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1.
Saudi J Biol Sci ; 29(3): 1869-1880, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35280580

RESUMO

Micronutrient deficiency in the soil is one of the major causes of mango fruit and yield's poor quality. Besides, the consumption of such a diet also causes a deficiency of micronutrients in humans. Boron deficiency adversely affects the flowering and pollen tube formation, thus decreasing mango yield and quality attributes. Soil and foliar application of B are considered a productive method to alleviate boron deficiency. A field experiment was conducted to explore the Boron most suitable method and application rate in mango under the current climatic scenario. There were nine treatments applied in three replications. The results showed that application of T8 = RD + Borax (75 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) and T9 = RD + Borax (150 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) significantly enhanced the nitrogen, potassium, proteins, ash, fats, fiber, and total soluble solids in mango as compared to the control. A significant decrease in sodium, total phenolics contents, antioxidant activity, and acidity as citric acid also validated the effective functioning of T8 = RD + Borax (75 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) and T9 = RD + Borax (150 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) as compared to control. In conclusion, T8 = RD + Borax (75 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) and T9 = RD + Borax (150 g plant -1 as a basal application) + H3 BO3 (0.8% as a foliar spray) is a potent strategy to improve the quality attributes of mango under the changing climatic situation.

2.
Saudi J Biol Sci ; 29(3): 1386-1393, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35280589

RESUMO

Elevated concentrations of salts in soil and water represent abiotic stresses. It considerably restricts plant productivity. However, the use of alpha-tocopherol (α-toc) as foliar can overcome this problem. It can improve crop productivity grown under salinity stress. Limited literature is documented regarding its optimum foliar application on sunflower. That's why the need for the time is to optimize α-toc foliar application rates for sunflower cultivated in salt-affected soil. A pot experiment was performed to select a better α-toc foliar application for mitigation of salt stress in different sunflower cultivars FH (572 and 621). There were 2 levels of salts, i.e., control (no salt stress) and sodium chloride (120 mM) and four α-toc foliar application (0, 100, 200, and 300 mg L-1). Results showed that foliar application of 100 mg/L- α-toc triggered the remarkable increase in fresh shoot weight, fresh root weight, shoot, and root lengths under salinity stress in FH-572 and FH-621 over 0 mg/L- α-toc. Foliar application of 200 mg/L- α-toc was most effective for improvement in chlorophyll a, chlorophyll b, total chlorophyll and carotenoids compared to 0 mg/L- α-toc. Furthermore, an increase in A was noted in FH-572 (17%) and FH-621 (22%) with α-toc (300 mg L-1) application under saline condition. In conclusion, the 100 and 200 mg/L- α-toc are the best application rates for the improvement in sunflower FH-572 and FH-621 growth, chlorophyll contents and gas exchange attributes. Further investigations are needed to select a better foliar application rate between 100 and 200 mg/L- α-toc at the field level under the different agro-climatic zone and soil types.

3.
Saudi J Biol Sci ; 29(2): 970-974, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35197765

RESUMO

In this study, three concentrations (250, 500, and 1000 ppm) of abamectin 2% suspension concentration (SC) were used as cucumber seeds treatment. The seeds were treated with abamectin to reduce nematodes reproduction and their ability to penetrate the roots, then seed germination and plant growth were observed. All the concentrations didn't negatively affect seeds germination wherever the germination percent reached 80% at the concentration (1000 ppm) after 20 days of sowing. The effect of abamectin on root-knot nematode was studied by recording numbers of nematodes in 100 g/soil, numbers of the galls, egg mass on the root, and the nematode reproduction factor. All concentrations significantly affected the nematode reproduction parameters compared to control. Abamectin at (500 ppm) was the most effective concentration on reducing nematodes parameters, i.e., 26.57, 38.83, 47.40 %, and 3.15 for the above-mentioned parameters, respectively at the end of experimint. No significant difference between 500 ppm and 1000 ppm. We recommended using the abamectin in (500 ppm) concentration as a seed application to control Meloidogyne incognita in cucumber plants under greenhouse conditions to reduce its environmental toxic effect.

4.
Poult Sci ; 101(4): 101702, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35172233

RESUMO

This study was aimed to assess the impacts of aloe vera (AV) and clove (Cv) powder supplementation on growth performance, carcass quality, blood biochemistry, and hematology of Japanese quails and studying the possibility of using them as alternatives to antibiotics growth promotors as a natural safe products. Four hundred, 7-d old mixed sex chicks were divided into 4 groups of 5 replicates 20 birds per replicate including (10 males and 10 females). Birds in the control group (T1) were fed a diet containing Enramycin (0.02%) as an antibiotic growth promoter (AGP), while T2, T3 and T4, birds were supplemented with AV leaf powder, Cv powder and mixture of both at 0.5, 0.5 and 0.25 + 0.25% of feed, respectively. Results showed that total feed intake in all supplemented groups were significantly (P < 0.05) higher than T1. Weight gain and feed conversion ratio were significantly higher (P < 0.05) in T4 while T2 and T3 were better (P < 0.05) than T1. Breast yield and carcass weight were the highest (P < 0.05) in T4 while T2 and T3 were significantly better than T1. High density lipoprotein was highest (P < 0.05) in T4 whereas T2 and T3 showed higher value than T1. Blood cholesterol and serum enzymes (ALT, AST and ALP) values were significantly (P < 0.05) higher in Tl and lower in T4. The highest hemoglobin level was observed in T4. White blood cells were significantly (P < 0.05) higher in T3 and T4. No significant difference was observed in, red blood cells, serum total protein, calcium and phosphorous level, packed cell volume, neutrophils, lymphocyte, monocyte, and eosinophil. It is concluded from this experiment that AV and Cv supplementation improved breast yield and carcass weight without any harmful effect on the liver and blood biochemistry. This showed that the supplementation of AV and Cv powder can improve growth performance and it can work as an alternative of AGP.


Assuntos
Aloe , Syzygium , Ração Animal/análise , Animais , Galinhas , Coturnix , Dieta/veterinária , Suplementos Nutricionais , Feminino , Masculino , Pós
5.
PLoS One ; 17(2): e0262338, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35130268

RESUMO

The present study was carried out to explore and document traditional ethnobotanical knowledge of indigenous rural communities of Shiwalik mountainous range regarding tree flora of the area, District Bhimber of Azad Jammu and Kashmir, Pakistan. The local people of the area primarily depend on wild flora for life sustenance and cure of different infirmities. In this research, data was collected through visual appraisal and participatory rural approach using questionnaire method by applying semi-structured and structured-interview protocols (S4 Table). To validate and explore novelty of research work, various quantitative ethnobotanical indices like informant consensus factor, use value index, fidelity level, relative frequency of citation, relative importance of plants, rank order of priority, Jaccard index and priority ranking were used. The highest ICF was found for jaundice with 0.91 value followed by ICF values of 0.89, 0.86 and 0.85 for wounds, skin diseases and stomach pains, respectively. Fidelity level predicted that Azadirachta indica (Indian lilac tree) ranked first (100%) for its prevalent use in ethnomedicines. Highest use value index (0.61) was found for Azadirachta indica while the highest relative frequency of citation (55) was measured for Melia azedarach. The relative order of priority index was the highest for Azadirachta indica and Acacia arabica L. (ROP = 100) depicting their prevalent use in ethnomedicines. For EB study, the highest relative importance (50.8) was found for Azadirachta indica with good number of agro-uses and its seeds and bark are sold or marketed in local markets to prepare herbal therapeutics by indigenous practioners. The Jaccard index depicted that many traditional ethnomedicinal uses of prescribed trees were novel in recipe form or first time reported such as Senegalia modesta (Phulai) resin was used to prepare 'Panjoori' a local tonic prepared from cow or buffalo butter mixing with seeds of Papaver somnifera (Kashkhash) and Prunus amygdalus (Badaam). The wood of many trees like Pinus roxburghii (pine), Dalbergia sissoo (rosewood), Senegalia modesta (Phulai), Acacia. Arabica (kikar), Bombax cieba (cotton tree) is commercially sold as timber in markets (S3 Table). The research proved that population explosion and climate changes have triggered severe biotic and abiotic pressure on tree flora of the study area of Bhimber, AJK. The research describes that plants like Terminalia belerica (belerica), Terminalia arjuna (arjun tree), Cassia fistula (Indian laburnum), Butea monosperma (bastard teak), Phyllanthus emblica (Indian gooseberry), Morus laevigata (Shah toot), Bauhinia variegata (orchid tree) and Flacourtia indica (Indian plum/ kakoo) are threatened species and their population is highly reduced and if reclamation measures for their conservation are not taken, it may lead towards their complete loss from the area. This research recommends sustainable ethnobotanical use of tree flora, their growth and conservation for green and ecofriendly environment for safe and secure future of human generation.


Assuntos
Etnobotânica , Paquistão
6.
Environ Sci Pollut Res Int ; 29(23): 34887-34897, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35040058

RESUMO

Agricultural and agro-industrial wastes (e.g., potato peel waste) are causing severe environmental problems. The processes of pretreatment, saccharification, and fermentation are the major obstacles in bioethanol production from wastes and must be overcome by efficient novel techniques. The effect of exposing the fungi (yeast) Saccharomyces cerevisiae to laser source with the addition of graphitic carbon nitride nanosheets (g-C3N4) with different concentrations on bioethanol production was investigated through the implementation of a batch anaerobic system and using potato peel waste (PPW). Dichromate test was implemented as quantitative analysis for quantification of the bioethanol yield. The benefits of this test were the appearance of green color indicating the identification of ethanol (C2H5OH) by bare eye and the ease to calculate the bioethanol yield through UV-visible spectrophotometry. The control sample (0.0 ppm of g-C3N4) showed only a 4% yield of bioethanol; however, by adding 150 ppm to PPW medium, 22.61% of ethanol was produced. Besides, laser irradiations (blue and red) as influencing parameters were studied with and without the addition of g-C3N4 nanomaterials aiming to increase the bioethanol. It was determined that the laser irradiation can trigger the bioethanol production (in case of red: 13.13% and in case of blue: 16.14% yields, respectively) compared to the control sample (in absence of g-C3N4). However, by adding different concentrations of g-C3N4 nanomaterials from 5 to 150 ppm, the bioethanol yield was increased as follows: in case of red: 56.11% and, in case of blue: 56.77%, respectively. It was found that using fungi and exposing it to the blue laser diode source having a wavelength of 450 nm and a power of 250 mW for a duration of 30 min with the addition of 150 mg L-1 of g-C3N4 nanomaterials delivered the highest bioethanol yield from PPW.


Assuntos
Nanoestruturas , Solanum tuberosum , Biocombustíveis , Etanol , Fermentação , Grafite , Compostos de Nitrogênio , Saccharomyces cerevisiae , Solanum tuberosum/microbiologia
7.
Photodiagnosis Photodyn Ther ; 37: 102681, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34915183

RESUMO

The increase of microbial resistance poses threats to human health. Therefore, efficient treatment of microbial resistance is a global challenge.. During this study, the Ag/NiO nanocomposite was fabricated via simple and ecofriendly method, using Uncaria rhynchophylla extract as a reducing and capping agent to avoid the aggregation of as synthesized nanomaterials. Here, a range of characterization techniques were employed to characterize the sample which includes UV-vis spectroscopy, X-ray diffraction, FTIR spectroscopy, electron diffraction spectroscopy (EDX), scanning electron microscopy (SEM). Furthermore, the resultant nanocomposite demonstrated an efficient ability for the inhibition of both gram-positive and gram negative pathogenic multidrug resistant bacteria. Additionally, the Ag/NiO nanocomposite showed a durable antioxidant effect against DPPH that could still reach 63% at very low concentration, i.e. 0.5 mg/mL. Interestingly, the synthesized nanocomposite is efficient for the production of reactive oxygen species (ROS) and shows no hemolytic activity. Likewise, the Ag/NiO nanocomposite displayed excellent photocatalytic activity to degrade 85% methylene blue (MB) by 4 mg/25 mL and could be used for waste water treatment. It is believed that synthesized nanostructure with desirable morphology and preparation simplicity can be promising material for antimicrobial, antioxidant and catalytic applications.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Fotoquimioterapia , Antibacterianos/química , Antibacterianos/farmacologia , Catálise , Humanos , Nanocompostos/química , Fotoquimioterapia/métodos , Uncaria
8.
Int J Radiat Biol ; 98(2): 205-211, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34919001

RESUMO

PURPOSE: This study aimed to assess the radiological risk of natural radionuclides (226Ra, 232Th, and 40K) to marine ecosystem biota. MATERIALS AND METHODS: The study site in this was the Mediterranean Sea, Cyprus. With the use of the RESRAD-BIOTA (RESidual RADioactivity BIOTA) code, the tissue concentration, external and internal dose rate of aquatic animals and riparian animals were estimated. RESULTS: The total tissue concentrations of the aquatic animals and riparian animals were simulated at 1.14 × 106 Bq/kg (water media) to 0 Bq/kg (sediment media), and 1.33 × 106 Bq/kg (water media) to 9.79 × 101 Bq/kg (sediment media), respectively. The total dose rate for aquatic animals and riparian animals was ranged from 1.94 × 10-2 to 0 Gray per day (Gy/d) and 1.46 × 10-2 to 7.40 × 10-7 Gy/d, respectively. CONCLUSIONS: Based on the risk assessment of this study, there is no significant impact due to organisms' exposure to natural radioactivity. Although, further consideration of the exposure levels is required due to the potential effects of protracted low-level ionizing radiation.


Assuntos
Monitoramento de Radiação , Animais , Ecossistema , Mar Mediterrâneo , Radioisótopos/análise , Medição de Risco , Água
9.
Molecules ; 26(24)2021 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-34946758

RESUMO

Biofortification of pulse crops with Zn and Fe is a viable approach to combat their widespread deficiencies in humans. Lentil (Lens culinaris Medik.) is a widely consumed edible crop possessing a high level of Zn and Fe micronutrients. Thus, the present study was conducted to examine the influence of foliar application of Zn and Fe on productivity, concentration, uptake and the economics of lentil cultivation (LL 931). For this, different treatment combinations of ZnSO4·7H2O (0.5%) and FeSO4·7H2O (0.5%), along with the recommended dose of fertilizer (RDF), were applied to the lentil. The results of study reported that the combined foliar application of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at pre-flowering (S1) and pod formation (S2) stages was most effective in enhancing grain and straw yield, Zn and Fe concentration, and uptake. However, the outcome of this treatment was statistically on par with the results obtained under the treatment ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage. A single spray of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage enhanced the grain and straw yield up to 39.6% and 51.8%, respectively. Similarly, Zn and Fe concentrations showed enhancement in grain (10.9% and 20.4%, respectively) and straw (27.5% and 27.6% respectively) of the lentil. The increase in Zn and Fe uptake by grain was 54.8% and 68.0%, respectively, whereas uptake by straw was 93.6% and 93.7%, respectively. Also the benefit:cost was the highest (1.96) with application of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage. Conclusively, the combined use of ZnSO4·7H2O (0.5%) + FeSO4·7H2O (0.5%) at S1 stage can contribute significantly towards yield, Zn and Fe concentration, as well as uptake and the economic returns of lentil to remediate the Zn and Fe deficiency.


Assuntos
Grão Comestível/efeitos dos fármacos , Compostos Ferrosos/farmacologia , Fertilizantes/análise , Lens (Planta)/efeitos dos fármacos , Micronutrientes/farmacologia , Sulfato de Zinco/farmacologia , Biofortificação , Grão Comestível/metabolismo , Compostos Ferrosos/química , Compostos Ferrosos/metabolismo , Lens (Planta)/metabolismo , Micronutrientes/química , Micronutrientes/metabolismo , Sulfato de Zinco/química , Sulfato de Zinco/metabolismo
10.
ACS Omega ; 6(50): 35030-35038, 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34963984

RESUMO

Stimulus-responsive supramolecular organogels have been broadly studied, but the assembly of a liquid crystalline organogel with a thermoreversible response remains a challenge. This could be attributed to the difficulty of designing organogelators with liquid crystalline properties. Nucleophilic aromatic substitution (SNAr) has been utilized to produce a diversity of pentafluorobenzene-containing aromatics, which are very regioselective to para positions. Those pentafluorobenzene-functionalized aromatics have been ideal compounds for the preparation of calamitic liquid crystals. In this context, novel fluoroterphenyl-containing main-chain polyether (FTP@PE) was synthesized using in situ SNAr polymerization as a convenient and effective synthetic strategy toward the development of fluorescent liquid crystals bearing fluoroterphenyl and ether groups. The fluoroterphenyl unit was synthesized by Cu(I)-supported decarboxylation cross-coupling of potassium pentafluorobenzoate and 1,4-diiodobenzene. The chemical structures of FTP@PE were studied with 1H/13C/19F nuclear magnetic resonance and infrared spectra. The liquid crystal mesophases were determined with differential scanning calorimetry and polarizing optical microscopy. Ultraviolet-visible absorbance and emission spectral profiles showed solvatochromic activity. The nanofibrous morphologies were studied with a scanning electron microscope. The organogels of FTP@PE were developed in a number of solvents via van der Waals attraction forces of aliphatic moieties and π stacking of fluoroterphenyl groups. They demonstrated thermoreversible responsiveness.

11.
Materials (Basel) ; 14(22)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34832170

RESUMO

Melt quenching technique is used for preparing glasses with chemical formula (70P2O5)-(16 - x)CdO-(14ZnO)-(xEr2O3), (x = 1-6 mol%). These glasses were named Er1, Er2, Er3, Er4, Er5, and Er6, respectively. Photon buildup factors, fast neutron absorption, and electron stopping of the prepared glasses were examined. Glasses' density was varied from 3.390 ± 0.003 for the Er1 glass sample to 3.412 ± 0.003 for the Er6 glass sample. The Buildup factor (BUF) spectra have relatively higher values in the Compton Scattering (CS) dominated areas compared to both Photoelectric effect (PE), and Pair Production (PP) dominated energy regions. The highest BUF appeared at the Er atom K-absorption edge, whose intensity increases as the molar concentration of Er2O3 in the glasses increases. The photon absorption efficiency (PAE) of the glasses increases according to the trend (PAE)Er1 < (PAE)Er2 < (PAE)Er3 < (PAE)Er4 < (PAE)Er5 < (PAE)Er6. Fast neutron removal cross-section, FNRC (ΣR) values of the glasses obtained via calculation varied from 0.1045-0.1039 cm-1 for Er1-Er6. Furthermore, the continuous slowing down approximation mode (CSDA) range enhances the kinetic energy of electrons for all glasses. Generally, results revealed that the investigated glasses could be applied for radiation shielding and dosimetric media.

12.
Materials (Basel) ; 14(22)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34832436

RESUMO

Thermal degradation of polymethylmethacrylate (PMMA) was studied by using inorganic salt of aluminum triiodide (AlI3). The composites of PMMA were prepared with AlI3 by changing the concentration of the AlI3 additive from 2% to 10% (w/w). The PMMA composites with AlI3 were characterized by TGA, DTG, SEM, FTIR, HBT, and Py-GC-MS techniques. The FTIR peaks of PMMA composite at 1316, 786, and 693 cm-1 justify the chemical association between PMMA and AlI3. TGA study shows that the stability of PMMA is enhanced by the addition of the AlI3 additive. SEM analysis represented that there is a relationship between polymer and additive when they are mixed at the molecular level. The horizontal burning test (HBT) also confirmed that the AlI3 additive produced the flame retarding properties in PMMA polymer. The burning rate of composite with 10% of AlI3 additive decreases five times as much as compared to pure PMMA polymer. Py-GC-MS analysis deduced that PMMA composite produced less toxic and environment-friendly substances (CO2) by the influence of AlI3 additive as compared to neat PMMA.

13.
Molecules ; 27(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35011443

RESUMO

The ability of microorganisms to reduce inorganic metals has launched an exciting eco-friendly approach towards developing green nanotechnology. Thus, the synthesis of metal nanoparticles through a biological approach is an important aspect of current nanotechnology. In this study, Streptomyces aizuneusis ATCC 14921 gave the small particle of silver nanoparticles (AgNPs) a size of 38.45 nm, with 1.342 optical density. AgNPs produced by Streptomyces aizuneusis were characterized by means of UV-VIS spectroscopy and transmission electron microscopy (TEM). The UV-Vis spectrum of the aqueous solution containing silver ion showed a peak between 410 to 430. Moreover, the majority of nanoparticles were found to be a spherical shape with variables between 11 to 42 nm, as seen under TEM. The purity of extracted AgNPs was investigated by energy dispersive X-ray analysis (EDXA), and the identification of the possible biomolecules responsible for the reduction of Ag+ ions by the cell filtrate was carried out by Fourier Transform Infrared spectrum (FTIR). High antimicrobial activities were observed by AgNPs at a low concentration of 0.01 ppm, however, no deleterious effect of AgNPs was observed on the development and occurrence of Drosophila melanogaster phenotype. The highest reduction in the viability of the human lung carcinoma and normal cells was attained at 0.2 AgNPs ppm.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Nanopartículas Metálicas/química , Prata/química , Streptomyces/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fenômenos Químicos , Relação Dose-Resposta a Droga , Drosophila melanogaster/efeitos dos fármacos , Humanos , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Prata/metabolismo , Análise Espectral
14.
Artigo em Inglês | MEDLINE | ID: mdl-33380257

RESUMO

Reaction of 6-amino-2-methylthio-3-methyluracil with ethyl ethoxymethyleneoxaloacetate or methyl(Z)-2-acetylamino-3-dimethylaminopropenoates afforded diethyl 2-(1,6-dihydro-1-methyl-2-(methylthio)-6-oxopyrimidin-4-yl-amino)methylene malonate or (2E)-methyl 3-(1,6-dihydro-1-methyl-2-(methylthio)-6-oxopyrimidin-4-yl-amino)-2-acetamidoacrylate, respectively. Cyclization of each of the latter products by sodium ethoxide afforded new pyrido [2,3-d]pyrimidines, which were ribosylated with 1-O-acetyl-2,3,5-O-benzoyl-ß-D-ribofuranose by the silylation method yielded the protected nucleosides. The protected nucleosides were debenzoylated by sodium methoxide to afford novel pyrido[2,3-d]pyrimidine nucleosides. The structural assignmentsv for the new compounds were based on their elemental analysis and spectroscopic data.


Assuntos
Nucleotídeos de Pirimidina/química , Nucleotídeos de Pirimidina/síntese química , Técnicas de Química Sintética
15.
Chem Phys Lipids ; 161(1): 32-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19580794

RESUMO

Stable cationic carotenoid aggregates - predominantly of the J-type - develop when the hydrochlorides of carotenoid aldoximes and ketoximes are exposed to water. The oxime hydrochlorides are obtained by simple syntheses from commercially available food color carotenoids. Bluish-purple, unstable transient compounds were observed during hydrochlorination performed at liquid nitrogen temperature.


Assuntos
Carotenoides/química , Oximas/química , Carotenoides/síntese química , Oximas/síntese química , Tensão Superficial , Tensoativos , Água/química
16.
Arch Pharm (Weinheim) ; 341(4): 240-6, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18275038

RESUMO

Several selenolo[2,3-b]quinolines and pyrimido[4',5':4,5]selenolo[2,3-b]quinolines were prepared by annulations via reaction of NaSeH with 2-chloro-3-cyano-4-methylquinoline 1 followed by reactions with aromatic aldehydes, cycloalkanones, and acetic anhydride. Spectroscopic (IR, 1H-NMR, and MS) properties of the synthesized compounds are reported. Some selected compounds 5a, 7b, 7c, 8b-d, 9a, 11b, and 11d were investigated for their anti-inflammatory and analgesic activities; in addition, the most active compounds were tested for their ulcerogenicity and acute toxicity. Moreover, some of the test compounds 7c, 9a, 11b, and 11d were screened for their antibacterial and antifungal activities.


Assuntos
Analgésicos não Narcóticos/farmacologia , Antibacterianos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Antifúngicos/farmacologia , Compostos Organosselênicos/farmacologia , Quinolinas/farmacologia , Analgésicos não Narcóticos/síntese química , Analgésicos não Narcóticos/química , Animais , Antibacterianos/síntese química , Antibacterianos/química , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Antifúngicos/síntese química , Antifúngicos/química , Carragenina , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Dose Letal Mediana , Masculino , Camundongos , Compostos Organosselênicos/síntese química , Compostos Organosselênicos/química , Medição da Dor/efeitos dos fármacos , Quinolinas/síntese química , Quinolinas/química , Ratos , Ratos Wistar , Úlcera Gástrica/induzido quimicamente , Relação Estrutura-Atividade
17.
Chemistry ; 13(16): 4458-66, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17340673

RESUMO

The antioxidant activities-expressed as the electron-donating properties-of five hydrophilic carotenoids (carotenoid surfactants) and three related hydrophobic carotenoids were investigated by flash photolysis. The electron-transfer rates of the carotenoids to the triplet state of the sensitizer 2-nitronaphthalene and the energy transfer rates of triplet 2-nitronaphthalene to the carotenoids were determined. The results demonstrate that the electron-donating effects of the hydrophilic and hydrophobic carotenoids were comparable when evaluated in acetonitrile. In the presence of water, however, electron transfer (i.e., antioxidant efficiency) was enhanced by a factor of four for the hydrophilic carotenoids. The increased hydrophilicity of carotenoids, therefore, could expand their antioxidant properties, thus facilitating their use as aqueous-phase radical scavengers. At the same time, it was shown that supramolecular assembly ("aggregation") of the amphiphilic carotenoids prevented electron transfer, thus deactivating the antioxidant function. Modulation of the biophysical properties of carotenoids through synthetic modification is capable of increasing the biological and medical utility of this natural class of predominantly hydrophobic antioxidant compound.


Assuntos
Antioxidantes/química , Carotenoides/química , Transporte de Elétrons , Transferência de Energia , Interações Hidrofóbicas e Hidrofílicas , Cinética , Estrutura Molecular , Fotoquímica , Fotólise , Fatores de Tempo
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