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1.
Int J Mol Sci ; 23(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36555275

RESUMO

Gastrointestinal diseases, such as peptic ulcers, are caused by a damage in the gastric mucosa provoked by several factors. This stomach injury is regulated by many inflammatory mediators and is commonly treated with proton-pump inhibitors, histamine H2 receptor blockers and antacids. However, various medicinal plants have demonstrated positive effects on gastric ulcer treatment, including plants of the Ceiba genus. The aim of this study was to evaluate the antiulcer and anti-inflammatory activities of the stem bark ethanolic extract of Ceiba speciosa (A. St.-Hil.) Ravenna. We performed a preliminary quantification of phenolic compounds by high-performance liquid chromatography-diode array detection (HPLC-DAD), followed by the prospection of other chemical groups through nuclear magnetic resonance (NMR) spectroscopy. A set of in vitro assays was used to evaluate the extract potential regarding its antioxidant activity (DPPH: 19.83 ± 0.34 µg/mL; TPC: 307.20 ± 6.20 mg GAE/g of extract), effects on cell viability and on the release of TNF-α in whole human blood. Additionally, in vivo assays were performed to evaluate the leukocyte accumulation and total protein quantification in carrageenan-induced air pouch, as well as the antiulcerogenic effect of the extract on an ethanol-induced ulcer in rats. The extract contains flavonoids and phenolic compounds, as well as sugars and quinic acid derivatives exhibiting potent antioxidant activity and low toxicity. The extract reduced the release of TNF-α in human blood and inhibited the activity of p38α (1.66 µg/mL), JAK3 (5.25 µg/mL), and JNK3 (8.34 µg/mL). Moreover, it reduced the leukocyte recruitment on the pouch exudate and the formation of edema, reverting the effects caused by carrageenan. The extract presented a significant prevention of ulcer formation and a higher reduction than the reference drug, Omeprazole. Therefore, C. speciosa extract has demonstrated relevant therapeutic potential for the treatment of gastric diseases, deserving the continuation of further studies to unveil the mechanisms of action of plant bioactive ingredients.


Assuntos
Antiulcerosos , Ceiba , Extratos Vegetais , Úlcera Gástrica , Animais , Humanos , Ratos , Antiulcerosos/farmacologia , Antioxidantes/farmacologia , Carragenina/efeitos adversos , Ceiba/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Fator de Necrose Tumoral alfa/metabolismo , Úlcera
2.
J Chromatogr A ; 1681: 463480, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36095972

RESUMO

In this study, a novel kapok fiber-supported liquid extraction (KF-SLE) method was developed for conveniently extracting analytes from oil samples. Natural kapok fiber without any pretreatment was directly used as an oil support medium. The extraction device was conveniently constructed by directly packing some kapok fibers into a syringe tube. Due to the fibrous property of the kapok fiber, no filter plate was needed. The cost of a KF-SLE device was as low as 0.5 CNY. The KF-SLE process was conveniently conducted using a simple three-step protocol: (1) the oil sample without any pretreatment including dilution was added directedly; (2) then, the oil-immiscible extractant was added; (3) after waiting a certain time for static extraction, the extractant was eluted out by pressing the kapok fibers with the syringe plunger. The extractant could be directly transferred for subsequent instrumental detection. For the feasibility and proof-of-concept study, the method was applied to quantify four synthetic flavor chemicals in edible oils. Satisfied quantification results were obtained with the correlation coefficient (R2) being greater than 0.996, the relative recoveries ranging from 92.90% to 107.53% and intra- and inter-day RSDs being less than 7.56%. All in all, for the first time, the SLE technique was expanded to process oil samples and the method has the characteristics of low cost, environmental friendliness, high sample processing throughput and ease of automation, offering a promising approach for edible oil sample preparations.


Assuntos
Ceiba , Ceiba/química , Estudos de Viabilidade , Óleos/química , Manejo de Espécimes
3.
Molecules ; 27(11)2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35684492

RESUMO

In this work, the extraction procedure of a natural pigment from the flower of Ceiba speciosa (A. St.-Hil.) was optimized by response surface methodology. It is the first time that the extraction of the flower pigment of C. speciosa (FPCS) has been reported, along with an evaluation of its stability and biological activity under various conditions, and an exploration of its potential use as a food additive and in medicine. Specifically, the effects of ethanol concentration, solid-liquid ratio, temperature and time on the extraction rate of FPCS were determined using a Box-Behnken design. The optimum extraction conditions for FPCS were 75% ethanol with a solid-liquid ratio of 1:75 mg/mL) at 66 °C for 39 min. The purification of FPCS using different macroporous resins showed that D101 performed best when the initial mass concentration of the injection solution was 1.50 mg/mL, resulting in a three-fold increase in color value. The yield of dry flowers was 9.75% of fresh petals and the FPCS extraction efficiency was 43.2%. The effects of light, solubility, pH, temperature, sweeteners, edible acids, redox agents, preservatives and metal ions on FPCS were also investigated. Furthermore, the characteristics of FPCS were determined by spectrophotometry at a specific wavelength using the Lambert-Beer law to correlate the mass of FPCS with its absorbance value. An acute toxicological test performed according to Horne's method showed that FPCS is a non-toxic extract and thus may be used as a food additive or in other ingestible forms. Finally, western blotting showed that FPCS prevents lipopolysaccharide-induced hippocampal oxidative stress in mice. The study suggests that FPCS may function as an antioxidant with applications in the food, cosmetics and polymer industries.


Assuntos
Ceiba , Animais , Antioxidantes/farmacologia , Etanol , Flores , Aditivos Alimentares , Camundongos , Extratos Vegetais/farmacologia
4.
Carbohydr Polym ; 278: 118948, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34973765

RESUMO

Creating a low-cost, highly efficient, and recyclable superabsorbent for spilled-oil cleanup is of great significance but remains a big challenge. Herein, we report a facile strategy to produce economic, environmentally friendly, and reusable foam from agricultural waste kapok fibers. These kapok-derived cellulose nanofibrils foams (KNFs) demonstrate a hierarchically porous structure at micro-level with ultra-low density (2.7 mg·cm-3). The superhydrophobic KNFs (150.5°) show outstanding oil absorption (126.8-320.4 g·g-1) and oil-water separation performance. Notably, a facile approach is designed to reuse KNFs easily by a homemade oil release system. The release behavior of the KNFs is quantitatively analyzed and confirmed by the Rigter-Peppas model, indicating that the oil release followed the Fickian diffusion. The KNFs exhibit desirable reusability, and can be recycled for at least 50 times while keeping excellent oil absorption, and release performance. These advantages prove that the KNF is a desirable substitute for spilled-oil treatment.


Assuntos
Ceiba/química , Celulose/química , Nanopartículas/química , Óleos/química , Reciclagem , Fibras de Estresse/química
5.
Environ Sci Pollut Res Int ; 29(34): 51143-51152, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35075565

RESUMO

Non-edible Ceiba oil has the potential to be a sustainable biofuel resource in tropical countries that can replace a portion of today's fossil fuels. Catalytic deoxygenation of the Ceiba oil (high O/C ratio) was conducted to produce hydrocarbon biofuel (high H/C ratio) over NiO-CaO5/SiO2-Al2O3 catalyst with aims of high diesel selectivity and catalyst reusability. In the present study, response surface methodology (RSM) technique with Box-Behnken experimental designs (BBD) was used to evaluate and optimize liquid hydrocarbon yield by considering the following deoxygenation parameters: catalyst loading (1-9 wt. %), reaction temperature (300-380 °C) and reaction time (30-180 min). According to the RSM results, the maximum yield for liquid hydrocarbon n-(C8-C20) was found to be 77% at 340 °C within 105 min and 5 wt. % catalyst loading. In addition, the deoxygenation model showed that the catalyst loading-reaction time interaction has a major impact on the deoxygenation activity. Based on the product analysis, oxygenated species from Ceiba oil were successfully removed in the form of CO2/CO via decarboxylation/decarbonylation (deCOx) pathways. The NiO-CaO5/SiO2-Al2O3 catalyst rendered stable reusability for five consecutive runs with liquid hydrocarbon yield within the range of 66-75% with n-(C15 + C17) selectivity of 64-72%. Despite this, coke deposition was observed after several times of catalyst usage, which is due to the high deoxygenation temperature (> 300 °C) that resulted in unfavourable polymerization side reaction.


Assuntos
Biocombustíveis , Ceiba , Catálise , Hidrocarbonetos , Dióxido de Silício
6.
Molecules ; 26(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917541

RESUMO

This work aimed to evaluate the physical, chemical and antioxidant properties of Ceiba aesculifolia subsp. parvifolia (CAP) tuber and determinate rheological, thermal, physicochemical and morphological properties of the starch extracted. The CAP tuber weight was 3.66 kg; the edible yield was 82.20%. The tuber presented a high hardness value (249 N). The content of carbohydrates (68.27%), crude fiber (15.61%) and ash (9.27%) from the isolated starch, reported in dry weight, were high. Phenolic compounds and flavonoid content of CAP tuber peel were almost 3-fold higher concerning the pulp. CAP tuber starch exhibited a pseudoplastic behavior and low viscosity at concentrations of 5-15%. Purity percentage and color parameters describe the isolated starch as high purity. Thermal characteristics indicated a higher degree of intermolecular association within the granule. Pasting properties describes starch with greater resistance to heat and shear. CAP tuber starch has X-ray diffraction patterns type A. The starch granules were observed as oval and diameters ranging from 5 to 30 µm. CAP tuber could be a good source of fiber and minerals, while its peel could be used for extracting bioactive compounds. Additionally, the starch separated from this tuber could be employed as a thickening agent in food systems requiring a low viscosity and subjected to high temperatures.


Assuntos
Ceiba/química , Tubérculos/química , Reologia , Amido/química , Antioxidantes/análise , Varredura Diferencial de Calorimetria , Cor , Elasticidade , Flavonoides/análise , Polifenóis/análise , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/ultraestrutura , Temperatura , Viscosidade , Difração de Raios X
7.
Molecules ; 25(5)2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32106610

RESUMO

This study aimed to evaluate the chemical composition by gas chromatography-mass spectrometry (GC-MS) and Nuclear Magnetic Resonance (NMR) analyses, the antioxidant activities evaluated by different in vitro assays namely 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), Ferric Reducing Ability Power (FRAP), and ß-carotene bleaching tests, and the inhibitory effects of enzymes linked to obesity (lipase, α-amylase, and α-glucosidase) of fixed seed oil of Ceiba speciosa (A. St.-Hil.). Fourteen compounds were identified. Linoleic acid (28.22%) was the most abundant followed by palmitic acid (19.56%). Malvalic acid (16.15%), sterculic acid (11.11%), and dihydrosterculic acid (2.74%) were also detected. C. speciosa fixed oil exerted a promising ABTS radicals scavenging activity with an IC50 value of 10.21 µg/mL, whereas an IC50 of 77.44 µg/mL against DPPH+ radicals was found. C. speciosa fixed oil inhibited lipase with an IC50 value of 127.57 µg/mL. The present investigation confirmed the functional properties of C. speciosa fixed oil, and proposes its use as valuable source of bioactive constituents.


Assuntos
Ceiba/química , Ácidos Graxos/química , Óleos de Plantas/química , Sementes/química , Antioxidantes/química , Ácidos Graxos/classificação , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química
8.
Nat Prod Res ; 33(23): 3441-3444, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29792358

RESUMO

Several species of the genus Ceiba (Malvaceae) are ethnopharmacologically used. Thus, this study aimed to investigate the in vitro beneficial properties of the aqueous stem bark extract of Ceiba speciosa. The extract presented a great amount of phenolic compounds (117.4 ± 6.2 mg GAE/g). The antioxidant activity was assessed by DPPH (IC50 = 42.87 µg/mL), ORAC (2351.17 µmol TE/g) and FRAP (235.94 µM FeSO4/g) methods. In addition, the extract reduced MCF-7 cell viability as assessed by MTT. However, it prevented mitochondrial membrane depolarization and reduced caspase-9 activity induced by hydrogen peroxide. In conclusion, these findings indicate the extract is an excellent source of natural antioxidants and is able to protect ROS-induced cell death. Therefore, C. speciosa extract may possess beneficial properties for application in pharmaceutical industry as an antioxidant. However, further studies to better elucidate its mechanisms and to isolate its active compounds are required.


Assuntos
Antioxidantes/isolamento & purificação , Ceiba/química , Casca de Planta/química , Antioxidantes/química , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Humanos , Células MCF-7 , Malvaceae/química , Fenóis/análise , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/farmacologia
9.
J Environ Manage ; 219: 340-349, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29753978

RESUMO

This work reports on a series of thermally-bonded, hybrid and oil-sorbent nonwovens developed from binary and tertiary mixing of cotton, kapok, and three varieties of milkweed fibers (Asclepias Syriaca, Calotropis Procera and Calotropis Gigantea) and polypropylene fibers. The physical and chemical properties of the fibers were investigated to examine their oleophilic character. It was observed that all the fiber surfaces were covered with natural wax. Further, kapok and milkweed fibers were found to have less cell wall thickness and high void ratio. Oil sorption and retention characteristics of these fibers were studied in loose fibrous form as well as in structured assembly form (thermally-bonded nonwovens) using high density oil and diesel oil. The effects of fiber diameter, fiber cross-sectional shape, fiber surface area and porosity on the oil sorption behavior were discussed. An excellent and a selective oil sorption behavior of milkweed fibers (Calotropis Procera and Calotropis Gigantea) blended with cotton and polypropylene fibers were observed. The maximum oil sorption capacity of the developed thermal bonded nonwoven was 40.16 g/g for high density (HD) oil and 23.00 g/g for diesel oil. Further, a high porosity combined with high surface area played a major role in deciding the oil sorption and retention characteristics.


Assuntos
Óleos , Plantas , Polipropilenos , Ceiba , Estudos Transversais , Têxteis
10.
Environ Technol ; 39(9): 1089-1095, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28463052

RESUMO

Butyl methacrylate (BMA) was grafted onto kapok fiber using benzoyl peroxide (BPO) as initiator. The structure of the grafted kapok was investigated using Fourier transform infrared spectroscopy and scanning electron microscopy. The results illustrated that BMA was successfully grafted onto the kapok fiber surface. The effects of monomer concentration, temperature and time on the oil absorbency of grafted kapok fiber were investigated. The oil absorbencies of raw kapok, NaClO2-treated kapok fiber and kapok-g-butyl methacrylate were evaluated and compared. Compared with raw kapok fiber, grafted kapok fiber showed the highest oil absorbency, with the increase percentage of 63.4%, 42.5% and 56.4% for chloroform, toluene and n-hexane, respectively. Furthermore, the as-developed grafted kapok fiber exhibited excellent reusability, and can be utilized as an eco-friendly material for recovering oil released into the surroundings.


Assuntos
Ceiba/química , Metacrilatos/química , Adsorção , Óleos , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Int J Syst Evol Microbiol ; 67(5): 1158-1162, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28073396

RESUMO

Strain XMU 110T, isolated from the rhizosphere soil of a flowering tree, Ceiba speciosa, was characterized by polyphasic taxonomy. Phylogenetic analysis based on 16S rRNA gene comparisons revealed that strain XMU 110T showed the highest similarity of 97.9 % to Nonomuraea jabiensis DSM 45507T, and indicated the closest relatives were Nonomuraearoseoviolaceasubsp.roseoviolacea ATCC 27297T (97.8 % 16S rRNA gene sequence similarity) and Nonomuraea salmonea DSM 43678T (97.4 %) after a neighbour-joining analysis. The phenotypic characteristics, as well as the DNA-DNA relatedness values between strain XMU 110T and N. roseoviolaceasubsp. roseoviolacea ATCC 27297T (48.07±1.99 %) and N. salmonea DSM 43678T (40.55±8.30 %), distinguished the novel strain from its closest phylogenetic neighbours. The morphological, physiological and chemotaxonomic characteristics such as phospholipid type, diagnostic diamino acid of the peptidoglycan, whole-cell sugars, major menaquinones and major fatty acids further supported the assignment of strain XMU 110T to the genus Nonomuraea. The G+C content of the genomic DNA was 66.2 mol%. Based on the taxonomic data, strain XMU 110Trepresents a novel species of the genus Nonomuraea, for which the name Nonomuraea ceibae sp. nov. is proposed. The type strain is XMU 110T (=MCCC 1K03213T= KCTC 39826T).


Assuntos
Actinomycetales/classificação , Ceiba/microbiologia , Filogenia , Rizosfera , Microbiologia do Solo , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
Anim Sci J ; 88(8): 1066-1074, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27891709

RESUMO

Kapok seed and oil from the tropical zone are widely used as pig feed to harden porcine fat in Japan. This study evaluated the effect of dietary kapok oil supplementation on pork quality and sensory traits. Five Duroc pigs each were assigned to an experimental group supplemented with kapok oil and a control group. Dietary kapok oil supplementation had no effect on growth performance and intramuscular fat content in the Longissimus dorsi muscle (LM). Supplemental kapok oil increased saturated fatty acid contents in subcutaneous and intramuscular fat and decreased monounsaturated fatty acid levels (P < 0.05). Off-flavor detection by a trained panel was higher in the experimental than the control group (P < 0.05), but tenderness, juiciness, texture and flavor intensity of LM chops were similar in both groups. The overall palatability of pork as judged by a consumer panel decreased with kapok oil supplementation (P < 0.01). These results indicate that while growth performance, intramuscular fat contents and carcass characteristics were unchanged, while dietary kapok oil supplementation makes firm fat to prevent inferior soft fat in pork, it can lower the palatability of pork due to a decrease in monounsaturated fatty acids.


Assuntos
Ceiba , Dieta/veterinária , Suplementos Nutricionais , Qualidade dos Alimentos , Carne , Óleos de Plantas/administração & dosagem , Suínos/crescimento & desenvolvimento , Suínos/metabolismo , Paladar , Adulto , Ração Animal/análise , Animais , Ácidos Graxos/metabolismo , Ácidos Graxos Monoinsaturados/metabolismo , Feminino , Humanos , Lipídeos/análise , Masculino , Carne/análise , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Adulto Jovem
13.
Bioresour Technol ; 211: 248-56, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27019128

RESUMO

Recently, a great attention has been paid to advanced microwave technology that can be used to markedly enhance the biodiesel production process. Ceiba pentandra Seed Oil containing high free fatty acids (FFA) was utilized as a non-edible feedstock for biodiesel production. Microwave-assisted esterification pretreatment was conducted to reduce the FFA content for promoting a high-quality product in the next step. At optimum condition, the conversion was achieved 94.43% using 2wt% of sulfuric acid as catalyst where as 20.83% conversion was attained without catalyst. The kinetics of this esterification reaction was also studied to determine the influence of factors on the rate of reaction and reaction mechanisms. The results indicated that microwave-assisted esterification was of endothermic second-order reaction with the activation energy of 53.717kJ/mol.


Assuntos
Ceiba/química , Ácidos Graxos não Esterificados , Micro-Ondas , Óleos de Plantas/química , Sementes/química , Biocombustíveis , Esterificação , Ácidos Graxos não Esterificados/química , Ácidos Graxos não Esterificados/metabolismo , Cinética
14.
Water Environ Res ; 86(4): 360-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24851332

RESUMO

In this paper, an oil sorbent based on superhydrophobic kapok fiber fabricated by the sol-gel method was used for the selective sorption of oil from the surface of artificial seawater. The effects of process parameters such as seawater pH, seawater temperature, and contact time on the extent of oil sorption were investigated. The as-prepared fiber showed higher oil sorption capacity than raw fiber in both the trenchant acid and alkaline seawater environment. Results of the kinetic studies show that the sorption process follows pseudo-second-order reaction kinetics. The thermodynamic investigations demonstrate that the sorption process is spontaneous and endothermic. In addition, the as-prepared fiber can float on the water surface after the sorption of oil, which facilitates the post-processing of oil-loaded fiber. The modified fiber might provide a simple method for the removal and collection of oil on the water surface.


Assuntos
Ceiba/química , Recuperação e Remediação Ambiental/métodos , Água do Mar/química , Poluentes Químicos da Água/química , Poluição Química da Água/prevenção & controle , Absorção , Interações Hidrofóbicas e Hidrofílicas , Cinética , Termodinâmica
15.
J Environ Sci (China) ; 25(2): 246-53, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23596942

RESUMO

Kapok fibers have been acetylated for oil spill cleanup in the aqueous environment. The structures of raw and acetylated kapok fiber were characterized using Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). Without severe damage to the lumen structures, the kapok fibers were successfully acetylated and the resulting fibers exhibited a better oil sorption capacity than raw fibers for diesel and soybean oil. Compared with high viscosity soybean oil, low viscosity diesel shows a better affinity to the surface of acetylated fibers. Sorption kinetics is fitted well by the pseudo second-order model, and the equilibrium data can be described by the Freundlich isotherm model. The results implied that acetylated kapok fiber can be used as the substitute for non-biodegradable oil sorption materials.


Assuntos
Ceiba/química , Óleos/química , Acetilação , Adsorção , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química
16.
Mar Pollut Bull ; 69(1-2): 91-6, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23419751

RESUMO

Based on raw kapok fiber, two kinds of oil absorbers with high sorption capacity were prepared by a facile solution-immersion process. The coated polymer with low surface energy and rough fiber surface play important role in the retention of oil. The as-prepared fiber can quickly absorb gasoline, diesel, soybean oil, and paraffin oil up to above 74.5%, 66.8%, 64.4% and 47.8% of oil sorption capacity of raw fiber, respectively. The absorbed oils can be easily recovered by a simple vacuum filtration and the recovered coated-fiber still can be used for several cycles without obvious loss in oil sorption capacity. The thermodynamic study indicates that the adsorption process is spontaneous and exothermic, with complex physisorption and chemisorption. The results suggest that the coated fiber can be used as a low-cost alternative for the removal of oil spilled on water surface.


Assuntos
Ceiba , Recuperação e Remediação Ambiental/métodos , Óleos/análise , Parafina/análise , Poluição por Petróleo , Petróleo/análise , Óleo de Soja/análise , Poluentes Químicos da Água/análise , Absorção
17.
Environ Technol ; 34(21-24): 3169-75, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24617076

RESUMO

More research and development on novel oil sorbent materials is needed to protect the environmental pollution. New nonwoven fabrics (pads) of polypropylene (PP)/kapok blends (blend ratio: 100/0, 75/25, 50/50, 25/75 and 10/90) were prepared by needle punching process at a fixed (optimized) condition (punch density: 50 punches/cm2 and depth: 4mm). This study focused on the effect of blend ratio of PP/kapok nonwoven fabrics on oil sorption capacities to find the best blend ratio having the highest synergy effect. The PP/kapok blend (50/50) sample has the lowest bulk density and showed the best oil absorption capacity. The oil sorption capacity of PP/kapok blend (50/50) nonwoven fabric for kerosene/soybean oil [21.09/27.01 (g oil/g sorbent)] was 1.5-2 times higher than those of commercial PP pad oil sorbents. The highest synergy effect of PP/kapok blend (50/50) was ascribed to the lowest bulk density of PP/kapok blend (50/50), which might be due to the highest morphologically incompatibility between PP fibre and kapok. These results suggest that the PP/kapok blend (50/50) having the highest synergy effect has a high potential as a new high-performance oil sorbent material.


Assuntos
Ceiba/química , Fibra de Algodão , Óleos/química , Óleos/isolamento & purificação , Polipropilenos/química , Têxteis/análise , Ultrafiltração/métodos , Adsorção , Misturas Complexas/química , Teste de Materiais , Ultrafiltração/instrumentação
18.
Environ Technol ; 33(4-6): 481-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22629620

RESUMO

The characteristics and water/oil sorption effectiveness ofkapok fibre, sugarcane bagasse and rice husks have been compared. The three biomass types were subjected to field emission scanning electron microscopy-energy dispersive X-ray spectroscopy and surface tension analyses for liquid-air and oil-water systems were conducted. Both kapok fibre and sugarcane bagasse exhibit excellent oil sorption capabilities for diesel, crude, new engine and used engine oils as their oil sorption capacities all exceed 10 g/g. The synthetic sorbent exhibits oil sorption capacities comparable with sugarcane bagasse, while rice husks exhibit the lowest oil sorption capacities among all the sorbents. Kapok fibre shows overwhelmingly high oil-to-water sorption (O/W) ratios ranging from 19.35 to 201.53 while sugarcane bagasse, rice husks and synthetic sorbent have significantly lower O/W ratios (0.76-2.69). This suggests that kapok fibre is a highly effective oil sorbent even in well-mixed oil-water media. An oil sorbent suitability matrix is proposed to aid stakeholders in evaluating customized oil removal usage of the natural sorbents.


Assuntos
Ceiba/química , Oryza/química , Poluição por Petróleo/prevenção & controle , Componentes Aéreos da Planta/química , Saccharum/química , Ultrafiltração/métodos , Poluentes Químicos da Água/isolamento & purificação , Absorção , Óleos Combustíveis , Purificação da Água/métodos
19.
J Hazard Mater ; 186(1): 526-32, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21146290

RESUMO

This article reports on oil sorption behavior of fiber assemblies made up of single natural and synthetic fibers as well as blend of natural and synthetic fibers when tested with high density oil and diesel oil. A series of filled fiber assemblies were prepared from 100% polypropylene, kapok, and milkweed fibers and another series of bonded structured fiber assemblies were prepared from a 70/30 blend of kapok and polypropylene fibers and a 70/30 blend of milkweed and polypropylene fibers. It was observed that the porosity of the fiber assemblies played a very important role in determining its oil sorption capacity. The polypropylene fiber assembly exhibited the highest sorption capacity (g/g) followed by the kapok and milkweed fiber assemblies at porosity <0.98. At higher porosities (above 0.98), polypropylene filled fiber assembly has poor sorption capacity due to large sized inter fiber pore. The kapok and milkweed fibers have intra fiber porosities of 0.81 and 0.83, respectively. All the fiber assemblies showed higher oil sorption capacity with the high density oil as compared to the diesel oil. As the kapok and milkweed fiber have low cellulose content, hence their slow degradation is an advantage in fresh and marine water applications. The good sorption capacity of kapok and milkweed fiber assemblies along with their bio-degradable nature offer great scope for structuring them into fiber assemblies with large porosity and uniform pores to have efficient oil sorbents.


Assuntos
Asclepias/química , Ceiba/química , Óleos/química , Polipropilenos/química , Microscopia Eletrônica de Varredura
20.
Asian Pac J Allergy Immunol ; 28(2-3): 155-61, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21038785

RESUMO

BACKGROUND: Different mattress materials may affect the accumulation of allergens. OBJECTIVE: To compare the amount of group 1 dust mite allergens (Der p1 + Der f1) on mattresses made of different kinds of materials before and after use. METHODS: Sixty new mattresses made of kapok, synthetic fiber, coconut fiber and sponge-like polyurethane, were placed in the house officers' dormitory at Siriraj hospital, Thailand. The dust samples were collected before (0), 1, 2, 3, 6, 9 and 12 months after the mattresses were used. Group 1 dust mite allergens were analyzed using two-site monoclonal antibody ELISA. RESULTS: Der f1 made up 86.7 % of group 1 allergens found in the matress dust. After the 2nd month, only the mean level in sponge-like polyurethane mattress was under 2 microg/g dust (sensitized level). At the 6th month, the mean levels were 13.1 in coconut, 21.7 in kapok and 17.3 microg/g dust in synthetic fiber, all of which were more than 10 microg/g dust (symptomatic level). At the 9th month, the level in sponge-like polyurethane mattress was increased to 11.2 microg/g. At 12th month the level in coconut fiber, sponge-like polyurethane synthetic fiber and kapok mattresses were 20.2, 22.4, 28.9 and 32.2 microg/g dust respectively. CONCLUSIONS: The accumulation rate in kapok and synthetic mattresses was significantly higher than coconut and sponge-like polyurethane mattresses. The mean level of group 1 mite allergens exceeded 10 microg/g dust after the 6th month of use in coconut fiber, kapok and synthetic fiber and at the 9th month in sponge-like polyurethane mattress.


Assuntos
Antígenos de Dermatophagoides/metabolismo , Asma/epidemiologia , Manufaturas/estatística & dados numéricos , Têxteis/estatística & dados numéricos , Animais , Antígenos de Dermatophagoides/imunologia , Proteínas de Artrópodes , Asma/imunologia , Leitos , Ceiba/imunologia , Cocos/imunologia , Cisteína Endopeptidases , Poeira/análise , Hospitais , Humanos , Poliuretanos , Pyroglyphidae/imunologia , Tailândia
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