalyze efficient cleavage of the allyloxy bond in allyl ethers, allyl esters, allyl carbonates, and allyl carbamates in methanol without the need for additional nucleophiles. The only co-product is volatile allyl methyl ether, enhancing operational simplicity during isolation of the deprotected alcohols, acids, and amines. This clean and high-performance catalytic system should contribute to protecting group chemistry during the multistep synthesis of pharmaceutically important natural products. Full details of this system, including the mechanism, are reported.

Sunlight‐Induced Cross‐Linked Luminescent Films Based on Polysiloxanes and d‐Limonene via Thiol–ene “Click” Chemistry

The increasing pursuit of biocontained elastic materials led the investigation of the potential use of the monoterpene limonene in film synthesis via thiol–ene reaction. Poly[(mercaptopropyl)methylsiloxane] (PMMS) is first synthesized. By controlling the molar ratio of PMMS and functional monomers, such as polyethylene glycol allyl methyl ether or rhodamine‐B, PMMS is partially functionalized while leaving spare mercapto groups that could be further used as cross‐linking sites. On the basis of the functionalized PMMS, novel transparent silicone luminescent films with hydrophilic tunable properties are prepared by natural‐sunlight‐triggered thiol–ene “click” chemistry by using d‐limonene as a cross‐linker. Their structures and properties are thoroughly characterized. Transparent luminescent films are coated on commercially available UV‐light emitting diode (LED) cell from solution medium followed by an in situ cross‐linking step; a colorful LED cell is obtained through this facile and efficient method. The UV‐LED coated by films show very intense photoluminescence under normal visible light or the light is on, and has very high coloric purity.

Analysis of Breath Specimens for Biomarkers of Plasmodium falciparum Infection.

Currently, the majority of diagnoses of malaria rely on a combination of the patient’s clinical presentation and the visualization of parasites on a stained blood film. Breath offers an attractive alternative to blood as the basis for simple, noninvasive diagnosis of infectious diseases. In this study, breath samples were collected from individuals during controlled malaria to determine whether specific malaria-associated volatiles could be detected in breath. We identified 9 compounds whose concentrations varied significantly over the course of malaria: carbon dioxide, isoprene, acetone, benzene, cyclohexanone, and 4 thioethers. The latter group, consisting of allyl methyl sulfide, 1-methylthio-propane, (Z)-1-methylthio-1-propene, and (E)-1-methylthio-1-propene, had not previously been associated with any disease or condition. Before the availability of antimalarial drug treatment, there was evidence of concurrent 48-hour cyclical changes in the levels of both thioethers and parasitemia. When thioether concentrations were subjected to a phase shift of 24 hours, a direct correlation between the parasitemia and volatile levels was revealed. Volatile levels declined monotonically approximately 6.5 hours after initial drug treatment, correlating with clearance of parasitemia. No thioethers were detected in in vitro cultures of Plasmodium falciparum. The metabolic origin of the thioethers is not known, but results suggest that interplay between host and parasite metabolic pathways is involved in the production of these thioethers.

Laboratory Evaluation of Larvicidal Activity of the Essential oil of Allium tuberosum Roots and its Selected Major Constituent Compounds Against Aedes albopictus (Diptera: Culicidae).

The aim of this research was to evaluate larvicidal activity of the essential oil of Allium tuberosum Rottler ex Sprengle roots and its constituents against larval mosquitoes (Aedes albopictus Skuse). Essential oil of A. tuberosum was obtained by hydrodistillation and analyzed by gas chromatography and gas chromatography-mass spectrometry. The major constituents of the oil were found to be sulfur-containing compounds, including allyl methyl trisulfide (35.19%), diallyl disulfide (28.31%), diallyl trisulfide (20.91%), and dimethyl trisulfide (12.33%). The essential oil of A. tuberosum exhibited larvicidal activity against the fourth-instar larvae of Ae. albopictus, with an LC50 value of 18 μg/ml. The constituents compounds-diallyl trisulfide (LC50 = 4 μg/ml) and diallyl disulfide (LC50 = 6 μg/ml)-possessed stronger larvicidal activity than allyl methyl trisulfide (LC50 = 27 μg/ml) and dimethyl trisulfide (LC50 = 35 μg/ml) against the fourth-instar larvae of Ae. albopictus. The results indicated that the essential oil of A. tuberosum and its major constituents have good potential as a source for natural larvicides.

Facile synthesis of functionalized 1H-pyrrolo[2,3-b]quinolines via Ugi four-component reaction followed by Cu-catalyzed aryl-amide, C–N bond coupling

A simple one-pot two-step reaction comprising an Ugi four-component reaction (Ugi-4CR) and copper-catalyzed intramolecular amide-aryl cyclization of heteroaryl chloride with amide has been developed for the synthesis of functionalized 1H-pyrrolo[2,3-b]quinolines in moderate to good yields. The synthesized pyrrolo-fused quinoline was further examined for Pd-catalyzed intramolecular cyclization to afford [1,4]oxazine-fused pyrrolo quinoline 11 and to nucleophilic substitution reactions with allyl bromide and methyl iodide to afford the corresponding allyl and methyl ethers, 12 and 13, respectively.

Identification and Characterization of Volatile Organic Compounds of Fresh Plant Using Headspace Combined with Surface-Enhanced Raman Scattering

The spectra of volatiles of fresh garlic, Chinese chive and scallion plants were successfully recorded by headspace combined with surface-enhanced Raman scattering using the portable Raman spectrometer. For garlic: high intensity bands are present in 1622, 1397, 1287, 1182, 711, 569, 461 cm-1 and low intensity bands are present in 1017, 979, 918, 307 cm-1. For Chinese chives: the high intensity band is present in 672 cm-1 and low intensity bands are present in 1618, 1396, 1289, 1185, 575, 412, 274 cm-1 . For scallion high intensity bands are present in 699, 1023 cm-1 and low intensity bands are present in 369, 887, 1084, 1314 cm-1 . The main volatiles of fresh garlic, Chinese chive and scallion are diallyl disulfide, allyl methyl sulfide and 1-propanethiol respectively. As the bulk concentration changes, different conformers are absorbed on silver.

Determination of Volatile Compounds of Sucuk with Different Orange Fiber and Fat Levels

In this study, the effects of fat (10, 15 and 20%) and orange fiber (0, 2 and 4%) levels on volatile compounds of sucuk (Turkish dryfermented sausage) were investigated. The volatile compound profile of sucuk samples was analyzed by gas chromatography/mass spectrometry (GC-MS) by using a solid phase microextraction (SPME). 75 volatile compounds were identified in the sucuk samples. The volatile compounds identified were 11 aldehydes, 7 aliphatic hydrocarbons, 2 acids, 10 esters, 1 furan, 5 alcohols, 8 aromatic hydrocarbons, 6 ketones, 6 sulphur compounds, and 19 terpenes. It was determined that the use of orange fiber had significant (P<0.05) effects on a few volatile compounds (allyl methyl sulfide, copaene and caryophyllene). Alpha-thujene was significantly affected by fat level (P<0.05). Fat level also showed very significant effect on p-xylene and allyl methyl sulfide (P<0.01). As result, orange fiber and fat level had no significant effects on volatile profile of sucuk samples.

RADIOPROTECTIVE EFFECT OF RAMSON (ÁLLIUM URSÍNUM L.) AND BOG BILBERRY (VACCINIUM ULIGINOSUM L.)

Radioprotective properties of the products produced from ramson ( Allium Ursinum L.) and bog bilberry ( Vaccinium uliginosum L.) were studied. Mice fed with the dried ramson and the bog bilberry extract were irradiated by X-rays (8 Gray). Strong radioprotective effect of these plant products was registered . The ramson demonstrated more radioprotective effect in comparison with bog bilberry extract. The radioprotective effect of Allium is probably determined by cysteine sulfoxides and their degradation products, such as diallyl disulfide and allyl methyl disulfide. T he radioprotectors studied increase minimum parameters of erythropoiesis (red blood cell number and hematocrit) by a factor 1,5. R apid recovery of the parameter of the platelets number of peripheral blood in all groups in comparison with control was registered. The survival of mice fed with the dried ramson and the bog bilberry extract increased up to 60 and 53 %, correspondingly, in comparison with 6,7% in the control group . These substances do not have side effects and contraindications and may be considered as a promising radioprotectors.

Laboratory Evaluation of Acute Toxicity of the Essential Oil of Allium tuberosum Leaves and Its Selected Major Constituents Against Apolygus lucorum (Hemiptera: Miridae).

The aim of this research was to evaluate acute toxicity of the essential oil of leaves of Chinese chives, Allium tuberosum Rottler ex Spreng (Asparagales: Alliaceae) and its major constituents against Apolygus lucorum Meyer-Dür (Hemiptera: Miridae). The essential oil of A. tuberosum leaves was obtained by hydrodistillation and analyzed by gas chromatography and gas chromatography-mass spectrometry. The major constituents of the oil were sulfur-containing compounds, including allyl methyl trisulfide (36.24%), diallyl disulfide (27.26%), diallyl trisulfide (18.68%), and dimethyl trisulfide (9.23%). The essential oil of A. tuberosum leaves exhibited acute toxicity against Ap. lucorum with an LD50 value of 20.03 μg per adult. Among the main compounds, diallyl trisulfide (LD50 = 10.13 μg per adult) showed stronger acute toxicity than allyl methyl trisulfide (LD50 = 21.10 μg per adult) and dimethyl trisulfide (LD50 = 21.65 μg per adult). The LD50 value of diallyl disulfide against Ap. lucorum was 28.10 μg per adult. The results indicated that the essential oil of A. tuberosum and its major constituents may have a potential to be developed as botanical insecticides against Ap. lucorum.

Synthesis of allylated quinolines/isoquinolines via palladium-catalyzed cyclization-allylation of azides and allyl methyl carbonate.

A novel and efficient strategy for one-step synthesis of allylated quinolines and isoquinolines via palladium-catalyzed cyclization-allylation of azides and allyl methyl carbonate is developed for the first time. The results indicated that the regioselective synthesis of allyl- and diallyl-substituted quinolines/isoquinolines depends on different substituted groups at R(1) and R(4) positions, such as H or other groups. The reactions proceed smoothly in the presence of Pd(PPh3)4 and K3PO4 or NaOAc in DMF at 100 °C to give the corresponding allyl- and diallyl-substituted quinolines and isoquinolines in good to high yields.

A shape memory copolymer based on 2-(dimethylamino)ethyl methacrylate and methyl allyl polyethenoxy ether for potential biological applications

This study reports a novel shape memory copolymer synthesized with 2-(dimethylamino)-ethyl-methacrylate (DMAEMA) and methyl-allyl-polyethenoxy-ether (TPEG) for potential biological applications.

Composition of the Essential Oil of Allium neapolitanum Cirillo Growing Wild in Sicily and its Activity on Microorganisms Affecting Historical Art Crafts.

Essential oil of the aerial parts of Allium neapolitanum Cirillo collected in Sicily were analyzed by gas-chromatography-flame-ionization detection and gas-chromatography-mass spectrometry. Nineteen compounds were identified in the oil and the main components were found to be (E)-chrysanthenyl acetate (28.1%), (Z)-chrysanthenyl acetate (23.8%), (E)-β-farnesene (9.6%), dimethyl trisulfide (9.6%), camphor (7.4%), methyl allyl disulfide (6.8%) and 1-methyl-3-allyl trisulfide (5.8%). The essential oil showed good antimicrobial activity against 11 strains of test microorganisms, including several species infesting historical material.

In situ solvothermal growth of metal-organic framework-5 supported on porous copper foam for noninvasive sampling of plant volatile sulfides.

The present study reported on an in situ solvothermal growth method for immobilization of metal-organic framework MOF-5 on porous copper foam support for enrichment of plant volatile sulfides. The porous copper support impregnated with mother liquor of MOF-5 anchors the nucleation and growth of MOF crystallites at its surface, and its architecture of the three-dimensional channel enables accommodation of the MOF-5 crystallite seed. A continuous and well-intergrown MOF-5 layer, evidenced from scanning electron microscope imaging and X-ray diffraction, was successfully immobilized on the porous metal bar with good adhesion and high stability. Results show that the resultant MOF-5 coating was thermally stable up to 420 °C and robust enough for replicate extraction for at least 200 times. The MOF-5 bar was then applied to the headspace sorptive extraction of the volatile organic sulfur compounds in Chinese chive and garlic sprout in combination with thermal desorption-gas chromatography/mass spectrometry. It showed high extraction sensitivity and good selectivity to these plant volatile sulfides owing to the extraordinary porosity of the metal-organic framework as well as the interaction between the S-donor sites and the surface cations at the crystal edges. Several primary sulfur volatiles containing allyl methyl sulfide, dimethyl disulfide, diallyl sulfide, methyl allyl disulfide, and diallyl disulfide were quantified. Their limits of detection were found to be in the range of 0.2-1.7 μg/L. The organic sulfides were detected in the range of 6.0-23.8 μg/g with recoveries of 76.6-100.2% in Chinese chive and 11.4-54.6 μg/g with recoveries of 77.1-99.8% in garlic sprout. The results indicate the immobilization of MOF-5 on copper foam provides an efficient enrichment formats for noninvasive sampling of plant volatiles.